diff --git a/CHANGELOG.md b/CHANGELOG.md
index c324e490..60439235 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,17 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+- **Breaking: the Chrome companion moved behind the `chrome-extension`
+  feature.** `tinyflows::browser` and `tinyflows::companion` — previously part
+  of the default public API at `0.6.1` — now compile only when the
+  `chrome-extension` feature is enabled, and the `tinyflows` CLI binary requires
+  that feature too. The core engine no longer pulls in the `axum`/`reqwest`
+  listener and HTTP client stack by default. Downstream code that used
+  `tinyflows::browser` or `tinyflows::companion` must enable the feature (e.g.
+  `tinyflows = { version = "0.7", features = ["chrome-extension"] }`).
+  Correspondingly released as a major semver change (`0.7.0`, breaking in `0.x`
+  terms).
+
 - **Removed the `tinyagents` dependency.** The state-graph runtime the engine
   lowers workflows onto now lives in-crate as `crate::graph` (builder, superstep
   executor, channels, reducers, commands/interrupts, checkpointing, run status,
diff --git a/Cargo.lock b/Cargo.lock
index 6d092579..a26e8f5a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -8,15 +8,6 @@ version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "320119579fcad9c21884f5c4861d16174d0e06250625266f50fe6898340abefa"
 
-[[package]]
-name = "aho-corasick"
-version = "1.1.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ddd31a130427c27518df266943a5308ed92d4b226cc639f5a8f1002816174301"
-dependencies = [
- "memchr",
-]
-
 [[package]]
 name = "async-trait"
 version = "0.1.92"
@@ -40,6 +31,29 @@ version = "1.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f2032f911046de80f0a198e0901378627c33f59ea0ac00e363d481118bd70a53"
 
+[[package]]
+name = "aws-lc-rs"
+version = "1.18.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ce2b2dcc879c3bae0d371e77c99f2238400ef24ec001394befa67b6e543add9e"
+dependencies = [
+ "aws-lc-sys",
+ "zeroize",
+]
+
+[[package]]
+name = "aws-lc-sys"
+version = "0.44.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f09fae7be8bb3174e05c6afdb34199e6dc0c7c04ba9fa237b1967adfbde27483"
+dependencies = [
+ "cc",
+ "cmake",
+ "dunce",
+ "fs_extra",
+ "pkg-config",
+]
+
 [[package]]
 name = "axum"
 version = "0.8.9"
@@ -49,7 +63,6 @@ dependencies = [
  "axum-core",
  "base64",
  "bytes",
- "form_urlencoded",
  "futures-util",
  "http",
  "http-body",
@@ -65,7 +78,6 @@ dependencies = [
  "serde_core",
  "serde_json",
  "serde_path_to_error",
- "serde_urlencoded",
  "sha1",
  "sync_wrapper",
  "tokio",
@@ -73,7 +85,6 @@ dependencies = [
  "tower",
  "tower-layer",
  "tower-service",
- "tracing",
 ]
 
 [[package]]
@@ -92,7 +103,6 @@ dependencies = [
  "sync_wrapper",
  "tower-layer",
  "tower-service",
- "tracing",
 ]
 
 [[package]]
@@ -116,12 +126,6 @@ version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5e764a1d40d510daf35e07be9eb06e75770908c27d411ee6c92109c9840eaaf7"
 
-[[package]]
-name = "bitflags"
-version = "1.3.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
-
 [[package]]
 name = "bitflags"
 version = "2.13.0"
@@ -172,12 +176,76 @@ version = "1.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8ae3f5d315924270530207e2a68396c3cc547f6dca3fbdca317cfb1a51edb593"
 
+[[package]]
+name = "cc"
+version = "1.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5d262e149917187838d5b42777c8253bcb64500067342904e7d429499a6f277e"
+dependencies = [
+ "find-msvc-tools",
+ "jobserver",
+ "libc",
+ "shlex",
+]
+
 [[package]]
 name = "cfg-if"
 version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9330f8b2ff13f34540b44e946ef35111825727b38d33286ef986142615121801"
 
