diff --git a/.github/workflows-in/Makefile b/.github/workflows-in/Makefile
index 6cfc1911c..ab6208641 100644
--- a/.github/workflows-in/Makefile
+++ b/.github/workflows-in/Makefile
@@ -1,35 +1,36 @@
-SHELL := bash
+M := .cache/makes
+$(shell [ -d $M ] || git clone -q https://github.com/makeplus/makes $M)
+include $M/init.mk
+YS-VERSION := 0.2.8
+include $M/ys.mk
+include $M/clean.mk
+include $M/shell.mk
 
-YS_VERSION := 0.2.4
-YS_PREFIX := $(shell cd ../.. ; pwd)/build/ys
-YS := $(YS_PREFIX)/bin/ys-$(YS_VERSION)
+INPUT-FILES := $(wildcard */*)
+SOURCE-FILES := $(wildcard *.ys)
+TARGET-FILES := $(SOURCE-FILES:%.ys=../workflows/%.yml)
 
-INPUT_FILES := $(wildcard */*)
-SOURCE_FILES := $(wildcard *.ys)
-TARGET_FILES := $(SOURCE_FILES:%.ys=../workflows/%.yml)
+export YSPATH := $(ROOT)/ys
 
-export PATH := $(YS_PREFIX)/bin:$(PATH)
-export YSPATH := $(shell pwd -P)/ys
 
-
-build: $(TARGET_FILES)
+build: $(TARGET-FILES)
 
 
 test: force build
-	@git diff --exit-code $(TARGET_FILES) && \
+	@git diff --exit-code $(TARGET-FILES) && \
 	  echo -e '\nPASS - No normative changes to .github/workflows/*.yml'
 
 
-DIFF_ORIG_COMMIT ?= HEAD
+DIFF-ORIG-COMMIT ?= HEAD
 diff:
-	@for s in $(SOURCE_FILES); do \
+	@for s in $(SOURCE-FILES); do \
 	  s=$${s##*/}; \
 	  t=../workflows/$${s%.yml}; \
-	  [[ $$(git show $(DIFF_ORIG_COMMIT):.github/workflows/.$$t \
+	  [[ $$(git show $(DIFF-ORIG-COMMIT):.github/workflows/.$$t \
 	          2>/dev/null) ]] && t=.$$t; \
 	  diff -u --color=auto \
 	    <(yq -P 'sort_keys(..)' \
-	         -o=props <(git show $(DIFF_ORIG_COMMIT):.github/workflows/$$t) | \
+	         -o=props <(git show $(DIFF-ORIG-COMMIT):.github/workflows/$$t) | \
 		 grep -Ev '(^$$|^#)' \
 	     ) \
 	    <(yq -P 'sort_keys(..)' \
@@ -43,8 +44,8 @@ force:
 	touch *.ys
 
 
-../workflows/%.yml: %.ys $(YS) $(INPUT_FILES)
-	@if [ -f "$@" ] ; then chmod a+w $@ ; fi
+../workflows/%.yml: %.ys $(YS) $(INPUT-FILES)
+	@if [[ -f $@ ]] ; then chmod a+w $@ ; fi
 	@echo "# DO NOT EDIT - GENERATED FROM .github/workflows-in/$<" > $@
 	@echo >> $@
 	$(YS) -Y $< >> $@
@@ -55,11 +56,8 @@ force:
 # Auto install a specific version of ys
 install-ys: $(YS)
 $(YS):
-	mkdir -p $(YS_PREFIX)
-	curl -s https://yamlscript.org/install | \
-	  BIN=1 VERSION=$(YS_VERSION) PREFIX=$(YS_PREFIX) bash
 
 
 stats:
 	@echo "ys : $$(wc -lm *.ys)"
-	@echo "yml: $$(wc -lm *.yml)"
+	@echo "yml: $$(wc -lm ../workflows/*.yml)"
diff --git a/.github/workflows-in/api.ys b/.github/workflows-in/api.ys
index 4186efc42..fdda88d7d 100644
--- a/.github/workflows-in/api.ys
+++ b/.github/workflows-in/api.ys
@@ -1,4 +1,4 @@
-!yamlscript/v0
+!ys-0
 
 python-preamble-job =::
   runs-on: ${{matrix.config.os}}
@@ -85,10 +85,9 @@ python-bare-tests =::
       python -m pytest -vvv api/python/tests
 
 
----
-!yamlscript/v0:
+--- !ys:
 
-:use common: :all
+:use common:
 :: workflow-setup()
 
 jobs:
@@ -101,9 +100,9 @@ jobs:
     name: pybare/${{matrix.config.pythonv}}/${{matrix.config.os}}
     :: python-preamble-job
     steps:
-    - :: checkout-action
-    - :: python-preamble-steps
-    - :: python-bare-tests
+      - :: checkout-action
+      - :: python-preamble-steps
+      - :: python-bare-tests
 
   #----------------------------------------------------
   # run tests with built+installed wheels
@@ -114,9 +113,9 @@ jobs:
     env:
        CMAKE_FLAGS: -DCMAKE_BUILD_TYPE=Release -DCMAKE_VERBOSE_MAKEFILES=ON
     steps:
-    - :: checkout-action
-    - :: python-preamble-steps
-    - :: python-wheel-tests
+      - :: checkout-action
+      - :: python-preamble-steps
+      - :: python-wheel-tests
   pywheelwin:
     :: setup-job('api' 'pywheel_win')
     name: pywheel/${{matrix.config.pythonv}}/${{matrix.config.os}}
@@ -124,7 +123,7 @@ jobs:
     env:
        CMAKE_FLAGS: -DCMAKE_BUILD_TYPE=Release -DCMAKE_VERBOSE_MAKEFILES=ON
     steps:
-    - :: checkout-action
-    - :: python-preamble-steps
-    - :: setup-env-win
-    - :: python-wheel-tests
+      - :: checkout-action
+      - :: python-preamble-steps
+      - :: setup-env-win
+      - :: python-wheel-tests
diff --git a/.github/workflows-in/benchmarks.ys b/.github/workflows-in/benchmarks.ys
index 7a589a221..e01474629 100644
--- a/.github/workflows-in/benchmarks.ys
+++ b/.github/workflows-in/benchmarks.ys
@@ -1,6 +1,6 @@
-!yamlscript/v0:
+!ys-0:
 
-:use common: :all
+:use common:
 :: workflow-setup()
 
 jobs:
@@ -24,7 +24,7 @@ jobs:
         #- {std: 17, comp: vs2019 , os: windows-2019, cmkflags: -G 'Visual Studio 16 2019' -A x64}
         - {std: 17, comp: vs2022 , os: windows-2022, cmkflags: -G 'Visual Studio 17 2022' -A x64}
         - {std: 17, comp: xcode15, os: macos-15-intel, xcver: 16, cmkflags: -G Xcode -DCMAKE_OSX_ARCHITECTURES=x86_64}
-    env:: -{'BM' 'ON'} + load('share/env.yaml')
+    env:: +{'BM' 'ON'} + load('share/env.yaml')
     steps:
     - :: checkout-action
     - :: version-get-vars
diff --git a/.github/workflows-in/clang.ys b/.github/workflows-in/clang.ys
index c7272c05c..a50dc2543 100644
--- a/.github/workflows-in/clang.ys
+++ b/.github/workflows-in/clang.ys
@@ -1,6 +1,6 @@
-!yamlscript/v0:
+!ys-0:
 
-:use common: :all
+:use common:
 :: workflow-setup()
 
 jobs:
@@ -13,7 +13,7 @@ jobs:
       fail-fast: false
       matrix:
         item =: \({:std %1, :cxx %2, :bt %3, :bitlinks 'shared64 static32'})
-        include:: &include1 -[
+        include:: &include1 +[
           item(20 'clang++-18' 'Debug'  )
           item(20 'clang++-18' 'Release') ]
     env:: load('share/env.yaml')
@@ -43,7 +43,7 @@ jobs:
       fail-fast: false
       matrix:
         include: *include1
-    env:: -{'CXXFLAGS' '-fno-exceptions -fno-rtti'} +
+    env:: +{'CXXFLAGS' '-fno-exceptions -fno-rtti'} +
           load('share/env.yaml')
     steps:: checkout-action-docker + install-cxx + run-steps
 
@@ -107,6 +107,7 @@ jobs:
       - :: run-clang-manual-with-flags('Release' '-O3 -DNDEBUG -m${{matrix.bits}}')
       - :: run-clang-manual-with-flags('Release' '-Os -DNDEBUG -m${{matrix.bits}}')
 
+
   #----------------------------------------------------------------------------
   clangsan:
     :: setup-job('clang' 'clangsan')
diff --git a/.github/workflows-in/clang_tidy.ys b/.github/workflows-in/clang_tidy.ys
index 54733cfa9..c8c9667a0 100644
--- a/.github/workflows-in/clang_tidy.ys
+++ b/.github/workflows-in/clang_tidy.ys
@@ -1,6 +1,6 @@
-!yamlscript/v0:
+!ys-0:
 
-:use common: :all
+:use common:
 :: workflow-setup()
 
 jobs:
diff --git a/.github/workflows-in/coverage.ys b/.github/workflows-in/coverage.ys
index 7864b8a26..8a15d5486 100644
--- a/.github/workflows-in/coverage.ys
+++ b/.github/workflows-in/coverage.ys
@@ -1,6 +1,6 @@
-!yamlscript/v0:
+!ys-0:
 
-:use common: :all
+:use common:
 :: workflow-setup()
 
 jobs:
diff --git a/.github/workflows-in/embedded.ys b/.github/workflows-in/embedded.ys
index 88f703746..f7a4f484a 100644
--- a/.github/workflows-in/embedded.ys
+++ b/.github/workflows-in/embedded.ys
@@ -1,9 +1,8 @@
-!yamlscript/v0:
+!ys-0:
 
 # DOCKER DEBUGGING EXAMPLES AT THE END!
 
-
-:use common: :all
+:use common:
 :: workflow-setup()
 
 ::
@@ -100,7 +99,6 @@ matrix-items =::
 
 
 jobs:
-
   canary11:
     :: setup-job('embedded' 'canary11')
     :: define-job(list(first(matrix-items)) steps11 'c++11')
diff --git a/.github/workflows-in/emscripten.ys b/.github/workflows-in/emscripten.ys
index e57784a9a..a7be7da89 100644
--- a/.github/workflows-in/emscripten.ys
+++ b/.github/workflows-in/emscripten.ys
@@ -1,6 +1,6 @@
-!yamlscript/v0:
+!ys-0:
 
-:use common: :all
+:use common:
 :: workflow-setup()
 
 jobs:
@@ -18,14 +18,14 @@ jobs:
         item =: \({:std %1, :cxx 'em++', :emver %2, :bt %3,
                    :os 'ubuntu-latest', :bitlinks :static32})
         include:
-       #- ! item(11 '2.0.34' 'Debug')
-        - ! item(11 '2.0.34' 'Release')
-       #- ! item(20 '2.0.34' 'Debug')
-        - ! item(20 '2.0.34' 'Release')
-       #- ! item(11 '3.0.0' 'Debug')
-        - ! item(11 '3.0.0' 'Release')
-       #- ! item(20 '3.0.0' 'Debug')
-        - ! item(20 '3.0.0' 'Release')
+        #- ! item(11 '2.0.34' 'Debug')
+         - ! item(11 '2.0.34' 'Release')
+        #- ! item(20 '2.0.34' 'Debug')
+         - ! item(20 '2.0.34' 'Release')
+        #- ! item(11 '3.0.0' 'Debug')
+         - ! item(11 '3.0.0' 'Release')
+        #- ! item(20 '3.0.0' 'Debug')
+         - ! item(20 '3.0.0' 'Release')
     env:: load('share/env.yaml') + {'EMSCRIPTEN_CACHE_FOLDER' 'emsdk-cache'}
          + {'CMAKE_FLAGS' '-DRYML_TEST_SUITE=OFF'}
     steps:
diff --git a/.github/workflows-in/gcc.ys b/.github/workflows-in/gcc.ys
index d43b2afaa..bec05b19c 100644
--- a/.github/workflows-in/gcc.ys
+++ b/.github/workflows-in/gcc.ys
@@ -1,6 +1,6 @@
-!yamlscript/v0:
+!ys-0:
 
-:use common: :all
+:use common:
 :: workflow-setup()
 
 jobs:
@@ -16,14 +16,14 @@ jobs:
         item =: \({:std %1, :cxx "g++-$a(%2)", :bt %3, :bitlinks 'shared64 static32', :img "$a(%4)"})
         include: &include1
         # use gcc13 because it's a lot faster than gcc14
-        - ! item(11  13 'Debug'   '22.04')
-        - ! item(11  13 'Release' '22.04')
-        - ! item(20  13 'Debug'   '22.04')
-        - ! item(20  13 'Release' '22.04')
-        - ! item(11   5 'Debug'   '18.04')
-        - ! item(11   5 'Release' '18.04')
-        - ! item(11 4.8 'Debug'   '18.04')
-        - ! item(11 4.8 'Release' '18.04')
+        - :: item(11  13 'Debug'   '22.04')
+        - :: item(11  13 'Release' '22.04')
+        - :: item(20  13 'Debug'   '22.04')
+        - :: item(20  13 'Release' '22.04')
+        - :: item(11   5 'Debug'   '18.04')
+        - :: item(11   5 'Release' '18.04')
+        - :: item(11 4.8 'Debug'   '18.04')
+        - :: item(11 4.8 'Release' '18.04')
     env:: load('share/env.yaml')
     steps:: checkout-manual + install-cxx + run-steps
 
@@ -187,10 +187,8 @@ jobs:
       fail-fast: false
       matrix:
         include::
-          ? for
-              san qw(asan lsan tsan ubsan)
-              std [11 14 17 20]
-          : ! { std:: std, cxx: g++-14, bt:: san, bitlinks: static64 }
+          for san qw(asan lsan tsan ubsan), std [11 14 17 20]::
+            { std:: std, cxx: g++-14, bt:: san, bitlinks: static64 }
     env:: load('share/env.yaml')
     steps:: checkout-action-docker + install-cxx + run-steps
 
@@ -208,13 +206,13 @@ jobs:
         include:
         # these jobs take much longer, so run only one bitlink pair per job to
         # profit from parallelism
-        - ! item(11 'Debug')
-        - ! item(11 'Release')
-        - ! item(14 'Debug')
-        - ! item(14 'Release')
-        - ! item(17 'Debug')
-        - ! item(17 'Release')
-    env:: -{'TOOLCHAIN' '${{matrix.toolchain}}'} + load('share/env.yaml')
+        - :: item(11 'Debug')
+        - :: item(11 'Release')
+        - :: item(14 'Debug')
+        - :: item(14 'Release')
+        - :: item(17 'Debug')
+        - :: item(17 'Release')
+    env:: +{'TOOLCHAIN' '${{matrix.toolchain}}'} + load('share/env.yaml')
     steps:
     - :: checkout-manual
     - name: install gcc-arm-linux-gnueabihf
diff --git a/.github/workflows-in/infra.ys b/.github/workflows-in/infra.ys
index a5917f9c8..e46497479 100644
--- a/.github/workflows-in/infra.ys
+++ b/.github/workflows-in/infra.ys
@@ -1,6 +1,6 @@
-!yamlscript/v0:
+!ys-0:
 
-:use common: :all
+:use common:
 :: workflow-setup()
 
 jobs:
diff --git a/.github/workflows-in/install.ys b/.github/workflows-in/install.ys
index ec76ff605..ee29bdf02 100644
--- a/.github/workflows-in/install.ys
+++ b/.github/workflows-in/install.ys
@@ -1,8 +1,7 @@
-!yamlscript/v0:
+!ys-0:
 
-:use common: :all
-::
-  workflow-setup:: test_install
+:use common:
+:: workflow-setup('test_install')
 
 env:
   PROJ_PFX_TARGET: ryml-
diff --git a/.github/workflows-in/macosx.ys b/.github/workflows-in/macosx.ys
index a8e14f58f..699d2954f 100644
--- a/.github/workflows-in/macosx.ys
+++ b/.github/workflows-in/macosx.ys
@@ -1,6 +1,6 @@
-!yamlscript/v0:
+!ys-0:
 
-:use common: :all
+:use common:
 :: workflow-setup()
 
 jobs:
diff --git a/.github/workflows-in/release.ys b/.github/workflows-in/release.ys
index 39226ca37..95a724512 100644
--- a/.github/workflows-in/release.ys
+++ b/.github/workflows-in/release.ys
@@ -1,5 +1,6 @@
-!yamlscript/v0
+!ys-0
 
+use common:
 
 defn pywhl(pyv cibwpyv cibwarch cibwplatform os vsenvarch='' cmkflags='')::  # NOTE: cannot use _ in names?
     name:: "python/$pyv/$cibwplatform"
@@ -15,87 +16,87 @@ defn pywhl(pyv cibwpyv cibwarch cibwplatform os vsenvarch='' cmkflags='')::  # N
 
 python-wheel-matrix =::
 #          pyv        arch         platform            os
-- ! pywhl('3.13' 313 'x86_64'     'manylinux_x86_64'  'ubuntu-24.04')
-- ! pywhl('3.13' 313 'i686'       'manylinux_i686'    'ubuntu-24.04')
-- ! pywhl('3.13' 313 'aarch64'    'manylinux_aarch64' 'ubuntu-24.04-arm')
-- ! pywhl('3.13' 313 'x86_64'     'macosx_x86_64'     'macos-15-intel')
-- ! pywhl('3.13' 313 'arm64'      'macosx_arm64'      'macos-latest')
-- ! pywhl('3.13' 313 'universal2' 'macosx_universal2' 'macos-latest')
+- :: pywhl('3.13' 313 'x86_64'     'manylinux_x86_64'  'ubuntu-24.04')
+- :: pywhl('3.13' 313 'i686'       'manylinux_i686'    'ubuntu-24.04')
+- :: pywhl('3.13' 313 'aarch64'    'manylinux_aarch64' 'ubuntu-24.04-arm')
+- :: pywhl('3.13' 313 'x86_64'     'macosx_x86_64'     'macos-15-intel')
+- :: pywhl('3.13' 313 'arm64'      'macosx_arm64'      'macos-latest')
+- :: pywhl('3.13' 313 'universal2' 'macosx_universal2' 'macos-latest')
 #          pyv        arch         platform            os
-- ! pywhl('3.12' 312 'x86_64'     'manylinux_x86_64'  'ubuntu-24.04')
-- ! pywhl('3.12' 312 'i686'       'manylinux_i686'    'ubuntu-24.04')
-- ! pywhl('3.12' 312 'aarch64'    'manylinux_aarch64' 'ubuntu-24.04-arm')
-- ! pywhl('3.12' 312 'x86_64'     'macosx_x86_64'     'macos-15-intel')
-- ! pywhl('3.12' 312 'arm64'      'macosx_arm64'      'macos-latest')
-- ! pywhl('3.12' 312 'universal2' 'macosx_universal2' 'macos-latest')
+- :: pywhl('3.12' 312 'x86_64'     'manylinux_x86_64'  'ubuntu-24.04')
+- :: pywhl('3.12' 312 'i686'       'manylinux_i686'    'ubuntu-24.04')
+- :: pywhl('3.12' 312 'aarch64'    'manylinux_aarch64' 'ubuntu-24.04-arm')
+- :: pywhl('3.12' 312 'x86_64'     'macosx_x86_64'     'macos-15-intel')
+- :: pywhl('3.12' 312 'arm64'      'macosx_arm64'      'macos-latest')
+- :: pywhl('3.12' 312 'universal2' 'macosx_universal2' 'macos-latest')
 #          pyv        arch         platform            os
-- ! pywhl('3.11' 311 'x86_64'     'manylinux_x86_64'  'ubuntu-24.04')
-- ! pywhl('3.11' 311 'i686'       'manylinux_i686'    'ubuntu-24.04')
-- ! pywhl('3.11' 311 'aarch64'    'manylinux_aarch64' 'ubuntu-24.04-arm')
-- ! pywhl('3.11' 311 'x86_64'     'macosx_x86_64'     'macos-15-intel')
-- ! pywhl('3.11' 311 'arm64'      'macosx_arm64'      'macos-latest')
-- ! pywhl('3.11' 311 'universal2' 'macosx_universal2' 'macos-latest')
+- :: pywhl('3.11' 311 'x86_64'     'manylinux_x86_64'  'ubuntu-24.04')
+- :: pywhl('3.11' 311 'i686'       'manylinux_i686'    'ubuntu-24.04')
+- :: pywhl('3.11' 311 'aarch64'    'manylinux_aarch64' 'ubuntu-24.04-arm')
+- :: pywhl('3.11' 311 'x86_64'     'macosx_x86_64'     'macos-15-intel')
+- :: pywhl('3.11' 311 'arm64'      'macosx_arm64'      'macos-latest')
+- :: pywhl('3.11' 311 'universal2' 'macosx_universal2' 'macos-latest')
 #          pyv        arch         platform            os
-- ! pywhl('3.10' 310 'x86_64'     'manylinux_x86_64'  'ubuntu-24.04')
-- ! pywhl('3.10' 310 'i686'       'manylinux_i686'    'ubuntu-24.04')
-- ! pywhl('3.10' 310 'aarch64'    'manylinux_aarch64' 'ubuntu-24.04-arm')
-- ! pywhl('3.10' 310 'x86_64'     'macosx_x86_64'     'macos-15-intel')
-- ! pywhl('3.10' 310 'arm64'      'macosx_arm64'      'macos-latest')
-- ! pywhl('3.10' 310 'universal2' 'macosx_universal2' 'macos-latest')
+- :: pywhl('3.10' 310 'x86_64'     'manylinux_x86_64'  'ubuntu-24.04')
+- :: pywhl('3.10' 310 'i686'       'manylinux_i686'    'ubuntu-24.04')
+- :: pywhl('3.10' 310 'aarch64'    'manylinux_aarch64' 'ubuntu-24.04-arm')
+- :: pywhl('3.10' 310 'x86_64'     'macosx_x86_64'     'macos-15-intel')
+- :: pywhl('3.10' 310 'arm64'      'macosx_arm64'      'macos-latest')
+- :: pywhl('3.10' 310 'universal2' 'macosx_universal2' 'macos-latest')
 #          pyv        arch         platform            os
-- ! pywhl('3.9'  39  'x86_64'     'manylinux_x86_64'  'ubuntu-24.04')
-- ! pywhl('3.9'  39  'i686'       'manylinux_i686'    'ubuntu-24.04')
-- ! pywhl('3.9'  39  'aarch64'    'manylinux_aarch64' 'ubuntu-24.04-arm')
-- ! pywhl('3.9'  39  'x86_64'     'macosx_x86_64'     'macos-15-intel')
-- ! pywhl('3.9'  39  'arm64'      'macosx_arm64'      'macos-latest')
-- ! pywhl('3.9'  39  'universal2' 'macosx_universal2' 'macos-latest')
+- :: pywhl('3.9'  39  'x86_64'     'manylinux_x86_64'  'ubuntu-24.04')
+- :: pywhl('3.9'  39  'i686'       'manylinux_i686'    'ubuntu-24.04')
+- :: pywhl('3.9'  39  'aarch64'    'manylinux_aarch64' 'ubuntu-24.04-arm')
+- :: pywhl('3.9'  39  'x86_64'     'macosx_x86_64'     'macos-15-intel')
+- :: pywhl('3.9'  39  'arm64'      'macosx_arm64'      'macos-latest')
+- :: pywhl('3.9'  39  'universal2' 'macosx_universal2' 'macos-latest')
 #          pyv        arch         platform            os
-- ! pywhl('3.8'  38  'x86_64'     'manylinux_x86_64'  'ubuntu-24.04')
-- ! pywhl('3.8'  38  'i686'       'manylinux_i686'    'ubuntu-24.04')
-- ! pywhl('3.8'  38  'aarch64'    'manylinux_aarch64' 'ubuntu-24.04-arm')
-- ! pywhl('3.8'  38  'x86_64'     'macosx_x86_64'     'macos-15-intel')
-#- ! pywhl('3.8'  38  'arm64'      'macosx_arm64'      'macos-14'    ) # disabled: https://cibuildwheel.pypa.io/en/stable/faq/#macos-building-cpython-38-wheels-on-arm64
-#- ! pywhl('3.8'  38  'universal2' 'macosx_universal2' 'macos-14'    ) # disabled: https://cibuildwheel.pypa.io/en/stable/faq/#macos-building-cpython-38-wheels-on-arm64
+- :: pywhl('3.8'  38  'x86_64'     'manylinux_x86_64'  'ubuntu-24.04')
+- :: pywhl('3.8'  38  'i686'       'manylinux_i686'    'ubuntu-24.04')
+- :: pywhl('3.8'  38  'aarch64'    'manylinux_aarch64' 'ubuntu-24.04-arm')
+- :: pywhl('3.8'  38  'x86_64'     'macosx_x86_64'     'macos-15-intel')
+#- :: pywhl('3.8'  38  'arm64'      'macosx_arm64'      'macos-14'    ) # disabled: https://cibuildwheel.pypa.io/en/stable/faq/#macos-building-cpython-38-wheels-on-arm64
+#- :: pywhl('3.8'  38  'universal2' 'macosx_universal2' 'macos-14'    ) # disabled: https://cibuildwheel.pypa.io/en/stable/faq/#macos-building-cpython-38-wheels-on-arm64
 #          pyv        arch         platform            os
-- ! pywhl('3.7'  37  'x86_64'     'manylinux_x86_64'  'ubuntu-22.04')
-- ! pywhl('3.7'  37  'i686'       'manylinux_i686'    'ubuntu-22.04')
-- ! pywhl('3.7'  37  'x86_64'     'macosx_x86_64'     'macos-15-intel')
+- :: pywhl('3.7'  37  'x86_64'     'manylinux_x86_64'  'ubuntu-22.04')
+- :: pywhl('3.7'  37  'i686'       'manylinux_i686'    'ubuntu-22.04')
+- :: pywhl('3.7'  37  'x86_64'     'macosx_x86_64'     'macos-15-intel')
 #          pyv        arch         platform            os
-#- ! pywhl('3.6'  36  'x86_64'     'manylinux_x86_64'  'ubuntu-20.04') # setup-python 3.6 requires ubuntu 20.04
-#- ! pywhl('3.6'  36  'i686'       'manylinux_i686'    'ubuntu-20.04') # setup-python 3.6 requires ubuntu 20.04
-#- ! pywhl('3.6'  36  'x86_64'     'macosx_x86_64'     'macos-15-intel')
+#- :: pywhl('3.6'  36  'x86_64'     'manylinux_x86_64'  'ubuntu-20.04') # setup-python 3.6 requires ubuntu 20.04
+#- :: pywhl('3.6'  36  'i686'       'manylinux_i686'    'ubuntu-20.04') # setup-python 3.6 requires ubuntu 20.04
+#- :: pywhl('3.6'  36  'x86_64'     'macosx_x86_64'     'macos-15-intel')
 
 
 python-wheel-matrix-win =::
 #          pyv        arch     platform     os             vsenvarch     cmakeflags
-- ! pywhl('3.13' 313 'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
-- ! pywhl('3.13' 313 'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
-#- ! pywhl('3.13' 313 'ARM64'  'win_arm64'  'windows-2022' 'amd64_arm64' '-G "Visual Studio 17 2022" -A ARM64')
+- :: pywhl('3.13' 313 'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
+- :: pywhl('3.13' 313 'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
+#- :: pywhl('3.13' 313 'ARM64'  'win_arm64'  'windows-2022' 'amd64_arm64' '-G "Visual Studio 17 2022" -A ARM64')
 #
-- ! pywhl('3.12' 312 'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
-- ! pywhl('3.12' 312 'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
-#- ! pywhl('3.12' 312 'ARM64'  'win_arm64'  'windows-2022' 'amd64_arm64' '-G "Visual Studio 17 2022" -A ARM64')
+- :: pywhl('3.12' 312 'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
+- :: pywhl('3.12' 312 'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
+#- :: pywhl('3.12' 312 'ARM64'  'win_arm64'  'windows-2022' 'amd64_arm64' '-G "Visual Studio 17 2022" -A ARM64')
 #
-- ! pywhl('3.11' 311 'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
-- ! pywhl('3.11' 311 'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
-#- ! pywhl('3.11' 311 'ARM64'  'win_arm64'  'windows-2022' 'amd64_arm64' '-G "Visual Studio 17 2022" -A ARM64')
+- :: pywhl('3.11' 311 'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
+- :: pywhl('3.11' 311 'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
+#- :: pywhl('3.11' 311 'ARM64'  'win_arm64'  'windows-2022' 'amd64_arm64' '-G "Visual Studio 17 2022" -A ARM64')
 #
-- ! pywhl('3.10' 310 'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
-- ! pywhl('3.10' 310 'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
-#- ! pywhl('3.10' 310 'ARM64'  'win_arm64'  'windows-2022' 'amd64_arm64' '-G "Visual Studio 17 2022" -A ARM64')
+- :: pywhl('3.10' 310 'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
+- :: pywhl('3.10' 310 'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
+#- :: pywhl('3.10' 310 'ARM64'  'win_arm64'  'windows-2022' 'amd64_arm64' '-G "Visual Studio 17 2022" -A ARM64')
 #
-- ! pywhl('3.9'  39  'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
-- ! pywhl('3.9'  39  'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
-#- ! pywhl('3.9'  39  'ARM64'  'win_arm64'  'windows-2022' 'amd64_arm64' '-G "Visual Studio 17 2022" -A ARM64')
+- :: pywhl('3.9'  39  'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
+- :: pywhl('3.9'  39  'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
+#- :: pywhl('3.9'  39  'ARM64'  'win_arm64'  'windows-2022' 'amd64_arm64' '-G "Visual Studio 17 2022" -A ARM64')
 #
-- ! pywhl('3.8'  38  'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
-- ! pywhl('3.8'  38  'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
+- :: pywhl('3.8'  38  'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
+- :: pywhl('3.8'  38  'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
 #
-- ! pywhl('3.7'  37  'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
-#- ! pywhl('3.7'  37  'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
+- :: pywhl('3.7'  37  'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
+#- :: pywhl('3.7'  37  'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
 #
-- ! pywhl('3.6'  36  'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
-- ! pywhl('3.6'  36  'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
+- :: pywhl('3.6'  36  'AMD64'  'win_amd64'  'windows-2022' 'x64'         '-G "Visual Studio 17 2022" -A x64')
+- :: pywhl('3.6'  36  'x86'    'win32'      'windows-2022' 'x86'         '-G "Visual Studio 17 2022" -A Win32')
 
 
 setup-env =::
@@ -109,86 +110,84 @@ setup-env-win =::
   with:
     arch: ${{matrix.config.vsenvarch}}
 
+defn define-workflow-python-wheels(name matrix setup-env)::
+    :: setup-job('release' name)
+    name: ${{matrix.config.name}}
+    runs-on: ${{matrix.config.os}}
+    env:
+      CMAKE_FLAGS: ${{matrix.config.cmakeflags}} -DCMAKE_VERBOSE_MAKEFILES=ON -DRYML_DEV=OFF -DRYML_API_TESTS=OFF -DRYML_API_BENCHMARKS=OFF
+      CIBW_BUILD: cp${{matrix.config.cibw_pyv}}-${{matrix.config.cibw_platform}}
+      CIBW_ARCHS: ${{matrix.config.cibw_arch}}
+      CIBW_BUILD_VERBOSITY: 2
+    strategy:
+      fail-fast: false
+      matrix:
+        config:: matrix
+    steps:
+    - :: checkout-action + setup-env
+    - name: create wheel
+      uses: pypa/cibuildwheel@v2.23
+    - name: rename wheelhouse -> dist
+      run: mv -fv wheelhouse dist
+    - name: Verify artifacts
+      run: ls -lFhp dist/
+    - name: Save artifacts for publishing to PyPI
+      uses: actions/upload-artifact@v4
+      with: {name: 'dist-${{matrix.config.sfx}}', path: dist/}
+    # run the tests
+    - name: install python ${{matrix.config.pythonv}}
+      uses: actions/setup-python@v5
+      with:
+        python-version: ${{matrix.config.pythonv}}
+    - name: confirm python install
+      run: |
+        python --version
+        python -c 'import sys ; import struct ; import platform ; print("python:", sys.version, struct.calcsize("P") * 8, "bits", platform.machine())'
+    - name: test with python ${{matrix.config.pythonv}}
+      run: |
+        set -x
+        echo "python ${{matrix.config.pythonv}} ${{matrix.config.py_arch}} ${{matrix.config.cibw_arch}}"
+        # skip 32 bit tests, as Python 32 bits are not available in ubuntu
+        arch="${{matrix.config.cibw_arch}}"
+        if [ "$arch" == "x86" ] || [ "$arch" == "i686" ] ; then
+          exit 0
+        fi
+        python --version
+        python -c 'import sys ; import struct ; import platform ; print("python:", sys.version, struct.calcsize("P") * 8, "bits", platform.machine())'
+        pip --version
+        pip install -v -r requirements.txt
+        pip install -v -r api/python/requirements.txt
+        for whl in dist/* ; do
+          # verify that we can import the wheel files without installing the wheel
+          unzip -l $whl
+          mkdir -p tmpwhl
+          cd tmpwhl
+          unzip ../$whl
+          ls -lFpAR .
+          ( export PYTHONPATH=`pwd`/ryml ; python -c 'import ryml' )
+          cd ..
+          rm -rf tmpwhl
+          # verify that we can install the wheel and then import it
+          pip install -v $whl
+          pip show -f rapidyaml
+          python -c 'import ryml'
+          python -c 'import ryml ; print("ryml", ryml.version, ryml.version_tuple)'
+          python -c 'import ryml ; tree = ryml.parse_in_arena(b"{foo: bar}") ; assert tree.key(1) == b"foo" ; assert tree.val(1) == b"bar" ; print(str(tree.key(1), "utf8")) ; print(str(tree.val(1), "utf8"))'
+          # run the tests
+          python -m pytest -vvv api/python/tests
+          pip uninstall -y -v rapidyaml
+        done
+
 