+[[package]]
+name = "cfg_aliases"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f079e83a288787bcd14a6aea84cee5c87a67c5a3e660c30f557a3d24761b3527"
+
+[[package]]
+name = "chacha20"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d524456ba66e72eb8b115ff89e01e497f8e6d11d78b70b1aa13c0fbd97540a81"
+dependencies = [
+ "cfg-if",
+ "cpufeatures 0.3.0",
+ "rand_core 0.10.1",
+]
+
+[[package]]
+name = "cmake"
+version = "0.1.58"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c0f78a02292a74a88ac736019ab962ece0bc380e3f977bf72e376c5d78ff0678"
+dependencies = [
+ "cc",
+]
+
+[[package]]
+name = "combine"
+version = "4.6.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba5a308b75df32fe02788e748662718f03fde005016435c444eea572398219fd"
+dependencies = [
+ "bytes",
+ "memchr",
+]
+
+[[package]]
+name = "core-foundation"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2a6cd9ae233e7f62ba4e9353e81a88df7fc8a5987b8d445b4d90c879bd156f6"
+dependencies = [
+ "core-foundation-sys",
+ "libc",
+]
+
+[[package]]
+name = "core-foundation-sys"
+version = "0.8.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "773648b94d0e5d620f64f280777445740e61fe701025087ec8b57f45c791888b"
+
 [[package]]
 name = "cpufeatures"
 version = "0.2.17"
@@ -187,6 +255,15 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "cpufeatures"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b2a41393f66f16b0823bb79094d54ac5fbd34ab292ddafb9a0456ac9f87d201"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "crc32fast"
 version = "1.5.0"
@@ -212,38 +289,6 @@ version = "2.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a4ae5f15dda3c708c0ade84bfee31ccab44a3da4f88015ed22f63732abe300c8"
 
-[[package]]
-name = "defmt"
-version = "1.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a6e524506490a1953d237cb87b1cfc1e46f88c18f10a22dfe0f507dc6bfc7f7f"
-dependencies = [
- "bitflags 1.3.2",
- "defmt-macros",
-]
-
-[[package]]
-name = "defmt-macros"
-version = "1.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f0a27770e9c8f719a79d8b638281f4d828f77d8fd61e0bd94451b9b85e576a0b"
-dependencies = [
- "defmt-parser",
- "proc-macro-error2",
- "proc-macro2",
- "quote",
- "syn 2.0.118",
-]
-
-[[package]]
-name = "defmt-parser"
-version = "1.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "10d60334b3b2e7c9d91ef8150abfb6fa4c1c39ebbcf4a81c2e346aad939fee3e"
-dependencies = [
- "thiserror",
-]
-
 [[package]]
 name = "digest"
 version = "0.10.7"
@@ -265,6 +310,12 @@ dependencies = [
  "syn 2.0.118",
 ]
 
+[[package]]
+name = "dunce"
+version = "1.0.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "92773504d58c093f6de2459af4af33faa518c13451eb8f2b5698ed3d36e7c813"
+
 [[package]]
 name = "dyn-clone"
 version = "1.0.20"
@@ -284,7 +335,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "39cab71617ae0d63f51a36d69f866391735b51691dbda63cf6f96d042b63efeb"
 dependencies = [
  "libc",
- "windows-sys",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]
@@ -302,6 +353,12 @@ dependencies = [
  "simd-adler32",
 ]
 
+[[package]]
+name = "find-msvc-tools"
+version = "0.1.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26b73573e6edcd2af0cdf47bd6cb58f0b3839491263c314eaad1ccf24430e1de"
+
 [[package]]
 name = "flate2"
 version = "1.1.9"
@@ -349,6 +406,12 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "fs_extra"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "42703706b716c37f96a77aea830392ad231f44c9e9a67872fa5548707e11b11c"
+
 [[package]]
 name = "futures-channel"
 version = "0.3.33"
@@ -364,17 +427,6 @@ version = "0.3.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2cd50c473c80f6d7c3670a752354b8e569b1a7cbfdc0419ec88e5edad85e0dc7"
 