 ---
-!yamlscript/v0:
+!ys:
+
+:use common:
 
-:use common: :all
 :workflow-setup 'release'::
   push:
     tags: [v0.*, v1.*, v2.*]
     branches: [master]
-::
-  defn define-workflow-python-wheels(name matrix setup-env)::
-      :: setup-job('release' name)
-      name: ${{matrix.config.name}}
-      runs-on: ${{matrix.config.os}}
-      env:
-        CMAKE_FLAGS: ${{matrix.config.cmakeflags}} -DCMAKE_VERBOSE_MAKEFILES=ON -DRYML_DEV=OFF -DRYML_API_TESTS=OFF -DRYML_API_BENCHMARKS=OFF
-        CIBW_BUILD: cp${{matrix.config.cibw_pyv}}-${{matrix.config.cibw_platform}}
-        CIBW_ARCHS: ${{matrix.config.cibw_arch}}
-        CIBW_BUILD_VERBOSITY: 2
-      strategy:
-        fail-fast: false
-        matrix:
-          config:: matrix
-      steps:
-      - :: checkout-action
-      - :: setup-env
-      - name: create wheel
-        uses: pypa/cibuildwheel@v2.23
-      - name: rename wheelhouse -> dist
-        run: mv -fv wheelhouse dist
-      - name: Verify artifacts
-        run: ls -lFhp dist/
-      - name: Save artifacts for publishing to PyPI
-        uses: actions/upload-artifact@v4
-        with: {name: 'dist-${{matrix.config.sfx}}', path: dist/}
-      # run the tests
-      - name: install python ${{matrix.config.pythonv}}
-        uses: actions/setup-python@v5
-        with:
-          python-version: ${{matrix.config.pythonv}}
-      - name: confirm python install
-        run: |
-          python --version
-          python -c 'import sys ; import struct ; import platform ; print("python:", sys.version, struct.calcsize("P") * 8, "bits", platform.machine())'
-      - name: test with python ${{matrix.config.pythonv}}
-        run: |
-          set -x
-          echo "python ${{matrix.config.pythonv}} ${{matrix.config.py_arch}} ${{matrix.config.cibw_arch}}"
-          # skip 32 bit tests, as Python 32 bits are not available in ubuntu
-          arch="${{matrix.config.cibw_arch}}"
-          if [ "$arch" == "x86" ] || [ "$arch" == "i686" ] ; then
-            exit 0
-          fi
-          python --version
-          python -c 'import sys ; import struct ; import platform ; print("python:", sys.version, struct.calcsize("P") * 8, "bits", platform.machine())'
-          pip --version
-          pip install -v -r requirements.txt
-          pip install -v -r api/python/requirements.txt
-          for whl in dist/* ; do
-            # verify that we can import the wheel files without installing the wheel
-            unzip -l $whl
-            mkdir -p tmpwhl
-            cd tmpwhl
-            unzip ../$whl
-            ls -lFpAR .
-            ( export PYTHONPATH=`pwd`/ryml ; python -c 'import ryml' )
-            cd ..
-            rm -rf tmpwhl
-            # verify that we can install the wheel and then import it
-            pip install -v $whl
-            pip show -f rapidyaml
-            python -c 'import ryml'
-            python -c 'import ryml ; print("ryml", ryml.version, ryml.version_tuple)'
-            python -c 'import ryml ; tree = ryml.parse_in_arena(b"{foo: bar}") ; assert tree.key(1) == b"foo" ; assert tree.val(1) == b"bar" ; print(str(tree.key(1), "utf8")) ; print(str(tree.val(1), "utf8"))'
-            # run the tests
-            python -m pytest -vvv api/python/tests
-            pip uninstall -y -v rapidyaml
-          done
-
-  =>: nil # this is needed to expose the function above
 
 env:
   PROJ_PKG_NAME: rapidyaml-
@@ -306,7 +305,7 @@ jobs:
         mkdir -p assets
         asset_src=`ls -1 ./build/shared64/*-${{matrix.config.sfxg}}`
         asset_dst=./assets/${PROJ_PKG_NAME}${SRC_VERSION}-${{matrix.config.sfxp}}
-        [ ! -f $asset_src ] && exit 1
+        [ -f $asset_src ] || exit
         cp -fav $asset_src $asset_dst
     - name: Save artifacts
       uses: actions/upload-artifact@v4
diff --git a/.github/workflows-in/samples.ys b/.github/workflows-in/samples.ys
index 6ad6fedff..47536c971 100644
--- a/.github/workflows-in/samples.ys
+++ b/.github/workflows-in/samples.ys
@@ -1,6 +1,6 @@
-!yamlscript/v0:
+!ys-0:
 
-:use common: :all
+:use common:
 :: workflow-setup()
 
 jobs:
@@ -18,7 +18,7 @@ jobs:
         - {bt: Debug  , os: macos-latest}
         - {bt: Release, os: macos-latest}
     env: !:merge*
-    - ! load('share/env.yaml')
+    - :: load('share/env.yaml')
     - CMANY: ON
     steps:
     - :: checkout-action
@@ -48,14 +48,9 @@ jobs:
     - name: custom_c4core
       run: cd samples/custom_c4core && ./run.sh $BT
     - name: fetch_content
-      run: |
-        # run this sample only if the branch exists on the repo
-        set -xe
+      run:: |
+        set -xeo pipefail
         cd samples/fetch_content
-        repo=$GITHUB_SERVER_URL/$GITHUB_REPOSITORY
-        # https://stackoverflow.com/questions/58033366
-        branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
-        echo branch=$branch
-        if [ ! -z "$(git ls-remote $repo | grep $branch)" ] ; then
-           ./run.sh $BT $branch "$repo"
-        fi
+        ${checkout-find-branch}
+        # run this sample only if the branch exists on the repo
+        ./run.sh \$BT \$hash "\$repo" || echo 'maybe some other time'
diff --git a/.github/workflows-in/windows.ys b/.github/workflows-in/windows.ys
index 8ca40aa9e..9e79d0541 100644
--- a/.github/workflows-in/windows.ys
+++ b/.github/workflows-in/windows.ys
@@ -1,6 +1,6 @@
-!yamlscript/v0:  # data mode
+!ys-0:
 
-:use common: :all
+:use common:
 :: workflow-setup()
 
 items =::
diff --git a/.github/workflows-in/ys/common.ys b/.github/workflows-in/ys/common.ys
index a25ffacee..98d88524e 100644
--- a/.github/workflows-in/ys/common.ys
+++ b/.github/workflows-in/ys/common.ys
@@ -1,11 +1,10 @@
-!yamlscript/v0
+!ys-0
 
 ns: common
 
 #----------------------------------------------------------
 defn workflow-setup(name=nil overrides={})::
-  name =: name || FILE.replace(/.*\//).replace(/\.ys$/)
-  name:: name
+  name:: name || FILE.replace(/.*\//).replace(/\.ys$/)
   defaults:
     run:
       # Use a bash shell so we can use the same syntax for environment
@@ -27,11 +26,6 @@ defn workflow-setup(name=nil overrides={})::
     NUM_JOBS_BUILD: # 4
 
 
-#----------------------------------------------------------
-defn bash(name):
-  slurp: "bash/$name.bash"
-
-
 #----------------------------------------------------------
 defn setup-job(workflowname jobname)::
   if: always()  # https://stackoverflow.com/a/62112985/721703
@@ -79,48 +73,64 @@ checkout-action-docker =::
 
 #----------------------------------------------------------
 
+# this is a bash block to compute the repo and branch for manual
+# checkouts
+checkout-find-branch =:: |
+  env | sort
+  echo GITHUB_SERVER_URL=$GITHUB_SERVER_URL
+  echo GITHUB_REPOSITORY=$GITHUB_REPOSITORY
+  echo GITHUB_REF=$GITHUB_REF
+  echo GITHUB_REF_NAME=$GITHUB_REF_NAME
+  echo GITHUB_HEAD_REF=$GITHUB_HEAD_REF
+  repo=$GITHUB_SERVER_URL/$GITHUB_REPOSITORY
+  # check the branch
+  # https://stackoverflow.com/questions/58033366
+  branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
+  echo branch=$branch
+  localbranch=$branch
+  rembranch=$branch
+  # does the branch exist in the repo?
+  if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
+      echo "branch $branch does not exist on $repo"
+      # refs/pull/485/merge -> pull/485/head
+      branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
+      localbranch=$branch
+      rembranch=$branch
+      echo "... falling back to $branch"
+      # does the fallback exist?
+      if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
+          echo "branch $branch does not exist on $repo"
+          exit 1
+      else
+          echo "branch $branch exists on $repo"
+          localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
+          echo "naming locally as $localbranch"
+          rembranch=$branch
+          branch=$branch:$localbranch
+      fi
+  fi
+  hash=$(git ls-remote $repo | grep -F $rembranch | awk '{print $1}')
+  echo "final repo=$repo"
+  echo "final branch=$branch"
+  echo "final rembranch=$rembranch"
+  echo "final localbranch=$localbranch"
+  echo "final hash=$hash"
+
 checkout-manual =::
 # This provides a manual checkout, needed because the nodejs version
 # prevents use of checkout@v3/v4 action on ubuntu18.04
 - name: checkout (manually)
-  run: |
+  run:: |
     set -xeo pipefail
-    env | sort
-    echo GITHUB_SERVER_URL=$GITHUB_SERVER_URL
-    echo GITHUB_REPOSITORY=$GITHUB_REPOSITORY
-    echo GITHUB_REF=$GITHUB_REF
-    echo GITHUB_REF_NAME=$GITHUB_REF_NAME
-    echo GITHUB_HEAD_REF=$GITHUB_HEAD_REF
-    repo=$GITHUB_SERVER_URL/$GITHUB_REPOSITORY
-    # check the branch
-    # https://stackoverflow.com/questions/58033366
-    branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
-    echo branch=$branch
-    # does the branch exist in the repo?
-    if [ -z "$(git ls-remote $repo | grep $branch)" ] ; then
-        echo "branch $branch does not exist on $repo"
-        # refs/pull/485/merge -> pull/485/head
-        branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
-        echo "... falling back to $branch"
-        # does the fallback exist?
-        if [ -z "(git ls-remote $repo | grep $branch)" ] ; then
-            echo "branch $branch does not exist on $repo"
-            exit 1
-        else
-            echo "branch $branch exists on $repo"
-            localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
-            branch=$branch:$localbranch
-            echo "naming locally as $branch"
-        fi
-    fi
+    ${checkout-find-branch}
     # finally, create the local repo
     git init -q .
     # needed for running in the docker image.
     # see https://github.com/actions/checkout/issues/1169
     git config --system --add safe.directory '*'
     # finally, do it!
-    git remote add origin $repo
-    git fetch origin $branch
+    git remote add origin \$repo
+    git fetch origin \$branch
     git reset --hard FETCH_HEAD
     git submodule update --init --recursive
     # show the log
@@ -269,7 +279,7 @@ defn run-manual-with-flags(cxx cc buildtype flags="")::
 # $(<expr>) is the more general syntax for any expr
 # $name and ${name} for simple var expansion
 # those are the 4 interpolation forms
-- name:: "---------------------------------------------------------"
+- name: ---------------------------------------------------------
   run:: |
     echo "$buildtype ::: $flags"
 - name:: "configure $buildtype ::: $flags"
@@ -300,7 +310,7 @@ defn run-manual-with-flags(cxx cc buildtype flags="")::
 
 
 defn run-vs-manual-with-flags(gen arch buildtype shared flags="")::
-- name:: "---------------------------------------------------------"
+- name: ---------------------------------------------------------
   run:: |
     echo "$buildtype ::: $flags shared=$shared"
 - name:: "configure $buildtype ::: $flags shared=$shared"
diff --git a/.github/workflows/api.yml b/.github/workflows/api.yml
index 11d84ad1b..c0eda84a7 100644
--- a/.github/workflows/api.yml
+++ b/.github/workflows/api.yml
@@ -22,7 +22,6 @@ jobs:
   pybare:
     if: always()
     continue-on-error: false
-    name: pybare/${{matrix.config.pythonv}}/${{matrix.config.os}}
     runs-on: ${{matrix.config.os}}
     strategy:
       fail-fast: false
@@ -73,10 +72,10 @@ jobs:
       run: |
         export PYTHONPATH=`pwd`/build/py/api/python3:$PYTHONPATH
         python -m pytest -vvv api/python/tests
+    name: pybare/${{matrix.config.pythonv}}/${{matrix.config.os}}
   pywheel:
     if: always()
     continue-on-error: false
-    name: pywheel/${{matrix.config.pythonv}}/${{matrix.config.os}}
     runs-on: ${{matrix.config.os}}
     strategy:
       fail-fast: false
@@ -140,10 +139,10 @@ jobs:
       run: pip install dist/*.whl
     - name: test with pytest
       run: python -m pytest -vvv api/python/tests
+    name: pywheel/${{matrix.config.pythonv}}/${{matrix.config.os}}
   pywheelwin:
     if: always()
     continue-on-error: false
-    name: pywheel/${{matrix.config.pythonv}}/${{matrix.config.os}}
     runs-on: ${{matrix.config.os}}
     strategy:
       fail-fast: false
@@ -210,3 +209,4 @@ jobs:
       run: pip install dist/*.whl
     - name: test with pytest
       run: python -m pytest -vvv api/python/tests
+    name: pywheel/${{matrix.config.pythonv}}/${{matrix.config.os}}
diff --git a/.github/workflows/benchmarks.yml b/.github/workflows/benchmarks.yml
index ffe75d2e5..0735ec9bd 100644
--- a/.github/workflows/benchmarks.yml
+++ b/.github/workflows/benchmarks.yml
@@ -85,8 +85,6 @@ jobs:
     - name: Verify vars.sh
       run: env | grep SRC
   benchmarks:
-    name: bm/c++${{matrix.std}}/${{matrix.comp}}/${{matrix.bt}}
-    needs: gettag
     if: always()
     continue-on-error: false
     runs-on: ${{matrix.os}}
@@ -200,3 +198,5 @@ jobs:
       with:
         name: ryml-benchmark_results-${{strategy.job-index}}
         path: ryml-benchmark_results/
+    name: bm/c++${{matrix.std}}/${{matrix.comp}}/${{matrix.bt}}
+    needs: gettag
diff --git a/.github/workflows/clang.yml b/.github/workflows/clang.yml
index 15c209d14..8d207e8cf 100644
--- a/.github/workflows/clang.yml
+++ b/.github/workflows/clang.yml
@@ -22,7 +22,6 @@ jobs:
   canary:
     if: always()
     continue-on-error: false
-    name: canary/${{matrix.cxx}}/c++${{matrix.std}}/${{matrix.bt}}
     runs-on: ubuntu-24.04
     container: ghcr.io/biojppm/c4core/ubuntu22.04:latest
     strategy:
@@ -88,10 +87,10 @@ jobs:
       run: source .github/setenv.sh && c4_run_test shared32
     - name: shared32-pack
       run: source .github/setenv.sh && c4_package shared32
+    name: canary/${{matrix.cxx}}/c++${{matrix.std}}/${{matrix.bt}}
   tabtokens:
     if: always()
     continue-on-error: false
-    name: tabtokens/${{matrix.cxx}}/c++${{matrix.std}}/${{matrix.bt}}
     runs-on: ubuntu-24.04
     container: ghcr.io/biojppm/c4core/ubuntu22.04:latest
     needs: canary
@@ -159,10 +158,10 @@ jobs:
       run: source .github/setenv.sh && c4_run_test shared32
     - name: shared32-pack
       run: source .github/setenv.sh && c4_package shared32
+    name: tabtokens/${{matrix.cxx}}/c++${{matrix.std}}/${{matrix.bt}}
   noexceptions:
     if: always()
     continue-on-error: false
-    name: noexceptions/${{matrix.cxx}}/c++${{matrix.std}}/${{matrix.bt}}
     runs-on: ubuntu-24.04
     container: ghcr.io/biojppm/c4core/ubuntu22.04:latest
     needs: canary
@@ -230,10 +229,10 @@ jobs:
       run: source .github/setenv.sh && c4_run_test shared32
     - name: shared32-pack
       run: source .github/setenv.sh && c4_package shared32
+    name: noexceptions/${{matrix.cxx}}/c++${{matrix.std}}/${{matrix.bt}}
   extended:
     if: always()
     continue-on-error: false
-    name: extended/${{matrix.cxx}}/${{matrix.bits}}bit/c++${{matrix.std}}/vg${{matrix.vg}}
     runs-on: ubuntu-24.04
     container: ghcr.io/biojppm/c4core/ubuntu${{matrix.img}}:latest
     needs: canary
@@ -450,23 +449,35 @@ jobs:
         # https://stackoverflow.com/questions/58033366
         branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
         echo branch=$branch
+        localbranch=$branch
+        rembranch=$branch
         # does the branch exist in the repo?
-        if [ -z "$(git ls-remote $repo | grep $branch)" ] ; then
+        if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
             echo "branch $branch does not exist on $repo"
             # refs/pull/485/merge -> pull/485/head
             branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
+            localbranch=$branch
+            rembranch=$branch
             echo "... falling back to $branch"
             # does the fallback exist?
-            if [ -z "(git ls-remote $repo | grep $branch)" ] ; then
+            if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
                 echo "branch $branch does not exist on $repo"
                 exit 1
             else
                 echo "branch $branch exists on $repo"
                 localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
+                echo "naming locally as $localbranch"
+                rembranch=$branch
                 branch=$branch:$localbranch
-                echo "naming locally as $branch"
             fi
         fi
+        hash=$(git ls-remote $repo | grep -F $rembranch | awk '{print $1}')
+        echo "final repo=$repo"
+        echo "final branch=$branch"
+        echo "final rembranch=$rembranch"
+        echo "final localbranch=$localbranch"
+        echo "final hash=$hash"
+
         # finally, create the local repo
         git init -q .
         # needed for running in the docker image.
@@ -626,10 +637,10 @@ jobs:
         source .github/setenv.sh
         export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
         cmake --build build/Release --target ryml-test-run
+    name: extended/${{matrix.cxx}}/${{matrix.bits}}bit/c++${{matrix.std}}/vg${{matrix.vg}}
   clangsan:
     if: always()
     continue-on-error: false
-    name: san/${{matrix.bt}}/c++${{matrix.std}}
     runs-on: ubuntu-24.04
     container: ghcr.io/biojppm/c4core/ubuntu22.04:latest
     needs: canary
@@ -752,3 +763,4 @@ jobs:
       run: source .github/setenv.sh && c4_run_test shared32
     - name: shared32-pack
       run: source .github/setenv.sh && c4_package shared32
+    name: san/${{matrix.bt}}/c++${{matrix.std}}
diff --git a/.github/workflows/embedded.yml b/.github/workflows/embedded.yml
index bc096a824..abf056af5 100644
--- a/.github/workflows/embedded.yml
+++ b/.github/workflows/embedded.yml
@@ -189,9 +189,6 @@ jobs:
         export CTEST_PARALLEL_LEVEL=`nproc`
         cmake --build build --target ryml-test-run
   xcompile11:
-    needs:
-    - canary11
-    - canary20
     if: always()
     continue-on-error: false
     name: ${{matrix.arch}}/c++11
@@ -304,10 +301,10 @@ jobs:
       run: |
         export CTEST_PARALLEL_LEVEL=`nproc`
         cmake --build build --target ryml-test-run
-  xcompile20:
     needs:
     - canary11
     - canary20
+  xcompile20:
     if: always()
     continue-on-error: false
     name: ${{matrix.arch}}/c++20
@@ -425,3 +422,6 @@ jobs:
       run: |
         export CTEST_PARALLEL_LEVEL=`nproc`
         cmake --build build --target ryml-test-run
+    needs:
+    - canary11
+    - canary20
diff --git a/.github/workflows/emscripten.yml b/.github/workflows/emscripten.yml
index f5c829664..efd332ccf 100644
--- a/.github/workflows/emscripten.yml
+++ b/.github/workflows/emscripten.yml
@@ -20,7 +20,6 @@ env:
   NUM_JOBS_BUILD: null
 jobs:
   emscripten:
-    name: emscripten/${{matrix.emver}}/c++${{matrix.std}}/${{matrix.bt}}
     if: ${{ false }}
     continue-on-error: false
     runs-on: ${{matrix.os}}
@@ -87,3 +86,4 @@ jobs:
       run: source .github/setenv.sh && c4_build_test static32
     - name: static32-run
       run: source .github/setenv.sh && c4_run_test static32
+    name: emscripten/${{matrix.emver}}/c++${{matrix.std}}/${{matrix.bt}}
diff --git a/.github/workflows/gcc.yml b/.github/workflows/gcc.yml
index 0e46b66a9..eb9ddaf92 100644
--- a/.github/workflows/gcc.yml
+++ b/.github/workflows/gcc.yml
@@ -19,56 +19,56 @@ env:
   CMAKE_FLAGS: -DRYML_TEST_SUITE=ON
   NUM_JOBS_BUILD: null
 jobs:
-  canary:
+  vg1:
     if: always()
     continue-on-error: false
-    name: canary/${{matrix.cxx}}/c++${{matrix.std}}/${{matrix.bt}}
     runs-on: ubuntu-24.04
     container: ghcr.io/biojppm/c4core/ubuntu${{matrix.img}}:latest
+    needs: canary
     strategy:
       fail-fast: false
       matrix:
         include:
-        - std: 11
-          cxx: g++-13
-          bt: Debug
-          bitlinks: shared64 static32
-          img: '22.04'
-        - std: 11
-          cxx: g++-13
-          bt: Release
-          bitlinks: shared64 static32
-          img: '22.04'
         - std: 20
-          cxx: g++-13
-          bt: Debug
-          bitlinks: shared64 static32
-          img: '22.04'
+          cxx: 14
+          bits: 64
+          vg: 'ON'
+          img: 22.04
         - std: 20
-          cxx: g++-13
-          bt: Release
-          bitlinks: shared64 static32
-          img: '22.04'
-        - std: 11
-          cxx: g++-5
-          bt: Debug
-          bitlinks: shared64 static32
-          img: '18.04'
-        - std: 11
-          cxx: g++-5
-          bt: Release
-          bitlinks: shared64 static32
-          img: '18.04'
+          cxx: 14
+          bits: 32
+          vg: 'ON'
+          img: 22.04
+        - std: 17
+          cxx: 14
+          bits: 64
+          vg: 'ON'
+          img: 22.04
+        - std: 17
+          cxx: 14
+          bits: 32
+          vg: 'ON'
+          img: 22.04
+        - std: 14
+          cxx: 14
+          bits: 64
+          vg: 'ON'
+          img: 22.04
+        - std: 14
+          cxx: 14
+          bits: 32
+          vg: 'ON'
+          img: 22.04
         - std: 11
-          cxx: g++-4.8
-          bt: Debug
-          bitlinks: shared64 static32
-          img: '18.04'
+          cxx: 14
+          bits: 64
+          vg: 'ON'
+          img: 22.04
         - std: 11
-          cxx: g++-4.8
-          bt: Release
-          bitlinks: shared64 static32
-          img: '18.04'
+          cxx: 14
+          bits: 32
+          vg: 'ON'
+          img: 22.04
     env:
       STD: ${{matrix.std}}
       CXX_: ${{matrix.cxx}}
@@ -93,23 +93,35 @@ jobs:
         # https://stackoverflow.com/questions/58033366
         branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
         echo branch=$branch
+        localbranch=$branch
+        rembranch=$branch
         # does the branch exist in the repo?
-        if [ -z "$(git ls-remote $repo | grep $branch)" ] ; then
+        if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
             echo "branch $branch does not exist on $repo"
             # refs/pull/485/merge -> pull/485/head
             branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
+            localbranch=$branch
+            rembranch=$branch
             echo "... falling back to $branch"
             # does the fallback exist?
-            if [ -z "(git ls-remote $repo | grep $branch)" ] ; then
+            if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
                 echo "branch $branch does not exist on $repo"
                 exit 1
             else
                 echo "branch $branch exists on $repo"
                 localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
+                echo "naming locally as $localbranch"
+                rembranch=$branch
                 branch=$branch:$localbranch
-                echo "naming locally as $branch"
             fi
         fi
+        hash=$(git ls-remote $repo | grep -F $rembranch | awk '{print $1}')
+        echo "final repo=$repo"
+        echo "final branch=$branch"
+        echo "final rembranch=$rembranch"
+        echo "final localbranch=$localbranch"
+        echo "final hash=$hash"
+
         # finally, create the local repo
         git init -q .
         # needed for running in the docker image.
@@ -127,45 +139,96 @@ jobs:
             || echo -n
         # show the last commit
         git log --name-status HEAD^..HEAD
-    - run: c4core-install ${{matrix.cxx}}
-    - name: show info
-      run: source .github/setenv.sh && c4_show_info
-    - name: shared64-configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test shared64
-    - name: shared64-build
-      run: source .github/setenv.sh && c4_build_test shared64
-    - name: shared64-run
-      run: source .github/setenv.sh && c4_run_test shared64
-    - name: shared64-pack
-      run: source .github/setenv.sh && c4_package shared64
-    - name: static64-configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test static64
-    - name: static64-build
-      run: source .github/setenv.sh && c4_build_test static64
-    - name: static64-run
-      run: source .github/setenv.sh && c4_run_test static64
-    - name: static64-pack
-      run: source .github/setenv.sh && c4_package static64
-    - name: static32-configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test static32
-    - name: static32-build
-      run: source .github/setenv.sh && c4_build_test static32
-    - name: static32-run
-      run: source .github/setenv.sh && c4_run_test static32
-    - name: static32-pack
-      run: source .github/setenv.sh && c4_package static32
-    - name: shared32-configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test shared32
-    - name: shared32-build
-      run: source .github/setenv.sh && c4_build_test shared32
-    - name: shared32-run
-      run: source .github/setenv.sh && c4_run_test shared32
-    - name: shared32-pack
-      run: source .github/setenv.sh && c4_package shared32
-  tabtokens:
+    - name: install
+      run: c4core-install g++-${{matrix.cxx}}
+    - name: '---------------------------------------------------------'
+      run: |
+        echo "Debug ::: -m${{matrix.bits}}"
+    - name: 'configure Debug ::: -m${{matrix.bits}}'
+      run: |
+        rm -rf build/Debug
+        export C4_EXTERN_DIR=`pwd`/build/extern
+        cmake -S . -B build/Debug \
+          -DCMAKE_CXX_COMPILER=g++-${{matrix.cxx}} \
+          -DCMAKE_C_COMPILER=gcc-${{matrix.cxx}} \
+          -DCMAKE_BUILD_TYPE=Debug \
+          -DCMAKE_CXX_FLAGS_DEBUG="-m${{matrix.bits}}" \
+          -DCMAKE_C_FLAGS_DEBUG="-m${{matrix.bits}}" \
+          -DC4_CXX_STANDARD=${{matrix.std}} \
+          -DRYML_CXX_STANDARD=${{matrix.std}} \
+          -DRYML_BUILD_TESTS=ON \
+          -DRYML_VALGRIND=${{matrix.vg}} \
+          -DRYML_DEV=ON \
+          -DRYML_BUILD_BENCHMARKS=OFF \
+          -DRYML_DBG=OFF
+    - name: 'build Debug ::: -m${{matrix.bits}}'
+      run: |
+        cmake --build build/Debug --target ryml-test-build --parallel --verbose
+    - name: 'run Debug ::: -m${{matrix.bits}}'
+      run: |
+        source .github/setenv.sh
+        export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
+        cmake --build build/Debug --target ryml-test-run
+    - name: '---------------------------------------------------------'
+      run: |
+        echo "Release ::: -O1 -DNDEBUG -m${{matrix.bits}}"
+    - name: 'configure Release ::: -O1 -DNDEBUG -m${{matrix.bits}}'
+      run: |
+        rm -rf build/Release
+        export C4_EXTERN_DIR=`pwd`/build/extern
+        cmake -S . -B build/Release \
+          -DCMAKE_CXX_COMPILER=g++-${{matrix.cxx}} \
+          -DCMAKE_C_COMPILER=gcc-${{matrix.cxx}} \
+          -DCMAKE_BUILD_TYPE=Release \
+          -DCMAKE_CXX_FLAGS_RELEASE="-O1 -DNDEBUG -m${{matrix.bits}}" \
+          -DCMAKE_C_FLAGS_RELEASE="-O1 -DNDEBUG -m${{matrix.bits}}" \
+          -DC4_CXX_STANDARD=${{matrix.std}} \
+          -DRYML_CXX_STANDARD=${{matrix.std}} \
+          -DRYML_BUILD_TESTS=ON \
+          -DRYML_VALGRIND=${{matrix.vg}} \
+          -DRYML_DEV=ON \
+          -DRYML_BUILD_BENCHMARKS=OFF \
+          -DRYML_DBG=OFF
+    - name: 'build Release ::: -O1 -DNDEBUG -m${{matrix.bits}}'
+      run: |
+        cmake --build build/Release --target ryml-test-build --parallel --verbose
+    - name: 'run Release ::: -O1 -DNDEBUG -m${{matrix.bits}}'
+      run: |
+        source .github/setenv.sh
+        export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
+        cmake --build build/Release --target ryml-test-run
+    - name: '---------------------------------------------------------'
+      run: |
+        echo "Release ::: -O2 -DNDEBUG -m${{matrix.bits}}"
+    - name: 'configure Release ::: -O2 -DNDEBUG -m${{matrix.bits}}'
+      run: |
+        rm -rf build/Release
+        export C4_EXTERN_DIR=`pwd`/build/extern
+        cmake -S . -B build/Release \
+          -DCMAKE_CXX_COMPILER=g++-${{matrix.cxx}} \
+          -DCMAKE_C_COMPILER=gcc-${{matrix.cxx}} \
+          -DCMAKE_BUILD_TYPE=Release \
+          -DCMAKE_CXX_FLAGS_RELEASE="-O2 -DNDEBUG -m${{matrix.bits}}" \
+          -DCMAKE_C_FLAGS_RELEASE="-O2 -DNDEBUG -m${{matrix.bits}}" \
+          -DC4_CXX_STANDARD=${{matrix.std}} \
+          -DRYML_CXX_STANDARD=${{matrix.std}} \
+          -DRYML_BUILD_TESTS=ON \
+          -DRYML_VALGRIND=${{matrix.vg}} \
+          -DRYML_DEV=ON \
+          -DRYML_BUILD_BENCHMARKS=OFF \
+          -DRYML_DBG=OFF
+    - name: 'build Release ::: -O2 -DNDEBUG -m${{matrix.bits}}'
+      run: |
+        cmake --build build/Release --target ryml-test-build --parallel --verbose
+    - name: 'run Release ::: -O2 -DNDEBUG -m${{matrix.bits}}'
+      run: |
+        source .github/setenv.sh
+        export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
+        cmake --build build/Release --target ryml-test-run
+    name: extended/${{matrix.cxx}}/${{matrix.bits}}bit/c++${{matrix.std}}/vg/D_O1_O2
+  vg2:
     if: always()
     continue-on-error: false
-    name: tabtokens/${{matrix.cxx}}/c++${{matrix.std}}/${{matrix.bt}}
     runs-on: ubuntu-24.04
     container: ghcr.io/biojppm/c4core/ubuntu${{matrix.img}}:latest
     needs: canary
@@ -173,46 +236,46 @@ jobs:
       fail-fast: false
       matrix:
         include:
-        - std: 11
-          cxx: g++-13
-          bt: Debug
-          bitlinks: shared64 static32
-          img: '22.04'
-        - std: 11
-          cxx: g++-13
-          bt: Release
-          bitlinks: shared64 static32
-          img: '22.04'
         - std: 20
-          cxx: g++-13
-          bt: Debug
-          bitlinks: shared64 static32
-          img: '22.04'
+          cxx: 14
+          bits: 64
+          vg: 'ON'
+          img: 22.04
         - std: 20
-          cxx: g++-13
-          bt: Release
-          bitlinks: shared64 static32
-          img: '22.04'
+          cxx: 14
+          bits: 32
+          vg: 'ON'
+          img: 22.04
+        - std: 17
+          cxx: 14
+          bits: 64
+          vg: 'ON'
+          img: 22.04
+        - std: 17
+          cxx: 14
+          bits: 32
+          vg: 'ON'
+          img: 22.04
+        - std: 14
+          cxx: 14
+          bits: 64
+          vg: 'ON'
+          img: 22.04
+        - std: 14
+          cxx: 14
+          bits: 32
+          vg: 'ON'
+          img: 22.04
         - std: 11
-          cxx: g++-5
-          bt: Debug
-          bitlinks: shared64 static32
-          img: '18.04'
+          cxx: 14
+          bits: 64
+          vg: 'ON'
+          img: 22.04
         - std: 11
-          cxx: g++-5
-          bt: Release
-          bitlinks: shared64 static32
-          img: '18.04'
-        - std: 11
-          cxx: g++-4.8
-          bt: Debug
-          bitlinks: shared64 static32
-          img: '18.04'
-        - std: 11
-          cxx: g++-4.8
-          bt: Release
-          bitlinks: shared64 static32
-          img: '18.04'
+          cxx: 14
+          bits: 32
+          vg: 'ON'
+          img: 22.04
     env:
       STD: ${{matrix.std}}
       CXX_: ${{matrix.cxx}}
@@ -222,7 +285,6 @@ jobs:
       SAN: ${{matrix.san}}
       LINT: ${{matrix.lint}}
       OS: ${{matrix.os}}
-      CMAKE_FLAGS: -DRYML_WITH_TAB_TOKENS=ON
     steps:
     - name: checkout (manually)
       run: |
@@ -238,23 +300,35 @@ jobs:
         # https://stackoverflow.com/questions/58033366
         branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
         echo branch=$branch
+        localbranch=$branch
+        rembranch=$branch
         # does the branch exist in the repo?
-        if [ -z "$(git ls-remote $repo | grep $branch)" ] ; then
+        if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
             echo "branch $branch does not exist on $repo"
             # refs/pull/485/merge -> pull/485/head
             branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
+            localbranch=$branch
+            rembranch=$branch
             echo "... falling back to $branch"
             # does the fallback exist?
-            if [ -z "(git ls-remote $repo | grep $branch)" ] ; then
+            if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