-[[package]]
-name = "futures-macro"
-version = "0.3.33"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2d6d3cde68c518367be28956066ddfef33813991b77a55005a69dae04bf3b10b"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 2.0.118",
-]
-
 [[package]]
 name = "futures-sink"
 version = "0.3.33"
@@ -400,7 +452,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a77a90a256fce34da66415271e30f94ee91c57b04b8a2c042d9cf3220179deaa"
 dependencies = [
  "futures-core",
- "futures-macro",
  "futures-sink",
  "futures-task",
  "pin-project-lite",
@@ -417,6 +468,19 @@ dependencies = [
  "version_check",
 ]
 
+[[package]]
+name = "getrandom"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ff2abc00be7fca6ebc474524697ae276ad847ad0a6b3faa4bcb027e9a4614ad0"
+dependencies = [
+ "cfg-if",
+ "js-sys",
+ "libc",
+ "wasi",
+ "wasm-bindgen",
+]
+
 [[package]]
 name = "getrandom"
 version = "0.3.4"
@@ -436,8 +500,11 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "300e883d756b2e4ec94e02791f39b04b522276138852cfc41d9fb7e904106099"
 dependencies = [
  "cfg-if",
+ "js-sys",
  "libc",
  "r-efi 6.0.0",
+ "rand_core 0.10.1",
+ "wasm-bindgen",
 ]
 
 [[package]]
@@ -518,6 +585,21 @@ dependencies = [
  "want",
 ]
 
+[[package]]
+name = "hyper-rustls"
+version = "0.27.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "33ca68d021ef39cf6463ab54c1d0f5daf03377b70561305bb89a8f83aab66e0f"
+dependencies = [
+ "http",
+ "hyper",
+ "hyper-util",
+ "rustls",
+ "tokio",
+ "tokio-rustls",
+ "tower-service",
+]
+
 [[package]]
 name = "hyper-util"
 version = "0.1.20"
@@ -717,57 +799,67 @@ version = "3.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8bdc5a74b0feeb5e6a1dc2dd08c34280a61e37668d10a6a3b27ad69d0fb9ce2e"
 dependencies = [
- "aho-corasick",
- "base64",
  "bstr",
  "jaq-core",
- "jiff",
- "libm",
- "log",
- "regex-bites",
- "urlencoding",
 ]
 
 [[package]]
-name = "jiff"
-version = "0.2.31"
+name = "jni"
+version = "0.22.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ccfe6121cbe750cf81efa362d85c0bde7ea298ec43092d3a193baca59cdbd634"
+checksum = "5efd9a482cf3a427f00d6b35f14332adc7902ce91efb778580e180ff90fa3498"
 dependencies = [
- "defmt",
- "jiff-static",
- "jiff-tzdb-platform",
+ "cfg-if",
+ "combine",
+ "jni-macros",
+ "jni-sys",
  "log",
- "portable-atomic",
- "portable-atomic-util",
- "serde_core",
+ "simd_cesu8",
+ "thiserror",
+ "walkdir",
  "windows-link",
 ]
 
 [[package]]
-name = "jiff-static"
-version = "0.2.31"
+name = "jni-macros"
+version = "0.22.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e165e897f662d428f3cd3828a919dbe067c2d42bb1031eede74ef9d27ecdedd2"
+checksum = "a00109accc170f0bdb141fed3e393c565b6f5e072365c3bd58f5b062591560a3"
 dependencies = [
  "proc-macro2",
  "quote",
+ "rustc_version",
+ "simd_cesu8",
  "syn 2.0.118",
 ]
 
 [[package]]
-name = "jiff-tzdb"
-version = "0.1.7"
+name = "jni-sys"
+version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6142247df1a93c2b3587402a19710be3e6e942f1581a1702e76408f2c21d6590"
+checksum = "c6377a88cb3910bee9b0fa88d4f42e1d2da8e79915598f65fb0c7ee14c878af2"
+dependencies = [
+ "jni-sys-macros",
+]
 