                 echo "branch $branch does not exist on $repo"
                 exit 1
             else
                 echo "branch $branch exists on $repo"
                 localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
+                echo "naming locally as $localbranch"
+                rembranch=$branch
                 branch=$branch:$localbranch
-                echo "naming locally as $branch"
             fi
         fi
+        hash=$(git ls-remote $repo | grep -F $rembranch | awk '{print $1}')
+        echo "final repo=$repo"
+        echo "final branch=$branch"
+        echo "final rembranch=$rembranch"
+        echo "final localbranch=$localbranch"
+        echo "final hash=$hash"
+
         # finally, create the local repo
         git init -q .
         # needed for running in the docker image.
@@ -272,45 +346,68 @@ jobs:
             || echo -n
         # show the last commit
         git log --name-status HEAD^..HEAD
-    - run: c4core-install ${{matrix.cxx}}
-    - name: show info
-      run: source .github/setenv.sh && c4_show_info
-    - name: shared64-configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test shared64
-    - name: shared64-build
-      run: source .github/setenv.sh && c4_build_test shared64
-    - name: shared64-run
-      run: source .github/setenv.sh && c4_run_test shared64
-    - name: shared64-pack
-      run: source .github/setenv.sh && c4_package shared64
-    - name: static64-configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test static64
-    - name: static64-build
-      run: source .github/setenv.sh && c4_build_test static64
-    - name: static64-run
-      run: source .github/setenv.sh && c4_run_test static64
-    - name: static64-pack
-      run: source .github/setenv.sh && c4_package static64
-    - name: static32-configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test static32
-    - name: static32-build
-      run: source .github/setenv.sh && c4_build_test static32
-    - name: static32-run
-      run: source .github/setenv.sh && c4_run_test static32
-    - name: static32-pack
-      run: source .github/setenv.sh && c4_package static32
-    - name: shared32-configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test shared32
-    - name: shared32-build
-      run: source .github/setenv.sh && c4_build_test shared32
-    - name: shared32-run
-      run: source .github/setenv.sh && c4_run_test shared32
-    - name: shared32-pack
-      run: source .github/setenv.sh && c4_package shared32
-  noexceptions:
+    - name: install
+      run: c4core-install g++-${{matrix.cxx}}
+    - name: '---------------------------------------------------------'
+      run: |
+        echo "Release ::: -O3 -DNDEBUG -m${{matrix.bits}}"
+    - name: 'configure Release ::: -O3 -DNDEBUG -m${{matrix.bits}}'
+      run: |
+        rm -rf build/Release
+        export C4_EXTERN_DIR=`pwd`/build/extern
+        cmake -S . -B build/Release \
+          -DCMAKE_CXX_COMPILER=g++-${{matrix.cxx}} \
+          -DCMAKE_C_COMPILER=gcc-${{matrix.cxx}} \
+          -DCMAKE_BUILD_TYPE=Release \
+          -DCMAKE_CXX_FLAGS_RELEASE="-O3 -DNDEBUG -m${{matrix.bits}}" \
+          -DCMAKE_C_FLAGS_RELEASE="-O3 -DNDEBUG -m${{matrix.bits}}" \
+          -DC4_CXX_STANDARD=${{matrix.std}} \
+          -DRYML_CXX_STANDARD=${{matrix.std}} \
+          -DRYML_BUILD_TESTS=ON \
+          -DRYML_VALGRIND=${{matrix.vg}} \
+          -DRYML_DEV=ON \
+          -DRYML_BUILD_BENCHMARKS=OFF \
+          -DRYML_DBG=OFF
+    - name: 'build Release ::: -O3 -DNDEBUG -m${{matrix.bits}}'
+      run: |
+        cmake --build build/Release --target ryml-test-build --parallel --verbose
+    - name: 'run Release ::: -O3 -DNDEBUG -m${{matrix.bits}}'
+      run: |
+        source .github/setenv.sh
+        export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
+        cmake --build build/Release --target ryml-test-run
+    - name: '---------------------------------------------------------'
+      run: |
+        echo "Release ::: -Os -DNDEBUG -m${{matrix.bits}}"
+    - name: 'configure Release ::: -Os -DNDEBUG -m${{matrix.bits}}'
+      run: |
+        rm -rf build/Release
+        export C4_EXTERN_DIR=`pwd`/build/extern
+        cmake -S . -B build/Release \
+          -DCMAKE_CXX_COMPILER=g++-${{matrix.cxx}} \
+          -DCMAKE_C_COMPILER=gcc-${{matrix.cxx}} \
+          -DCMAKE_BUILD_TYPE=Release \
+          -DCMAKE_CXX_FLAGS_RELEASE="-Os -DNDEBUG -m${{matrix.bits}}" \
+          -DCMAKE_C_FLAGS_RELEASE="-Os -DNDEBUG -m${{matrix.bits}}" \
+          -DC4_CXX_STANDARD=${{matrix.std}} \
+          -DRYML_CXX_STANDARD=${{matrix.std}} \
+          -DRYML_BUILD_TESTS=ON \
+          -DRYML_VALGRIND=${{matrix.vg}} \
+          -DRYML_DEV=ON \
+          -DRYML_BUILD_BENCHMARKS=OFF \
+          -DRYML_DBG=OFF
+    - name: 'build Release ::: -Os -DNDEBUG -m${{matrix.bits}}'
+      run: |
+        cmake --build build/Release --target ryml-test-build --parallel --verbose
+    - name: 'run Release ::: -Os -DNDEBUG -m${{matrix.bits}}'
+      run: |
+        source .github/setenv.sh
+        export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
+        cmake --build build/Release --target ryml-test-run
+    name: extended/${{matrix.cxx}}/${{matrix.bits}}bit/c++${{matrix.std}}/vg/O3_Os
+  extended:
     if: always()
     continue-on-error: false
-    name: noexceptions/${{matrix.cxx}}/c++${{matrix.std}}/${{matrix.bt}}
     runs-on: ubuntu-24.04
     container: ghcr.io/biojppm/c4core/ubuntu${{matrix.img}}:latest
     needs: canary
@@ -319,45 +416,115 @@ jobs:
       matrix:
         include:
         - std: 11
-          cxx: g++-13
-          bt: Debug
-          bitlinks: shared64 static32
-          img: '22.04'
+          cxx: 13
+          bits: 64
+          vg: 'OFF'
+          img: 22.04
         - std: 11
-          cxx: g++-13
-          bt: Release
-          bitlinks: shared64 static32
-          img: '22.04'
-        - std: 20
-          cxx: g++-13
-          bt: Debug
-          bitlinks: shared64 static32
-          img: '22.04'
-        - std: 20
-          cxx: g++-13
-          bt: Release
-          bitlinks: shared64 static32
-          img: '22.04'
+          cxx: 13
+          bits: 32
+          vg: 'OFF'
+          img: 22.04
         - std: 11
-          cxx: g++-5
-          bt: Debug
-          bitlinks: shared64 static32
-          img: '18.04'
+          cxx: 12
+          bits: 64
+          vg: 'OFF'
+          img: 22.04
         - std: 11
-          cxx: g++-5
-          bt: Release
-          bitlinks: shared64 static32
-          img: '18.04'
+          cxx: 12
+          bits: 32
+          vg: 'OFF'
+          img: 22.04
         - std: 11
-          cxx: g++-4.8
-          bt: Debug
-          bitlinks: shared64 static32
-          img: '18.04'
+          cxx: 11
+          bits: 64
+          vg: 'OFF'
+          img: 22.04
         - std: 11
-          cxx: g++-4.8
-          bt: Release
-          bitlinks: shared64 static32
-          img: '18.04'
+          cxx: 11
+          bits: 32
+          vg: 'OFF'
+          img: 22.04
+        - std: 11
+          cxx: 10
+          bits: 64
+          vg: 'OFF'
+          img: 22.04
+        - std: 11
+          cxx: 10
+          bits: 32
+          vg: 'OFF'
+          img: 22.04
+        - std: 11
+          cxx: 9
+          bits: 64
+          vg: 'OFF'
+          img: 22.04
+        - std: 11
+          cxx: 9
+          bits: 32
+          vg: 'OFF'
+          img: 22.04
+        - std: 11
+          cxx: 8
+          bits: 64
+          vg: 'OFF'
+          img: 18.04
+        - std: 11
+          cxx: 8
+          bits: 32
+          vg: 'OFF'
+          img: 18.04
+        - std: 11
+          cxx: 7
+          bits: 64
+          vg: 'OFF'
+          img: 18.04
+        - std: 11
+          cxx: 7
+          bits: 32
+          vg: 'OFF'
+          img: 18.04
+        - std: 11
+          cxx: 6
+          bits: 64
+          vg: 'OFF'
+          img: 18.04
+        - std: 11
+          cxx: 6
+          bits: 32
+          vg: 'OFF'
+          img: 18.04
+        - std: 11
+          cxx: 5
+          bits: 64
+          vg: 'OFF'
+          img: 18.04
+        - std: 11
+          cxx: 5
+          bits: 32
+          vg: 'OFF'
+          img: 18.04
+        - std: 11
+          cxx: 4.9
+          bits: 64
+          vg: 'OFF'
+          img: 18.04
+        - std: 11
+          cxx: 4.9
+          bits: 32
+          vg: 'OFF'
+          img: 18.04
+        - std: 11
+          cxx: 4.8
+          bits: 64
+          vg: 'OFF'
+          img: 18.04
+        - std: 11
+          cxx: 4.8
+          bits: 32
+          vg: 'OFF'
+          img: 18.04
     env:
       STD: ${{matrix.std}}
       CXX_: ${{matrix.cxx}}
@@ -367,7 +534,6 @@ jobs:
       SAN: ${{matrix.san}}
       LINT: ${{matrix.lint}}
       OS: ${{matrix.os}}
-      CXXFLAGS: -fno-exceptions -fno-rtti
     steps:
     - name: checkout (manually)
       run: |
@@ -383,225 +549,35 @@ jobs:
         # https://stackoverflow.com/questions/58033366
         branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
         echo branch=$branch
+        localbranch=$branch
+        rembranch=$branch
         # does the branch exist in the repo?
-        if [ -z "$(git ls-remote $repo | grep $branch)" ] ; then
+        if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
             echo "branch $branch does not exist on $repo"
             # refs/pull/485/merge -> pull/485/head
             branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
+            localbranch=$branch
+            rembranch=$branch
             echo "... falling back to $branch"
             # does the fallback exist?
-            if [ -z "(git ls-remote $repo | grep $branch)" ] ; then
+            if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
                 echo "branch $branch does not exist on $repo"
                 exit 1
             else
                 echo "branch $branch exists on $repo"
                 localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
+                echo "naming locally as $localbranch"
+                rembranch=$branch
                 branch=$branch:$localbranch
-                echo "naming locally as $branch"
-            fi
-        fi
-        # finally, create the local repo
-        git init -q .
-        # needed for running in the docker image.
-        # see https://github.com/actions/checkout/issues/1169
-        git config --system --add safe.directory '*'
-        # finally, do it!
-        git remote add origin $repo
-        git fetch origin $branch
-        git reset --hard FETCH_HEAD
-        git submodule update --init --recursive
-        # show the log
-        git log --graph --date=relative --date-order --color=always \
-                --pretty='%C(yellow)%h %C(cyan)%cd %Cblue%aN%C(auto)%d %Creset%s' \
-            | head -30 \
-            || echo -n
-        # show the last commit
-        git log --name-status HEAD^..HEAD
-    - run: c4core-install ${{matrix.cxx}}
-    - name: show info
-      run: source .github/setenv.sh && c4_show_info
-    - name: shared64-configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test shared64
-    - name: shared64-build
-      run: source .github/setenv.sh && c4_build_test shared64
-    - name: shared64-run
-      run: source .github/setenv.sh && c4_run_test shared64
-    - name: shared64-pack
-      run: source .github/setenv.sh && c4_package shared64
-    - name: static64-configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test static64
-    - name: static64-build
-      run: source .github/setenv.sh && c4_build_test static64
-    - name: static64-run
-      run: source .github/setenv.sh && c4_run_test static64
-    - name: static64-pack
-      run: source .github/setenv.sh && c4_package static64
-    - name: static32-configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test static32
-    - name: static32-build
-      run: source .github/setenv.sh && c4_build_test static32
-    - name: static32-run
-      run: source .github/setenv.sh && c4_run_test static32
-    - name: static32-pack
-      run: source .github/setenv.sh && c4_package static32
-    - name: shared32-configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test shared32
-    - name: shared32-build
-      run: source .github/setenv.sh && c4_build_test shared32
-    - name: shared32-run
-      run: source .github/setenv.sh && c4_run_test shared32
-    - name: shared32-pack
-      run: source .github/setenv.sh && c4_package shared32
-  misbuild:
-    if: always()
-    continue-on-error: false
-    name: misbuild#${{matrix.issue}}/gcc${{matrix.gcc}}/c++${{matrix.std}}
-    runs-on: ubuntu-24.04
-    container: ghcr.io/biojppm/c4core/ubuntu${{matrix.img}}:latest
-    needs: canary
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-        - issue: 440
-          std: 11
-          gcc: 12
-          bt: Release
-          img: 22.04
-          cxxflags: -O2 -DNDEBUG -g
-        - issue: 486
-          std: 11
-          gcc: 11
-          bt: Release
-          img: 22.04
-          cxxflags: -O3 -DNDEBUG
-    env:
-      STD: ${{matrix.std}}
-      CXX_: ${{matrix.gcc}}
-      BT: ${{matrix.bt}}
-      BITLINKS: ${{matrix.bitlinks}}
-      VG: ${{matrix.vg}}
-      SAN: ${{matrix.san}}
-      LINT: ${{matrix.lint}}
-      OS: ${{matrix.os}}
-    steps:
-    - name: checkout (action + docker)
-      uses: actions/checkout@v4
-      with:
-        submodules: recursive
-        fetch-depth: 0
-    - run: git config --system --add safe.directory '*'
-    - run: c4core-install g++-${{matrix.gcc}}
-    - name: show info
-      run: source .github/setenv.sh && c4_show_info
-    - name: configure (issue \#${{matrix.issue}})
-      run: |
-        cmake -S . -B build \
-          -DCMAKE_CXX_COMPILER=g++-${{matrix.gcc}} \
-          -DCMAKE_C_COMPILER=gcc-${{matrix.gcc}} \
-          -DCMAKE_BUILD_TYPE=Release \
-          -DCMAKE_CXX_FLAGS_RELEASE="${{matrix.cxxflags}}" \
-          -DRYML_BUILD_TESTS=ON \
-          -DRYML_DBG=OFF
-    - name: build (issue \#${{matrix.issue}})
-      run: cmake --build build --target ryml-test-build --parallel --verbose
-    - name: run (issue \#${{matrix.issue}})
-      run: |
-        source .github/setenv.sh
-        export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
-        cmake --build build --target ryml-test-run
-  vg1:
-    if: always()
-    continue-on-error: false
-    name: extended/${{matrix.cxx}}/${{matrix.bits}}bit/c++${{matrix.std}}/vg/D_O1_O2
-    runs-on: ubuntu-24.04
-    container: ghcr.io/biojppm/c4core/ubuntu${{matrix.img}}:latest
-    needs: canary
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-        - std: 20
-          cxx: 14
-          bits: 64
-          vg: 'ON'
-          img: 22.04
-        - std: 20
-          cxx: 14
-          bits: 32
-          vg: 'ON'
-          img: 22.04
-        - std: 17
-          cxx: 14
-          bits: 64
-          vg: 'ON'
-          img: 22.04
-        - std: 17
-          cxx: 14
-          bits: 32
-          vg: 'ON'
-          img: 22.04
-        - std: 14
-          cxx: 14
-          bits: 64
-          vg: 'ON'
-          img: 22.04
-        - std: 14
-          cxx: 14
-          bits: 32
-          vg: 'ON'
-          img: 22.04
-        - std: 11
-          cxx: 14
-          bits: 64
-          vg: 'ON'
-          img: 22.04
-        - std: 11
-          cxx: 14
-          bits: 32
-          vg: 'ON'
-          img: 22.04
-    env:
-      STD: ${{matrix.std}}
-      CXX_: ${{matrix.cxx}}
-      BT: ${{matrix.bt}}
-      BITLINKS: ${{matrix.bitlinks}}
-      VG: ${{matrix.vg}}
-      SAN: ${{matrix.san}}
-      LINT: ${{matrix.lint}}
-      OS: ${{matrix.os}}
-    steps:
-    - name: checkout (manually)
-      run: |
-        set -xeo pipefail
-        env | sort
-        echo GITHUB_SERVER_URL=$GITHUB_SERVER_URL
-        echo GITHUB_REPOSITORY=$GITHUB_REPOSITORY
-        echo GITHUB_REF=$GITHUB_REF
-        echo GITHUB_REF_NAME=$GITHUB_REF_NAME
-        echo GITHUB_HEAD_REF=$GITHUB_HEAD_REF
-        repo=$GITHUB_SERVER_URL/$GITHUB_REPOSITORY
-        # check the branch
-        # https://stackoverflow.com/questions/58033366
-        branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
-        echo branch=$branch
-        # does the branch exist in the repo?
-        if [ -z "$(git ls-remote $repo | grep $branch)" ] ; then
-            echo "branch $branch does not exist on $repo"
-            # refs/pull/485/merge -> pull/485/head
-            branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
-            echo "... falling back to $branch"
-            # does the fallback exist?
-            if [ -z "(git ls-remote $repo | grep $branch)" ] ; then
-                echo "branch $branch does not exist on $repo"
-                exit 1
-            else
-                echo "branch $branch exists on $repo"
-                localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
-                branch=$branch:$localbranch
-                echo "naming locally as $branch"
             fi
         fi
+        hash=$(git ls-remote $repo | grep -F $rembranch | awk '{print $1}')
+        echo "final repo=$repo"
+        echo "final branch=$branch"
+        echo "final rembranch=$rembranch"
+        echo "final localbranch=$localbranch"
+        echo "final hash=$hash"
+
         # finally, create the local repo
         git init -q .
         # needed for running in the docker image.
@@ -705,117 +681,6 @@ jobs:
         source .github/setenv.sh
         export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
         cmake --build build/Release --target ryml-test-run
-  vg2:
-    if: always()
-    continue-on-error: false
-    name: extended/${{matrix.cxx}}/${{matrix.bits}}bit/c++${{matrix.std}}/vg/O3_Os
-    runs-on: ubuntu-24.04
-    container: ghcr.io/biojppm/c4core/ubuntu${{matrix.img}}:latest
-    needs: canary
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-        - std: 20
-          cxx: 14
-          bits: 64
-          vg: 'ON'
-          img: 22.04
-        - std: 20
-          cxx: 14
-          bits: 32
-          vg: 'ON'
-          img: 22.04
-        - std: 17
-          cxx: 14
-          bits: 64
-          vg: 'ON'
-          img: 22.04
-        - std: 17
-          cxx: 14
-          bits: 32
-          vg: 'ON'
-          img: 22.04
-        - std: 14
-          cxx: 14
-          bits: 64
-          vg: 'ON'
-          img: 22.04
-        - std: 14
-          cxx: 14
-          bits: 32
-          vg: 'ON'
-          img: 22.04
-        - std: 11
-          cxx: 14
-          bits: 64
-          vg: 'ON'
-          img: 22.04
-        - std: 11
-          cxx: 14
-          bits: 32
-          vg: 'ON'
-          img: 22.04
-    env:
-      STD: ${{matrix.std}}
-      CXX_: ${{matrix.cxx}}
-      BT: ${{matrix.bt}}
-      BITLINKS: ${{matrix.bitlinks}}
-      VG: ${{matrix.vg}}
-      SAN: ${{matrix.san}}
-      LINT: ${{matrix.lint}}
-      OS: ${{matrix.os}}
-    steps:
-    - name: checkout (manually)
-      run: |
-        set -xeo pipefail
-        env | sort
-        echo GITHUB_SERVER_URL=$GITHUB_SERVER_URL
-        echo GITHUB_REPOSITORY=$GITHUB_REPOSITORY
-        echo GITHUB_REF=$GITHUB_REF
-        echo GITHUB_REF_NAME=$GITHUB_REF_NAME
-        echo GITHUB_HEAD_REF=$GITHUB_HEAD_REF
-        repo=$GITHUB_SERVER_URL/$GITHUB_REPOSITORY
-        # check the branch
-        # https://stackoverflow.com/questions/58033366
-        branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
-        echo branch=$branch
-        # does the branch exist in the repo?
-        if [ -z "$(git ls-remote $repo | grep $branch)" ] ; then
-            echo "branch $branch does not exist on $repo"
-            # refs/pull/485/merge -> pull/485/head
-            branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
-            echo "... falling back to $branch"
-            # does the fallback exist?
-            if [ -z "(git ls-remote $repo | grep $branch)" ] ; then
-                echo "branch $branch does not exist on $repo"
-                exit 1
-            else
-                echo "branch $branch exists on $repo"
-                localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
-                branch=$branch:$localbranch
-                echo "naming locally as $branch"
-            fi
-        fi
-        # finally, create the local repo
-        git init -q .
-        # needed for running in the docker image.
-        # see https://github.com/actions/checkout/issues/1169
-        git config --system --add safe.directory '*'
-        # finally, do it!
-        git remote add origin $repo
-        git fetch origin $branch
-        git reset --hard FETCH_HEAD
-        git submodule update --init --recursive
-        # show the log
-        git log --graph --date=relative --date-order --color=always \
-                --pretty='%C(yellow)%h %C(cyan)%cd %Cblue%aN%C(auto)%d %Creset%s' \
-            | head -30 \
-            || echo -n
-        # show the last commit
-        git log --name-status HEAD^..HEAD
-    - name: install
-      run: c4core-install g++-${{matrix.cxx}}
     - name: '---------------------------------------------------------'
       run: |
         echo "Release ::: -O3 -DNDEBUG -m${{matrix.bits}}"
@@ -872,127 +737,81 @@ jobs:
         source .github/setenv.sh
         export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
         cmake --build build/Release --target ryml-test-run
-  extended:
+    name: extended/${{matrix.cxx}}/${{matrix.bits}}bit/c++${{matrix.std}}
+  gccsan:
     if: always()
     continue-on-error: false
-    name: extended/${{matrix.cxx}}/${{matrix.bits}}bit/c++${{matrix.std}}
     runs-on: ubuntu-24.04
-    container: ghcr.io/biojppm/c4core/ubuntu${{matrix.img}}:latest
+    container: ghcr.io/biojppm/c4core/ubuntu22.04:latest
     needs: canary
     strategy:
       fail-fast: false
       matrix:
         include:
         - std: 11
-          cxx: 13
-          bits: 64
-          vg: 'OFF'
-          img: 22.04
-        - std: 11
-          cxx: 13
-          bits: 32
-          vg: 'OFF'
-          img: 22.04
-        - std: 11
-          cxx: 12
-          bits: 64
-          vg: 'OFF'
-          img: 22.04
-        - std: 11
-          cxx: 12
-          bits: 32
-          vg: 'OFF'
-          img: 22.04
-        - std: 11
-          cxx: 11
-          bits: 64
-          vg: 'OFF'
-          img: 22.04
-        - std: 11
-          cxx: 11
-          bits: 32
-          vg: 'OFF'
-          img: 22.04
-        - std: 11
-          cxx: 10
-          bits: 64
-          vg: 'OFF'
-          img: 22.04
-        - std: 11
-          cxx: 10
-          bits: 32
-          vg: 'OFF'
-          img: 22.04
-        - std: 11
-          cxx: 9
-          bits: 64
-          vg: 'OFF'
-          img: 22.04
-        - std: 11
-          cxx: 9
-          bits: 32
-          vg: 'OFF'
-          img: 22.04
-        - std: 11
-          cxx: 8
-          bits: 64
-          vg: 'OFF'
-          img: 18.04
-        - std: 11
-          cxx: 8
-          bits: 32
-          vg: 'OFF'
-          img: 18.04
-        - std: 11
-          cxx: 7
-          bits: 64
-          vg: 'OFF'
-          img: 18.04
-        - std: 11
-          cxx: 7
-          bits: 32
-          vg: 'OFF'
-          img: 18.04
-        - std: 11
-          cxx: 6
-          bits: 64
-          vg: 'OFF'
-          img: 18.04
-        - std: 11
-          cxx: 6
-          bits: 32
-          vg: 'OFF'
-          img: 18.04
-        - std: 11
-          cxx: 5
-          bits: 64
-          vg: 'OFF'
-          img: 18.04
-        - std: 11
-          cxx: 5
-          bits: 32
-          vg: 'OFF'
-          img: 18.04
-        - std: 11
-          cxx: 4.9
-          bits: 64
-          vg: 'OFF'
-          img: 18.04
+          cxx: g++-14
+          bt: asan
+          bitlinks: static64
+        - std: 14
+          cxx: g++-14
+          bt: asan
+          bitlinks: static64
+        - std: 17
+          cxx: g++-14
+          bt: asan
+          bitlinks: static64
+        - std: 20
+          cxx: g++-14
+          bt: asan
+          bitlinks: static64
         - std: 11
-          cxx: 4.9
-          bits: 32
-          vg: 'OFF'
-          img: 18.04
+          cxx: g++-14
+          bt: lsan
+          bitlinks: static64
+        - std: 14
+          cxx: g++-14
+          bt: lsan
+          bitlinks: static64
+        - std: 17
+          cxx: g++-14
+          bt: lsan
+          bitlinks: static64
+        - std: 20
+          cxx: g++-14
+          bt: lsan
+          bitlinks: static64
         - std: 11
-          cxx: 4.8
-          bits: 64
-          vg: 'OFF'
-          img: 18.04
+          cxx: g++-14
+          bt: tsan
+          bitlinks: static64
+        - std: 14
+          cxx: g++-14
+          bt: tsan
+          bitlinks: static64
+        - std: 17
+          cxx: g++-14
+          bt: tsan
+          bitlinks: static64
+        - std: 20
+          cxx: g++-14
+          bt: tsan
+          bitlinks: static64
         - std: 11
-          cxx: 4.8
-          bits: 32
-          vg: 'OFF'
-          img: 18.04
+          cxx: g++-14
+          bt: ubsan
+          bitlinks: static64
+        - std: 14
+          cxx: g++-14
+          bt: ubsan
+          bitlinks: static64
+        - std: 17
+          cxx: g++-14
+          bt: ubsan
+          bitlinks: static64
+        - std: 20
+          cxx: g++-14
+          bt: ubsan
+          bitlinks: static64
     env:
       STD: ${{matrix.std}}
       CXX_: ${{matrix.cxx}}
@@ -1003,41 +822,141 @@ jobs:
       LINT: ${{matrix.lint}}
       OS: ${{matrix.os}}
     steps:
-    - name: checkout (manually)
-      run: |
-        set -xeo pipefail
-        env | sort
-        echo GITHUB_SERVER_URL=$GITHUB_SERVER_URL
-        echo GITHUB_REPOSITORY=$GITHUB_REPOSITORY
-        echo GITHUB_REF=$GITHUB_REF
-        echo GITHUB_REF_NAME=$GITHUB_REF_NAME
-        echo GITHUB_HEAD_REF=$GITHUB_HEAD_REF
-        repo=$GITHUB_SERVER_URL/$GITHUB_REPOSITORY
-        # check the branch
-        # https://stackoverflow.com/questions/58033366
-        branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
-        echo branch=$branch
-        # does the branch exist in the repo?
-        if [ -z "$(git ls-remote $repo | grep $branch)" ] ; then
-            echo "branch $branch does not exist on $repo"
-            # refs/pull/485/merge -> pull/485/head
-            branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
-            echo "... falling back to $branch"
-            # does the fallback exist?
-            if [ -z "(git ls-remote $repo | grep $branch)" ] ; then
-                echo "branch $branch does not exist on $repo"
-                exit 1
-            else
-                echo "branch $branch exists on $repo"
-                localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
-                branch=$branch:$localbranch
-                echo "naming locally as $branch"
-            fi
-        fi
-        # finally, create the local repo
-        git init -q .
-        # needed for running in the docker image.
-        # see https://github.com/actions/checkout/issues/1169
+    - name: checkout (action + docker)
+      uses: actions/checkout@v4
+      with:
+        submodules: recursive
+        fetch-depth: 0
+    - run: git config --system --add safe.directory '*'
+    - run: c4core-install ${{matrix.cxx}}
+    - name: show info
+      run: source .github/setenv.sh && c4_show_info
+    - name: shared64-configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test shared64
+    - name: shared64-build
+      run: source .github/setenv.sh && c4_build_test shared64
+    - name: shared64-run
+      run: source .github/setenv.sh && c4_run_test shared64
+    - name: shared64-pack
+      run: source .github/setenv.sh && c4_package shared64
+    - name: static64-configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test static64
+    - name: static64-build
+      run: source .github/setenv.sh && c4_build_test static64
+    - name: static64-run
+      run: source .github/setenv.sh && c4_run_test static64
+    - name: static64-pack
+      run: source .github/setenv.sh && c4_package static64
+    - name: static32-configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test static32
+    - name: static32-build
+      run: source .github/setenv.sh && c4_build_test static32
+    - name: static32-run
+      run: source .github/setenv.sh && c4_run_test static32
+    - name: static32-pack
+      run: source .github/setenv.sh && c4_package static32
+    - name: shared32-configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test shared32
+    - name: shared32-build
+      run: source .github/setenv.sh && c4_build_test shared32
+    - name: shared32-run
+      run: source .github/setenv.sh && c4_run_test shared32
+    - name: shared32-pack
+      run: source .github/setenv.sh && c4_package shared32
+    name: gccsan/${{matrix.bt}}/${{matrix.cxx}}/c++${{matrix.std}}
+  arm:
+    if: always()
+    continue-on-error: false
+    runs-on: ubuntu-24.04
+    container: ghcr.io/biojppm/c4core/ubuntu18.04:latest
+    name: arm/c++${{matrix.std}}/${{matrix.bt}}
+    needs: canary
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+        - std: 11
+          bt: Debug
+          cxx: arm-linux-gnueabihf-gcc
+          toolchain: ext/c4core/cmake/Toolchain-Arm-ubuntu.cmake
+        - std: 11
+          bt: Release
+          cxx: arm-linux-gnueabihf-gcc
+          toolchain: ext/c4core/cmake/Toolchain-Arm-ubuntu.cmake
+        - std: 14
+          bt: Debug
+          cxx: arm-linux-gnueabihf-gcc
+          toolchain: ext/c4core/cmake/Toolchain-Arm-ubuntu.cmake
+        - std: 14
+          bt: Release
+          cxx: arm-linux-gnueabihf-gcc
+          toolchain: ext/c4core/cmake/Toolchain-Arm-ubuntu.cmake
+        - std: 17
+          bt: Debug
+          cxx: arm-linux-gnueabihf-gcc
+          toolchain: ext/c4core/cmake/Toolchain-Arm-ubuntu.cmake
+        - std: 17
+          bt: Release
+          cxx: arm-linux-gnueabihf-gcc
+          toolchain: ext/c4core/cmake/Toolchain-Arm-ubuntu.cmake
+    env:
+      TOOLCHAIN: ${{matrix.toolchain}}
+      STD: ${{matrix.std}}
+      CXX_: ${{matrix.cxx}}
+      BT: ${{matrix.bt}}
+      BITLINKS: ${{matrix.bitlinks}}
+      VG: ${{matrix.vg}}
+      SAN: ${{matrix.san}}
+      LINT: ${{matrix.lint}}
+      OS: ${{matrix.os}}
+    steps:
+    - name: checkout (manually)
+      run: |
+        set -xeo pipefail
+        env | sort
+        echo GITHUB_SERVER_URL=$GITHUB_SERVER_URL
+        echo GITHUB_REPOSITORY=$GITHUB_REPOSITORY
+        echo GITHUB_REF=$GITHUB_REF
+        echo GITHUB_REF_NAME=$GITHUB_REF_NAME
+        echo GITHUB_HEAD_REF=$GITHUB_HEAD_REF
+        repo=$GITHUB_SERVER_URL/$GITHUB_REPOSITORY
+        # check the branch
+        # https://stackoverflow.com/questions/58033366
+        branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
+        echo branch=$branch
+        localbranch=$branch
+        rembranch=$branch
+        # does the branch exist in the repo?
+        if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
+            echo "branch $branch does not exist on $repo"
+            # refs/pull/485/merge -> pull/485/head
+            branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
+            localbranch=$branch
+            rembranch=$branch
+            echo "... falling back to $branch"
+            # does the fallback exist?
+            if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
+                echo "branch $branch does not exist on $repo"
+                exit 1
+            else
+                echo "branch $branch exists on $repo"
+                localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
+                echo "naming locally as $localbranch"
+                rembranch=$branch
+                branch=$branch:$localbranch
+            fi
+        fi
+        hash=$(git ls-remote $repo | grep -F $rembranch | awk '{print $1}')
+        echo "final repo=$repo"
+        echo "final branch=$branch"
+        echo "final rembranch=$rembranch"
+        echo "final localbranch=$localbranch"
+        echo "final hash=$hash"
+
+        # finally, create the local repo
+        git init -q .
+        # needed for running in the docker image.
+        # see https://github.com/actions/checkout/issues/1169
         git config --system --add safe.directory '*'
         # finally, do it!
         git remote add origin $repo
@@ -1051,223 +970,223 @@ jobs:
             || echo -n
         # show the last commit
         git log --name-status HEAD^..HEAD
-    - name: install
-      run: c4core-install g++-${{matrix.cxx}}
-    - name: '---------------------------------------------------------'
-      run: |
-        echo "Debug ::: -m${{matrix.bits}}"
-    - name: 'configure Debug ::: -m${{matrix.bits}}'
-      run: |
-        rm -rf build/Debug
-        export C4_EXTERN_DIR=`pwd`/build/extern
-        cmake -S . -B build/Debug \
-          -DCMAKE_CXX_COMPILER=g++-${{matrix.cxx}} \
-          -DCMAKE_C_COMPILER=gcc-${{matrix.cxx}} \
-          -DCMAKE_BUILD_TYPE=Debug \
-          -DCMAKE_CXX_FLAGS_DEBUG="-m${{matrix.bits}}" \
-          -DCMAKE_C_FLAGS_DEBUG="-m${{matrix.bits}}" \
-          -DC4_CXX_STANDARD=${{matrix.std}} \
-          -DRYML_CXX_STANDARD=${{matrix.std}} \
-          -DRYML_BUILD_TESTS=ON \
-          -DRYML_VALGRIND=${{matrix.vg}} \
-          -DRYML_DEV=ON \
-          -DRYML_BUILD_BENCHMARKS=OFF \
-          -DRYML_DBG=OFF
-    - name: 'build Debug ::: -m${{matrix.bits}}'
-      run: |
-        cmake --build build/Debug --target ryml-test-build --parallel --verbose
-    - name: 'run Debug ::: -m${{matrix.bits}}'
-      run: |
-        source .github/setenv.sh
-        export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
-        cmake --build build/Debug --target ryml-test-run
-    - name: '---------------------------------------------------------'
-      run: |
-        echo "Release ::: -O1 -DNDEBUG -m${{matrix.bits}}"
-    - name: 'configure Release ::: -O1 -DNDEBUG -m${{matrix.bits}}'
-      run: |
-        rm -rf build/Release
-        export C4_EXTERN_DIR=`pwd`/build/extern
-        cmake -S . -B build/Release \
-          -DCMAKE_CXX_COMPILER=g++-${{matrix.cxx}} \
-          -DCMAKE_C_COMPILER=gcc-${{matrix.cxx}} \
-          -DCMAKE_BUILD_TYPE=Release \
-          -DCMAKE_CXX_FLAGS_RELEASE="-O1 -DNDEBUG -m${{matrix.bits}}" \
-          -DCMAKE_C_FLAGS_RELEASE="-O1 -DNDEBUG -m${{matrix.bits}}" \
-          -DC4_CXX_STANDARD=${{matrix.std}} \
-          -DRYML_CXX_STANDARD=${{matrix.std}} \
-          -DRYML_BUILD_TESTS=ON \
-          -DRYML_VALGRIND=${{matrix.vg}} \
-          -DRYML_DEV=ON \
-          -DRYML_BUILD_BENCHMARKS=OFF \
-          -DRYML_DBG=OFF
-    - name: 'build Release ::: -O1 -DNDEBUG -m${{matrix.bits}}'
-      run: |
-        cmake --build build/Release --target ryml-test-build --parallel --verbose
-    - name: 'run Release ::: -O1 -DNDEBUG -m${{matrix.bits}}'
-      run: |
-        source .github/setenv.sh
-        export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
-        cmake --build build/Release --target ryml-test-run
-    - name: '---------------------------------------------------------'
-      run: |
-        echo "Release ::: -O2 -DNDEBUG -m${{matrix.bits}}"
-    - name: 'configure Release ::: -O2 -DNDEBUG -m${{matrix.bits}}'
-      run: |
-        rm -rf build/Release
-        export C4_EXTERN_DIR=`pwd`/build/extern
-        cmake -S . -B build/Release \
-          -DCMAKE_CXX_COMPILER=g++-${{matrix.cxx}} \
-          -DCMAKE_C_COMPILER=gcc-${{matrix.cxx}} \
-          -DCMAKE_BUILD_TYPE=Release \
-          -DCMAKE_CXX_FLAGS_RELEASE="-O2 -DNDEBUG -m${{matrix.bits}}" \
-          -DCMAKE_C_FLAGS_RELEASE="-O2 -DNDEBUG -m${{matrix.bits}}" \
-          -DC4_CXX_STANDARD=${{matrix.std}} \
-          -DRYML_CXX_STANDARD=${{matrix.std}} \
-          -DRYML_BUILD_TESTS=ON \
-          -DRYML_VALGRIND=${{matrix.vg}} \
-          -DRYML_DEV=ON \
-          -DRYML_BUILD_BENCHMARKS=OFF \
-          -DRYML_DBG=OFF
-    - name: 'build Release ::: -O2 -DNDEBUG -m${{matrix.bits}}'
-      run: |
-        cmake --build build/Release --target ryml-test-build --parallel --verbose
-    - name: 'run Release ::: -O2 -DNDEBUG -m${{matrix.bits}}'
-      run: |
-        source .github/setenv.sh
-        export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
-        cmake --build build/Release --target ryml-test-run
-    - name: '---------------------------------------------------------'
-      run: |
-        echo "Release ::: -O3 -DNDEBUG -m${{matrix.bits}}"
-    - name: 'configure Release ::: -O3 -DNDEBUG -m${{matrix.bits}}'
-      run: |
-        rm -rf build/Release
-        export C4_EXTERN_DIR=`pwd`/build/extern
-        cmake -S . -B build/Release \
-          -DCMAKE_CXX_COMPILER=g++-${{matrix.cxx}} \
-          -DCMAKE_C_COMPILER=gcc-${{matrix.cxx}} \
-          -DCMAKE_BUILD_TYPE=Release \
-          -DCMAKE_CXX_FLAGS_RELEASE="-O3 -DNDEBUG -m${{matrix.bits}}" \
-          -DCMAKE_C_FLAGS_RELEASE="-O3 -DNDEBUG -m${{matrix.bits}}" \
-          -DC4_CXX_STANDARD=${{matrix.std}} \
-          -DRYML_CXX_STANDARD=${{matrix.std}} \
-          -DRYML_BUILD_TESTS=ON \
-          -DRYML_VALGRIND=${{matrix.vg}} \
-          -DRYML_DEV=ON \
-          -DRYML_BUILD_BENCHMARKS=OFF \
-          -DRYML_DBG=OFF
-    - name: 'build Release ::: -O3 -DNDEBUG -m${{matrix.bits}}'
-      run: |
-        cmake --build build/Release --target ryml-test-build --parallel --verbose
-    - name: 'run Release ::: -O3 -DNDEBUG -m${{matrix.bits}}'
-      run: |
-        source .github/setenv.sh
-        export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
-        cmake --build build/Release --target ryml-test-run
-    - name: '---------------------------------------------------------'
-      run: |
-        echo "Release ::: -Os -DNDEBUG -m${{matrix.bits}}"
-    - name: 'configure Release ::: -Os -DNDEBUG -m${{matrix.bits}}'
-      run: |
-        rm -rf build/Release
-        export C4_EXTERN_DIR=`pwd`/build/extern
-        cmake -S . -B build/Release \
-          -DCMAKE_CXX_COMPILER=g++-${{matrix.cxx}} \
-          -DCMAKE_C_COMPILER=gcc-${{matrix.cxx}} \
-          -DCMAKE_BUILD_TYPE=Release \
-          -DCMAKE_CXX_FLAGS_RELEASE="-Os -DNDEBUG -m${{matrix.bits}}" \
-          -DCMAKE_C_FLAGS_RELEASE="-Os -DNDEBUG -m${{matrix.bits}}" \
-          -DC4_CXX_STANDARD=${{matrix.std}} \
-          -DRYML_CXX_STANDARD=${{matrix.std}} \
-          -DRYML_BUILD_TESTS=ON \
-          -DRYML_VALGRIND=${{matrix.vg}} \
-          -DRYML_DEV=ON \
-          -DRYML_BUILD_BENCHMARKS=OFF \
-          -DRYML_DBG=OFF
-    - name: 'build Release ::: -Os -DNDEBUG -m${{matrix.bits}}'
-      run: |
-        cmake --build build/Release --target ryml-test-build --parallel --verbose
-    - name: 'run Release ::: -Os -DNDEBUG -m${{matrix.bits}}'
+    - name: install gcc-arm-linux-gnueabihf
+      run: c4core-install arm-linux-gnueabihf; c4core-install qemu
+    - name: show info
+      run: source .github/setenv.sh && c4_show_info
+    - name: configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test arm
+    - name: build
+      run: source .github/setenv.sh && c4_build_test arm
+    - name: run
+      run: source .github/setenv.sh && c4_run_test arm
+    - name: pack
+      run: source .github/setenv.sh && c4_package arm
+  canary:
+    if: always()
+    continue-on-error: false
+    runs-on: ubuntu-24.04
+    container: ghcr.io/biojppm/c4core/ubuntu${{matrix.img}}:latest
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+        - std: 11
+          cxx: g++-13
+          bt: Debug
+          bitlinks: shared64 static32
+          img: '22.04'
+        - std: 11
+          cxx: g++-13
+          bt: Release
+          bitlinks: shared64 static32
+          img: '22.04'
+        - std: 20
+          cxx: g++-13
+          bt: Debug
+          bitlinks: shared64 static32
+          img: '22.04'
+        - std: 20
+          cxx: g++-13
+          bt: Release
+          bitlinks: shared64 static32
+          img: '22.04'
+        - std: 11
+          cxx: g++-5
+          bt: Debug
+          bitlinks: shared64 static32
+          img: '18.04'
+        - std: 11
+          cxx: g++-5
+          bt: Release
+          bitlinks: shared64 static32
+          img: '18.04'
+        - std: 11
+          cxx: g++-4.8
+          bt: Debug
+          bitlinks: shared64 static32
+          img: '18.04'
+        - std: 11
+          cxx: g++-4.8
+          bt: Release
+          bitlinks: shared64 static32
+          img: '18.04'
+    env:
+      STD: ${{matrix.std}}
+      CXX_: ${{matrix.cxx}}
+      BT: ${{matrix.bt}}
+      BITLINKS: ${{matrix.bitlinks}}
+      VG: ${{matrix.vg}}
+      SAN: ${{matrix.san}}
+      LINT: ${{matrix.lint}}
+      OS: ${{matrix.os}}
+    steps:
+    - name: checkout (manually)
       run: |
-        source .github/setenv.sh
-        export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
-        cmake --build build/Release --target ryml-test-run
-  gccsan:
+        set -xeo pipefail
+        env | sort
+        echo GITHUB_SERVER_URL=$GITHUB_SERVER_URL
+        echo GITHUB_REPOSITORY=$GITHUB_REPOSITORY
+        echo GITHUB_REF=$GITHUB_REF
+        echo GITHUB_REF_NAME=$GITHUB_REF_NAME
+        echo GITHUB_HEAD_REF=$GITHUB_HEAD_REF
+        repo=$GITHUB_SERVER_URL/$GITHUB_REPOSITORY
+        # check the branch
+        # https://stackoverflow.com/questions/58033366
+        branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
+        echo branch=$branch
+        localbranch=$branch
+        rembranch=$branch
+        # does the branch exist in the repo?
+        if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
+            echo "branch $branch does not exist on $repo"
+            # refs/pull/485/merge -> pull/485/head
+            branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
+            localbranch=$branch
+            rembranch=$branch
+            echo "... falling back to $branch"
+            # does the fallback exist?
+            if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
+                echo "branch $branch does not exist on $repo"
+                exit 1
+            else
+                echo "branch $branch exists on $repo"
+                localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
+                echo "naming locally as $localbranch"