 [[package]]
-name = "jiff-tzdb-platform"
-version = "0.1.3"
+name = "jni-sys-macros"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "38c0b942f458fe50cdac086d2f946512305e5631e720728f2a61aabcd47a6264"
+dependencies = [
+ "quote",
+ "syn 2.0.118",
+]
+
+[[package]]
+name = "jobserver"
+version = "0.1.35"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "875a5a69ac2bab1a891711cf5eccbec1ce0341ea805560dcd90b7a2e925132e8"
+checksum = "1c00acbd29eabad4a2392fa0e921c874934dbbf4194312ad20f04a0ed67a3cb3"
 dependencies = [
- "jiff-tzdb",
+ "getrandom 0.4.3",
+ "libc",
 ]
 
 [[package]]
@@ -787,12 +879,6 @@ version = "0.2.186"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "68ab91017fe16c622486840e4c83c9a37afeff978bd239b5293d61ece587de66"
 
-[[package]]
-name = "libm"
-version = "0.2.16"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b6d2cec3eae94f9f509c767b45932f1ada8350c4bdb85af2fcab4a3c14807981"
-
 [[package]]
 name = "linux-raw-sys"
 version = "0.12.1"
@@ -811,6 +897,12 @@ version = "0.4.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0ceec5bc11778974d1bcb055b18002eba7f4b3518b6a0081b3af5f21666da9ad"
 
+[[package]]
+name = "lru-slab"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "112b39cec0b298b6c1999fee3e31427f74f676e4cb9879ed1a121b43661a4154"
+
 [[package]]
 name = "matchit"
 version = "0.8.4"
@@ -847,7 +939,7 @@ checksum = "02bd0af71c67b473010cbbc60715ee815645a4dc942899111f494b4b737d6fda"
 dependencies = [
  "libc",
  "wasi",
- "windows-sys",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]
@@ -894,6 +986,12 @@ version = "1.21.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9f7c3e4beb33f85d45ae3e3a1792185706c8e16d043238c593331cc7cd313b50"
 
+[[package]]
+name = "openssl-probe"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7c87def4c32ab89d880effc9e097653c8da5d6ef28e6b539d313baaacfbafcbe"
+
 [[package]]
 name = "percent-encoding"
 version = "2.3.2"
@@ -906,34 +1004,25 @@ version = "0.2.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a89322df9ebe1c1578d689c92318e070967d1042b512afbe49518723f4e6d5cd"
 
+[[package]]
+name = "pkg-config"
+version = "0.3.33"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "19f132c84eca552bf34cab8ec81f1c1dcc229b811638f9d283dceabe58c5569e"
+
 [[package]]
 name = "png"
 version = "0.18.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "60769b8b31b2a9f263dae2776c37b1b28ae246943cf719eb6946a1db05128a61"
 dependencies = [
- "bitflags 2.13.0",
+ "bitflags",
  "crc32fast",
  "fdeflate",
  "flate2",
  "miniz_oxide",
 ]
 
-[[package]]
-name = "portable-atomic"
-version = "1.13.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c33a9471896f1c69cecef8d20cbe2f7accd12527ce60845ff44c153bb2a21b49"
-
-[[package]]
-name = "portable-atomic-util"
-version = "0.2.7"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c2a106d1259c23fac8e543272398ae0e3c0b8d33c88ed73d0cc71b0f1d902618"
-dependencies = [
- "portable-atomic",
-]
-
 [[package]]
 name = "potential_utf"
 version = "0.1.5"
@@ -952,28 +1041,6 @@ dependencies = [
  "zerocopy",
 ]
 
-[[package]]
-name = "proc-macro-error-attr2"
-version = "2.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "96de42df36bb9bba5542fe9f1a054b8cc87e172759a1868aa05c1f3acc89dfc5"
-dependencies = [
- "proc-macro2",
- "quote",
-]
-
-[[package]]
-name = "proc-macro-error2"
-version = "2.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "11ec05c52be0a07b08061f7dd003e7d7092e0472bc731b4af7bb1ef876109802"
-dependencies = [
- "proc-macro-error-attr2",
- "proc-macro2",
- "quote",
- "syn 2.0.118",
-]
-
 [[package]]
 name = "proc-macro2"
 version = "1.0.106"
@@ -991,9 +1058,9 @@ checksum = "4b45fcc2344c680f5025fe57779faef368840d0bd1f42f216291f0dc4ace4744"
 dependencies = [
  "bit-set",
  "bit-vec",
- "bitflags 2.13.0",
+ "bitflags",
  "num-traits",
- "rand",
+ "rand 0.9.4",
  "rand_chacha",
  "rand_xorshift",
  "regex-syntax",
@@ -1014,6 +1081,63 @@ version = "1.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a1d01941d82fa2ab50be1e79e6714289dd7cde78eba4c074bc5a4374f650dfe0"
 
+[[package]]
+name = "quinn"
+version = "0.11.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0c1a41e437b6bbd489372cd4971de128e85c855f56c57f283d20ff016cf7c0a8"
+dependencies = [
+ "bytes",
+ "cfg_aliases",
+ "pin-project-lite",
+ "quinn-proto",
+ "quinn-udp",
+ "rustc-hash",
+ "rustls",
+ "socket2",
+ "thiserror",
+ "tokio",
+ "tracing",
+ "web-time",
+]
+
+[[package]]
+name = "quinn-proto"
+version = "0.11.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2f4bfc015262b9df63c8845072ce59068853ff5872180c2ce2f13038b970e560"
+dependencies = [
+ "aws-lc-rs",
+ "bytes",
+ "getrandom 0.4.3",
+ "lru-slab",
+ "rand 0.10.2",
+ "rand_pcg",
+ "ring",
+ "rustc-hash",
+ "rustls",
+ "rustls-pki-types",
+ "slab",
+ "thiserror",
+ "tinyvec",
+ "tracing",
+ "web-time",
+]
+
+[[package]]
+name = "quinn-udp"
+version = "0.5.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "35a133f956daabe89a61a685c2649f13d82d5aa4bd5d12d1277e1072a21c0694"
+dependencies = [
+ "cfg_aliases",
+ "libc",
+ "once_cell",
+ "socket2",
+ "tracing",
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "quote"
 version = "1.0.46"
@@ -1042,7 +1166,18 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "44c5af06bb1b7d3216d91932aed5265164bf384dc89cd6ba05cf59a35f5f76ea"
 dependencies = [
  "rand_chacha",
- "rand_core",
+ "rand_core 0.9.5",
+]
+
+[[package]]
+name = "rand"
+version = "0.10.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c7f5fa3a058cd35567ef9bfa5e75732bee0f9e4c55fa90477bef2dfcdbc4be80"
+dependencies = [
+ "chacha20",
+ "getrandom 0.4.3",
+ "rand_core 0.10.1",
 ]
 
 [[package]]
@@ -1052,7 +1187,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d3022b5f1df60f26e1ffddd6c66e8aa15de382ae63b3a0c1bfc0e4d3e3f325cb"
 dependencies = [
  "ppv-lite86",
- "rand_core",
+ "rand_core 0.9.5",
 ]
 
 [[package]]
@@ -1064,13 +1199,28 @@ dependencies = [
  "getrandom 0.3.4",
 ]
 
+[[package]]
+name = "rand_core"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "63b8176103e19a2643978565ca18b50549f6101881c443590420e4dc998a3c69"
+
+[[package]]
+name = "rand_pcg"
+version = "0.10.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "caa0f4137e1c0a72f4c651489402276c8e8e1cf081f3b0ba156d2cbeef09e86a"
+dependencies = [
+ "rand_core 0.10.1",
+]
+
 [[package]]
 name = "rand_xorshift"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "513962919efc330f829edb2535844d1b912b0fbe2ca165d613e4e8788bb05a5a"
 dependencies = [
- "rand_core",
+ "rand_core 0.9.5",
 ]
 
 [[package]]
@@ -1079,12 +1229,6 @@ version = "0.4.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6e1dd4122fc1595e8162618945476892eefca7b88c52820e74af6262213cae8f"
 