+                rembranch=$branch
+                branch=$branch:$localbranch
+            fi
+        fi
+        hash=$(git ls-remote $repo | grep -F $rembranch | awk '{print $1}')
+        echo "final repo=$repo"
+        echo "final branch=$branch"
+        echo "final rembranch=$rembranch"
+        echo "final localbranch=$localbranch"
+        echo "final hash=$hash"
+
+        # finally, create the local repo
+        git init -q .
+        # needed for running in the docker image.
+        # see https://github.com/actions/checkout/issues/1169
+        git config --system --add safe.directory '*'
+        # finally, do it!
+        git remote add origin $repo
+        git fetch origin $branch
+        git reset --hard FETCH_HEAD
+        git submodule update --init --recursive
+        # show the log
+        git log --graph --date=relative --date-order --color=always \
+                --pretty='%C(yellow)%h %C(cyan)%cd %Cblue%aN%C(auto)%d %Creset%s' \
+            | head -30 \
+            || echo -n
+        # show the last commit
+        git log --name-status HEAD^..HEAD
+    - run: c4core-install ${{matrix.cxx}}
+    - name: show info
+      run: source .github/setenv.sh && c4_show_info
+    - name: shared64-configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test shared64
+    - name: shared64-build
+      run: source .github/setenv.sh && c4_build_test shared64
+    - name: shared64-run
+      run: source .github/setenv.sh && c4_run_test shared64
+    - name: shared64-pack
+      run: source .github/setenv.sh && c4_package shared64
+    - name: static64-configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test static64
+    - name: static64-build
+      run: source .github/setenv.sh && c4_build_test static64
+    - name: static64-run
+      run: source .github/setenv.sh && c4_run_test static64
+    - name: static64-pack
+      run: source .github/setenv.sh && c4_package static64
+    - name: static32-configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test static32
+    - name: static32-build
+      run: source .github/setenv.sh && c4_build_test static32
+    - name: static32-run
+      run: source .github/setenv.sh && c4_run_test static32
+    - name: static32-pack
+      run: source .github/setenv.sh && c4_package static32
+    - name: shared32-configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test shared32
+    - name: shared32-build
+      run: source .github/setenv.sh && c4_build_test shared32
+    - name: shared32-run
+      run: source .github/setenv.sh && c4_run_test shared32
+    - name: shared32-pack
+      run: source .github/setenv.sh && c4_package shared32
+    name: canary/${{matrix.cxx}}/c++${{matrix.std}}/${{matrix.bt}}
+  tabtokens:
     if: always()
     continue-on-error: false
-    name: gccsan/${{matrix.bt}}/${{matrix.cxx}}/c++${{matrix.std}}
     runs-on: ubuntu-24.04
-    container: ghcr.io/biojppm/c4core/ubuntu22.04:latest
+    container: ghcr.io/biojppm/c4core/ubuntu${{matrix.img}}:latest
     needs: canary
     strategy:
       fail-fast: false
       matrix:
         include:
         - std: 11
-          cxx: g++-14
-          bt: asan
-          bitlinks: static64
-        - std: 14
-          cxx: g++-14
-          bt: asan
-          bitlinks: static64
-        - std: 17
-          cxx: g++-14
-          bt: asan
-          bitlinks: static64
-        - std: 20
-          cxx: g++-14
-          bt: asan
-          bitlinks: static64
+          cxx: g++-13
+          bt: Debug
+          bitlinks: shared64 static32
+          img: '22.04'
         - std: 11
-          cxx: g++-14
-          bt: lsan
-          bitlinks: static64
-        - std: 14
-          cxx: g++-14
-          bt: lsan
-          bitlinks: static64
-        - std: 17
-          cxx: g++-14
-          bt: lsan
-          bitlinks: static64
+          cxx: g++-13
+          bt: Release
+          bitlinks: shared64 static32
+          img: '22.04'
         - std: 20
-          cxx: g++-14
-          bt: lsan
-          bitlinks: static64
-        - std: 11
-          cxx: g++-14
-          bt: tsan
-          bitlinks: static64
-        - std: 14
-          cxx: g++-14
-          bt: tsan
-          bitlinks: static64
-        - std: 17
-          cxx: g++-14
-          bt: tsan
-          bitlinks: static64
+          cxx: g++-13
+          bt: Debug
+          bitlinks: shared64 static32
+          img: '22.04'
         - std: 20
-          cxx: g++-14
-          bt: tsan
-          bitlinks: static64
+          cxx: g++-13
+          bt: Release
+          bitlinks: shared64 static32
+          img: '22.04'
         - std: 11
-          cxx: g++-14
-          bt: ubsan
-          bitlinks: static64
-        - std: 14
-          cxx: g++-14
-          bt: ubsan
-          bitlinks: static64
-        - std: 17
-          cxx: g++-14
-          bt: ubsan
-          bitlinks: static64
-        - std: 20
-          cxx: g++-14
-          bt: ubsan
-          bitlinks: static64
+          cxx: g++-5
+          bt: Debug
+          bitlinks: shared64 static32
+          img: '18.04'
+        - std: 11
+          cxx: g++-5
+          bt: Release
+          bitlinks: shared64 static32
+          img: '18.04'
+        - std: 11
+          cxx: g++-4.8
+          bt: Debug
+          bitlinks: shared64 static32
+          img: '18.04'
+        - std: 11
+          cxx: g++-4.8
+          bt: Release
+          bitlinks: shared64 static32
+          img: '18.04'
     env:
       STD: ${{matrix.std}}
       CXX_: ${{matrix.cxx}}
@@ -1277,13 +1196,68 @@ jobs:
       SAN: ${{matrix.san}}
       LINT: ${{matrix.lint}}
       OS: ${{matrix.os}}
+      CMAKE_FLAGS: -DRYML_WITH_TAB_TOKENS=ON
     steps:
-    - name: checkout (action + docker)
-      uses: actions/checkout@v4
-      with:
-        submodules: recursive
-        fetch-depth: 0
-    - run: git config --system --add safe.directory '*'
+    - name: checkout (manually)
+      run: |
+        set -xeo pipefail
+        env | sort
+        echo GITHUB_SERVER_URL=$GITHUB_SERVER_URL
+        echo GITHUB_REPOSITORY=$GITHUB_REPOSITORY
+        echo GITHUB_REF=$GITHUB_REF
+        echo GITHUB_REF_NAME=$GITHUB_REF_NAME
+        echo GITHUB_HEAD_REF=$GITHUB_HEAD_REF
+        repo=$GITHUB_SERVER_URL/$GITHUB_REPOSITORY
+        # check the branch
+        # https://stackoverflow.com/questions/58033366
+        branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
+        echo branch=$branch
+        localbranch=$branch
+        rembranch=$branch
+        # does the branch exist in the repo?
+        if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
+            echo "branch $branch does not exist on $repo"
+            # refs/pull/485/merge -> pull/485/head
+            branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
+            localbranch=$branch
+            rembranch=$branch
+            echo "... falling back to $branch"
+            # does the fallback exist?
+            if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
+                echo "branch $branch does not exist on $repo"
+                exit 1
+            else
+                echo "branch $branch exists on $repo"
+                localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
+                echo "naming locally as $localbranch"
+                rembranch=$branch
+                branch=$branch:$localbranch
+            fi
+        fi
+        hash=$(git ls-remote $repo | grep -F $rembranch | awk '{print $1}')
+        echo "final repo=$repo"
+        echo "final branch=$branch"
+        echo "final rembranch=$rembranch"
+        echo "final localbranch=$localbranch"
+        echo "final hash=$hash"
+
+        # finally, create the local repo
+        git init -q .
+        # needed for running in the docker image.
+        # see https://github.com/actions/checkout/issues/1169
+        git config --system --add safe.directory '*'
+        # finally, do it!
+        git remote add origin $repo
+        git fetch origin $branch
+        git reset --hard FETCH_HEAD
+        git submodule update --init --recursive
+        # show the log
+        git log --graph --date=relative --date-order --color=always \
+                --pretty='%C(yellow)%h %C(cyan)%cd %Cblue%aN%C(auto)%d %Creset%s' \
+            | head -30 \
+            || echo -n
+        # show the last commit
+        git log --name-status HEAD^..HEAD
     - run: c4core-install ${{matrix.cxx}}
     - name: show info
       run: source .github/setenv.sh && c4_show_info
@@ -1319,43 +1293,58 @@ jobs:
       run: source .github/setenv.sh && c4_run_test shared32
     - name: shared32-pack
       run: source .github/setenv.sh && c4_package shared32
-  arm:
+    name: tabtokens/${{matrix.cxx}}/c++${{matrix.std}}/${{matrix.bt}}
+  noexceptions:
     if: always()
     continue-on-error: false
     runs-on: ubuntu-24.04
-    container: ghcr.io/biojppm/c4core/ubuntu18.04:latest
-    name: arm/c++${{matrix.std}}/${{matrix.bt}}
+    container: ghcr.io/biojppm/c4core/ubuntu${{matrix.img}}:latest
     needs: canary
     strategy:
       fail-fast: false
       matrix:
         include:
         - std: 11
+          cxx: g++-13
           bt: Debug
-          cxx: arm-linux-gnueabihf-gcc
-          toolchain: ext/c4core/cmake/Toolchain-Arm-ubuntu.cmake
+          bitlinks: shared64 static32
+          img: '22.04'
         - std: 11
+          cxx: g++-13
           bt: Release
-          cxx: arm-linux-gnueabihf-gcc
-          toolchain: ext/c4core/cmake/Toolchain-Arm-ubuntu.cmake
-        - std: 14
+          bitlinks: shared64 static32
+          img: '22.04'
+        - std: 20
+          cxx: g++-13
           bt: Debug
-          cxx: arm-linux-gnueabihf-gcc
-          toolchain: ext/c4core/cmake/Toolchain-Arm-ubuntu.cmake
-        - std: 14
+          bitlinks: shared64 static32
+          img: '22.04'
+        - std: 20
+          cxx: g++-13
           bt: Release
-          cxx: arm-linux-gnueabihf-gcc
-          toolchain: ext/c4core/cmake/Toolchain-Arm-ubuntu.cmake
-        - std: 17
+          bitlinks: shared64 static32
+          img: '22.04'
+        - std: 11
+          cxx: g++-5
           bt: Debug
-          cxx: arm-linux-gnueabihf-gcc
-          toolchain: ext/c4core/cmake/Toolchain-Arm-ubuntu.cmake
-        - std: 17
+          bitlinks: shared64 static32
+          img: '18.04'
+        - std: 11
+          cxx: g++-5
           bt: Release
-          cxx: arm-linux-gnueabihf-gcc
-          toolchain: ext/c4core/cmake/Toolchain-Arm-ubuntu.cmake
+          bitlinks: shared64 static32
+          img: '18.04'
+        - std: 11
+          cxx: g++-4.8
+          bt: Debug
+          bitlinks: shared64 static32
+          img: '18.04'
+        - std: 11
+          cxx: g++-4.8
+          bt: Release
+          bitlinks: shared64 static32
+          img: '18.04'
     env:
-      TOOLCHAIN: ${{matrix.toolchain}}
       STD: ${{matrix.std}}
       CXX_: ${{matrix.cxx}}
       BT: ${{matrix.bt}}
@@ -1364,6 +1353,7 @@ jobs:
       SAN: ${{matrix.san}}
       LINT: ${{matrix.lint}}
       OS: ${{matrix.os}}
+      CXXFLAGS: -fno-exceptions -fno-rtti
     steps:
     - name: checkout (manually)
       run: |
@@ -1379,23 +1369,35 @@ jobs:
         # https://stackoverflow.com/questions/58033366
         branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
         echo branch=$branch
+        localbranch=$branch
+        rembranch=$branch
         # does the branch exist in the repo?
-        if [ -z "$(git ls-remote $repo | grep $branch)" ] ; then
+        if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
             echo "branch $branch does not exist on $repo"
             # refs/pull/485/merge -> pull/485/head
             branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
+            localbranch=$branch
+            rembranch=$branch
             echo "... falling back to $branch"
             # does the fallback exist?
-            if [ -z "(git ls-remote $repo | grep $branch)" ] ; then
+            if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
                 echo "branch $branch does not exist on $repo"
                 exit 1
             else
                 echo "branch $branch exists on $repo"
                 localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
+                echo "naming locally as $localbranch"
+                rembranch=$branch
                 branch=$branch:$localbranch
-                echo "naming locally as $branch"
             fi
         fi
+        hash=$(git ls-remote $repo | grep -F $rembranch | awk '{print $1}')
+        echo "final repo=$repo"
+        echo "final branch=$branch"
+        echo "final rembranch=$rembranch"
+        echo "final localbranch=$localbranch"
+        echo "final hash=$hash"
+
         # finally, create the local repo
         git init -q .
         # needed for running in the docker image.
@@ -1413,15 +1415,97 @@ jobs:
             || echo -n
         # show the last commit
         git log --name-status HEAD^..HEAD
-    - name: install gcc-arm-linux-gnueabihf
-      run: c4core-install arm-linux-gnueabihf; c4core-install qemu
+    - run: c4core-install ${{matrix.cxx}}
     - name: show info
       run: source .github/setenv.sh && c4_show_info
-    - name: configure---------------------------------------------------
-      run: source .github/setenv.sh && c4_cfg_test arm
-    - name: build
-      run: source .github/setenv.sh && c4_build_test arm
-    - name: run
-      run: source .github/setenv.sh && c4_run_test arm
-    - name: pack
-      run: source .github/setenv.sh && c4_package arm
+    - name: shared64-configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test shared64
+    - name: shared64-build
+      run: source .github/setenv.sh && c4_build_test shared64
+    - name: shared64-run
+      run: source .github/setenv.sh && c4_run_test shared64
+    - name: shared64-pack
+      run: source .github/setenv.sh && c4_package shared64
+    - name: static64-configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test static64
+    - name: static64-build
+      run: source .github/setenv.sh && c4_build_test static64
+    - name: static64-run
+      run: source .github/setenv.sh && c4_run_test static64
+    - name: static64-pack
+      run: source .github/setenv.sh && c4_package static64
+    - name: static32-configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test static32
+    - name: static32-build
+      run: source .github/setenv.sh && c4_build_test static32
+    - name: static32-run
+      run: source .github/setenv.sh && c4_run_test static32
+    - name: static32-pack
+      run: source .github/setenv.sh && c4_package static32
+    - name: shared32-configure---------------------------------------------------
+      run: source .github/setenv.sh && c4_cfg_test shared32
+    - name: shared32-build
+      run: source .github/setenv.sh && c4_build_test shared32
+    - name: shared32-run
+      run: source .github/setenv.sh && c4_run_test shared32
+    - name: shared32-pack
+      run: source .github/setenv.sh && c4_package shared32
+    name: noexceptions/${{matrix.cxx}}/c++${{matrix.std}}/${{matrix.bt}}
+  misbuild:
+    if: always()
+    continue-on-error: false
+    runs-on: ubuntu-24.04
+    container: ghcr.io/biojppm/c4core/ubuntu${{matrix.img}}:latest
+    needs: canary
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+        - issue: 440
+          std: 11
+          gcc: 12
+          bt: Release
+          img: 22.04
+          cxxflags: -O2 -DNDEBUG -g
+        - issue: 486
+          std: 11
+          gcc: 11
+          bt: Release
+          img: 22.04
+          cxxflags: -O3 -DNDEBUG
+    env:
+      STD: ${{matrix.std}}
+      CXX_: ${{matrix.gcc}}
+      BT: ${{matrix.bt}}
+      BITLINKS: ${{matrix.bitlinks}}
+      VG: ${{matrix.vg}}
+      SAN: ${{matrix.san}}
+      LINT: ${{matrix.lint}}
+      OS: ${{matrix.os}}
+    steps:
+    - name: checkout (action + docker)
+      uses: actions/checkout@v4
+      with:
+        submodules: recursive
+        fetch-depth: 0
+    - run: git config --system --add safe.directory '*'
+    - run: c4core-install g++-${{matrix.gcc}}
+    - name: show info
+      run: source .github/setenv.sh && c4_show_info
+    - name: configure (issue \#${{matrix.issue}})
+      run: |
+        cmake -S . -B build \
+          -DCMAKE_CXX_COMPILER=g++-${{matrix.gcc}} \
+          -DCMAKE_C_COMPILER=gcc-${{matrix.gcc}} \
+          -DCMAKE_BUILD_TYPE=Release \
+          -DCMAKE_CXX_FLAGS_RELEASE="${{matrix.cxxflags}}" \
+          -DRYML_BUILD_TESTS=ON \
+          -DRYML_DBG=OFF
+    - name: build (issue \#${{matrix.issue}})
+      run: cmake --build build --target ryml-test-build --parallel --verbose
+    - name: run (issue \#${{matrix.issue}})
+      run: |
+        source .github/setenv.sh
+        export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
+        cmake --build build --target ryml-test-run
+    name: misbuild#${{matrix.issue}}/gcc${{matrix.gcc}}/c++${{matrix.std}}
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 2462b46f8..08cafa945 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -239,7 +239,7 @@ jobs:
         mkdir -p assets
         asset_src=`ls -1 ./build/shared64/*-${{matrix.config.sfxg}}`
         asset_dst=./assets/${PROJ_PKG_NAME}${SRC_VERSION}-${{matrix.config.sfxp}}
-        [ ! -f $asset_src ] && exit 1
+        [ -f $asset_src ] || exit
         cp -fav $asset_src $asset_dst
     - name: Save artifacts
       uses: actions/upload-artifact@v4
diff --git a/.github/workflows/samples.yml b/.github/workflows/samples.yml
index 33123d3fa..60f740de0 100644
--- a/.github/workflows/samples.yml
+++ b/.github/workflows/samples.yml
@@ -83,13 +83,47 @@ jobs:
       run: cd samples/custom_c4core && ./run.sh $BT
     - name: fetch_content
       run: |
-        # run this sample only if the branch exists on the repo
-        set -xe
+        set -xeo pipefail
         cd samples/fetch_content
+        env | sort
+        echo GITHUB_SERVER_URL=$GITHUB_SERVER_URL
+        echo GITHUB_REPOSITORY=$GITHUB_REPOSITORY
+        echo GITHUB_REF=$GITHUB_REF
+        echo GITHUB_REF_NAME=$GITHUB_REF_NAME
+        echo GITHUB_HEAD_REF=$GITHUB_HEAD_REF
         repo=$GITHUB_SERVER_URL/$GITHUB_REPOSITORY
+        # check the branch
         # https://stackoverflow.com/questions/58033366
         branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
         echo branch=$branch
-        if [ ! -z "$(git ls-remote $repo | grep $branch)" ] ; then
-           ./run.sh $BT $branch "$repo"
+        localbranch=$branch
+        rembranch=$branch
+        # does the branch exist in the repo?
+        if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
+            echo "branch $branch does not exist on $repo"
+            # refs/pull/485/merge -> pull/485/head
+            branch=`echo ${GITHUB_REF#refs/} | sed -e 's:merge:head:g'`
+            localbranch=$branch
+            rembranch=$branch
+            echo "... falling back to $branch"
+            # does the fallback exist?
+            if [ -z "$(git ls-remote $repo | grep -F $branch)" ] ; then
+                echo "branch $branch does not exist on $repo"
+                exit 1
+            else
+                echo "branch $branch exists on $repo"
+                localbranch=$(echo $branch | sed -e 's@[/:]@_@g')
+                echo "naming locally as $localbranch"
+                rembranch=$branch
+                branch=$branch:$localbranch
+            fi
         fi
+        hash=$(git ls-remote $repo | grep -F $rembranch | awk '{print $1}')
+        echo "final repo=$repo"
+        echo "final branch=$branch"
+        echo "final rembranch=$rembranch"
+        echo "final localbranch=$localbranch"
+        echo "final hash=$hash"
+
+        # run this sample only if the branch exists on the repo
+        ./run.sh $BT $hash "$repo" || echo 'maybe some other time'
diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index 3b0fe938d..82f04e924 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -22,7 +22,6 @@ jobs:
   vsdebug:
     if: always()
     continue-on-error: false
-    name: ${{matrix.name}}bit/c++${{matrix.std}}/debug
     runs-on: windows-${{matrix.os}}
     strategy:
       fail-fast: false
@@ -145,10 +144,10 @@ jobs:
         source .github/setenv.sh
         export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
         cmake --build build/Release --target ryml-test-run
+    name: ${{matrix.name}}bit/c++${{matrix.std}}/debug
   vsrelease:
     if: always()
     continue-on-error: false
-    name: ${{matrix.name}}bit/c++${{matrix.std}}/release
     runs-on: windows-${{matrix.os}}
     strategy:
       fail-fast: false
@@ -271,3 +270,4 @@ jobs:
         source .github/setenv.sh
         export CTEST_PARALLEL_LEVEL=`_c4getnumcores`
         cmake --build build/Release --target ryml-test-run
+    name: ${{matrix.name}}bit/c++${{matrix.std}}/release
diff --git a/samples/fetch_content/CMakeLists.txt b/samples/fetch_content/CMakeLists.txt
index 8f3499606..d24f6c8b9 100644
--- a/samples/fetch_content/CMakeLists.txt
+++ b/samples/fetch_content/CMakeLists.txt
@@ -2,14 +2,17 @@ cmake_minimum_required(VERSION 3.13 FATAL_ERROR)
 project(ryml-quickstart LANGUAGES CXX)
 