-[[package]]
-name = "regex-bites"
-version = "0.1.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b6a15a2fa0bfda9361941c45550896ae87b15cc6c8c939ea350079670332e211"
-
 [[package]]
 name = "regex-syntax"
 version = "0.8.11"
@@ -1104,15 +1248,21 @@ dependencies = [
  "http-body",
  "http-body-util",
  "hyper",
+ "hyper-rustls",
  "hyper-util",
  "js-sys",
  "log",
  "percent-encoding",
  "pin-project-lite",
+ "quinn",
+ "rustls",
+ "rustls-pki-types",
+ "rustls-platform-verifier",
  "serde",
  "serde_json",
  "sync_wrapper",
  "tokio",
+ "tokio-rustls",
  "tower",
  "tower-http",
  "tower-service",
@@ -1122,17 +1272,121 @@ dependencies = [
  "web-sys",
 ]
 
+[[package]]
+name = "ring"
+version = "0.17.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a4689e6c2294d81e88dc6261c768b63bc4fcdb852be6d1352498b114f61383b7"
+dependencies = [
+ "cc",
+ "cfg-if",
+ "getrandom 0.2.17",
+ "libc",
+ "untrusted",
+ "windows-sys 0.52.0",
+]
+
+[[package]]
+name = "rustc-hash"
+version = "2.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6b1e7f9a428571be2dc5bc0505c13fb6bf936822b894ec87abf8a08a4e51742d"
+
+[[package]]
+name = "rustc_version"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cfcb3a22ef46e85b45de6ee7e79d063319ebb6594faafcf1c225ea92ab6e9b92"
+dependencies = [
+ "semver",
+]
+
 [[package]]
 name = "rustix"
 version = "1.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b6fe4565b9518b83ef4f91bb47ce29620ca828bd32cb7e408f0062e9930ba190"
 dependencies = [
- "bitflags 2.13.0",
+ "bitflags",
  "errno",
  "libc",
  "linux-raw-sys",
- "windows-sys",
+ "windows-sys 0.61.2",
+]
+
+[[package]]
+name = "rustls"
+version = "0.23.43"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0283386ce02abc0151e1761d08802dfe86c173b0b494af5cbc086574e453da06"
+dependencies = [
+ "aws-lc-rs",
+ "once_cell",
+ "rustls-pki-types",
+ "rustls-webpki",
+ "subtle",
+ "zeroize",
+]
+
+[[package]]
+name = "rustls-native-certs"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dab5152771c58876a2146916e53e35057e1a4dfa2b9df0f0305b07f611fdea4d"
+dependencies = [
+ "openssl-probe",
+ "rustls-pki-types",
+ "schannel",
+ "security-framework",
+]
+
+[[package]]
+name = "rustls-pki-types"
+version = "1.15.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2f4925028c7eb5d1fcdaf196971378ed9d2c1c4efc7dc5d011256f76c99c0a96"
+dependencies = [
+ "web-time",
+ "zeroize",
+]
+
+[[package]]
+name = "rustls-platform-verifier"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26d1e2536ce4f35f4846aa13bff16bd0ff40157cdb14cc056c7b14ba41233ba0"
+dependencies = [
+ "core-foundation",
+ "core-foundation-sys",
+ "jni",
+ "log",
+ "once_cell",
+ "rustls",
+ "rustls-native-certs",
+ "rustls-platform-verifier-android",
+ "rustls-webpki",
+ "security-framework",
+ "security-framework-sys",
+ "webpki-root-certs",
+ "windows-sys 0.61.2",
+]
+
+[[package]]
+name = "rustls-platform-verifier-android"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f87165f0995f63a9fbeea62b64d10b4d9d8e78ec6d7d51fb2125fda7bb36788f"
+
+[[package]]
+name = "rustls-webpki"
+version = "0.103.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0527518605e68109d875e248ea259b6758801cf165e4b2c2733ae3b51f12535a"
+dependencies = [
+ "aws-lc-rs",
+ "ring",
+ "rustls-pki-types",
+ "untrusted",
 ]
 
 [[package]]
@@ -1159,12 +1413,59 @@ version = "1.0.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9774ba4a74de5f7b1c1451ed6cd5285a32eddb5cccb8cc655a4e50009e06477f"
 