 set(RYML_REPO_URL https://github.com/biojppm/rapidyaml CACHE STRING "")
-set(RYML_BRANCH_NAME master CACHE STRING "")
+set(RYML_TAG_NAME master CACHE STRING "")
 message(STATUS "FetchContent from repo: ${RYML_REPO_URL}")
-message(STATUS "FetchContent from branch: ${RYML_BRANCH_NAME}")
+message(STATUS "FetchContent from tag: ${RYML_TAG_NAME}")
+
 include(FetchContent)
 FetchContent_Declare(ryml
     GIT_REPOSITORY ${RYML_REPO_URL}
-    GIT_TAG ${RYML_BRANCH_NAME}
-    GIT_SHALLOW FALSE  # ensure submodules are checked out
+    GIT_TAG ${RYML_TAG_NAME}
+    # Do not set GIT_SHALLOW: if enabled then GIT_TAG works only with
+    # branch names and tags, and a commit hash is not allowed.
+    GIT_SHALLOW FALSE
 )
 FetchContent_MakeAvailable(ryml)
 
diff --git a/samples/fetch_content/run.sh b/samples/fetch_content/run.sh
index 306471453..7933e0ae0 100755
--- a/samples/fetch_content/run.sh
+++ b/samples/fetch_content/run.sh
@@ -12,7 +12,7 @@ cd $(dirname $0)
 # configure the sample
 cmake -S . -B ./build/$cfg \
       -DCMAKE_BUILD_TYPE=$cfg \
-      -DRYML_BRANCH_NAME=$branch \
+      -DRYML_TAG_NAME=$branch \
       -DRYML_REPO_URL=$repo
 # build and run the sample
 cmake --build ./build/$cfg --config $cfg --target run