+[[package]]
+name = "same-file"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "93fc1dc3aaa9bfed95e02e6eadabb4baf7e3078b0bd1b4d7b6b0b68378900502"
+dependencies = [
+ "winapi-util",
+]
+
+[[package]]
+name = "schannel"
+version = "0.1.29"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "91c1b7e4904c873ef0710c1f407dde2e6287de2bebc1bbbf7d430bb7cbffd939"
+dependencies = [
+ "windows-sys 0.61.2",
+]
+
+[[package]]
+name = "security-framework"
+version = "3.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b7f4bc775c73d9a02cde8bf7b2ec4c9d12743edf609006c7facc23998404cd1d"
+dependencies = [
+ "bitflags",
+ "core-foundation",
+ "core-foundation-sys",
+ "libc",
+ "security-framework-sys",
+]
+
+[[package]]
+name = "security-framework-sys"
+version = "2.17.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6ce2691df843ecc5d231c0b14ece2acc3efb62c0a398c7e1d875f3983ce020e3"
+dependencies = [
+ "core-foundation-sys",
+ "libc",
+]
+
 [[package]]
 name = "self_cell"
 version = "1.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b12e76d157a900eb52e81bc6e9f3069344290341720e9178cde2407113ac8d89"
 
+[[package]]
+name = "semver"
+version = "1.0.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a7852d02fc848982e0c167ef163aaff9cd91dc640ba85e263cb1ce46fae51cd"
+
 [[package]]
 name = "serde"
 version = "1.0.229"
@@ -1219,18 +1520,6 @@ dependencies = [
  "serde_core",
 ]
 
-[[package]]
-name = "serde_urlencoded"
-version = "0.7.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d3491c14715ca2294c4d6a88f15e84739788c1d030eed8c110436aafdaa2f3fd"
-dependencies = [
- "form_urlencoded",
- "itoa",
- "ryu",
- "serde",
-]
-
 [[package]]
 name = "sha1"
 version = "0.10.7"
@@ -1238,7 +1527,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a978451301f4db1d02937a4ab3ccce137717b81826e79b7d49ffe3244a13c3b8"
 dependencies = [
  "cfg-if",
- "cpufeatures",
+ "cpufeatures 0.2.17",
  "digest",
 ]
 
@@ -1249,10 +1538,16 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a7507d819769d01a365ab707794a4084392c824f54a7a6a7862f8c3d0892b283"
 dependencies = [
  "cfg-if",
- "cpufeatures",
+ "cpufeatures 0.2.17",
  "digest",
 ]
 
+[[package]]
+name = "shlex"
+version = "2.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f8fadd59c855ef2080decdef8ff161eb6661b86933c9d82e5ba29dc602a55aba"
+
 [[package]]
 name = "signal-hook-registry"
 version = "1.4.8"
@@ -1269,6 +1564,22 @@ version = "0.3.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3a219298ac11a56ea9a6d2120044824d6f01aeb034955e7af7bc16858527deea"
 
+[[package]]
+name = "simd_cesu8"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "11031e251abf8611c80f460e19dbdeb54a66db918e49c65a7065b46ac7aec520"
+dependencies = [
+ "rustc_version",
+ "simdutf8",
+]
+
+[[package]]
+name = "simdutf8"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3a9fe34e3e7a50316060351f37187a3f546bce95496156754b601a5fa71b76e"
+
 [[package]]
 name = "slab"
 version = "0.4.12"
@@ -1288,7 +1599,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "52d1cfed4120b4d927bf7c0f86d2087a4a7d6027c906d9f9d525a80573b9be51"
 dependencies = [
  "libc",
- "windows-sys",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]
@@ -1297,6 +1608,12 @@ version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6ce2be8dc25455e1f91df71bfa12ad37d7af1092ae736f3a6cd0e37bc7810596"
 
+[[package]]
+name = "subtle"
+version = "2.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "13c2bddecc57b384dee18652358fb23172facb8a2c51ccc10d74c157bdea3292"
+
 [[package]]
 name = "syn"
 version = "2.0.118"
@@ -1349,7 +1666,7 @@ dependencies = [
  "getrandom 0.4.3",
  "once_cell",
  "rustix",
- "windows-sys",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]
@@ -1374,7 +1691,7 @@ dependencies = [
 
 [[package]]
 name = "tinyflows"
-version = "0.6.1"
+version = "0.7.0"
 dependencies = [
  "async-trait",
  "axum",
@@ -1408,6 +1725,21 @@ dependencies = [
  "zerovec",
 ]
 
+[[package]]
+name = "tinyvec"
+version = "1.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bb4ebadaa0af04fab11ae01eb5f9fdb5f9c5b875506e210e71c07873528baa7f"
+dependencies = [
+ "tinyvec_macros",
+]
+
+[[package]]
+name = "tinyvec_macros"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1f3ccbac311fea05f86f61904b462b55fb3df8837a366dfc601a0161d0532f20"
+
 [[package]]
 name = "tokio"
 version = "1.53.1"
@@ -1421,7 +1753,7 @@ dependencies = [
  "signal-hook-registry",
  "socket2",
  "tokio-macros",
- "windows-sys",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]
@@ -1435,6 +1767,16 @@ dependencies = [
  "syn 2.0.118",
 ]
 
+[[package]]
+name = "tokio-rustls"
+version = "0.26.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1729aa945f29d91ba541258c8df89027d5792d85a8841fb65e8bf0f4ede4ef61"
+dependencies = [
+ "rustls",
+ "tokio",
+]
+
 [[package]]
 name = "tokio-tungstenite"
 version = "0.29.0"
@@ -1460,7 +1802,6 @@ dependencies = [
  "tokio",
  "tower-layer",
  "tower-service",
- "tracing",
 ]
 
 [[package]]
@@ -1469,7 +1810,7 @@ version = "0.6.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4cfcf7e2740e6fc6d4d688b4ef00650406bb94adf4731e43c096c3a19fe40840"
 dependencies = [
- "bitflags 2.13.0",
+ "bitflags",
  "bytes",
  "futures-util",
  "http",
@@ -1499,23 +1840,10 @@ version = "0.1.44"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "63e71662fa4b2a2c3a26f570f037eb95bb1f85397f3cd8076caed2f026a6d100"
 dependencies = [
- "log",
  "pin-project-lite",
- "tracing-attributes",
  "tracing-core",
 ]
 
-[[package]]
-name = "tracing-attributes"
-version = "0.1.31"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7490cfa5ec963746568740651ac6781f701c9c5ea257c58e057f3ba8cf69e8da"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 2.0.118",
-]
-
 [[package]]
 name = "tracing-core"
 version = "0.1.36"
@@ -1542,7 +1870,7 @@ dependencies = [
  "http",
  "httparse",
  "log",
- "rand",
+ "rand 0.9.4",
  "sha1",
  "thiserror",
 ]
@@ -1571,6 +1899,12 @@ version = "1.0.24"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e6e4313cd5fcd3dad5cafa179702e2b244f760991f45397d14d4ebf38247da75"
 
+[[package]]
+name = "untrusted"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8ecb6da28b8a351d773b68d5825ac39017e680750f980f3a1a85cd8dd28a47c1"
+
 [[package]]
 name = "url"
 version = "2.5.8"
@@ -1583,12 +1917,6 @@ dependencies = [
  "serde",
 ]
 
-[[package]]
-name = "urlencoding"
-version = "2.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "daf8dba3b7eb870caf1ddeed7bc9d2a049f3cfdfae7cb521b087cc33ae4c49da"
-
 [[package]]
 name = "utf8_iter"
 version = "1.0.4"
@@ -1610,6 +1938,16 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "walkdir"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "29790946404f91d9c5d06f9874efddea1dc06c5efe94541a7d6863108e3a5e4b"
+dependencies = [
+ "same-file",
+ "winapi-util",
+]
+
 [[package]]
 name = "want"
 version = "0.3.1"
@@ -1699,6 +2037,25 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "web-time"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5a6580f308b1fad9207618087a65c04e7a10bc77e02c8e84e9b00dd4b12fa0bb"
+dependencies = [
+ "js-sys",
+ "wasm-bindgen",
+]
+
+[[package]]
+name = "webpki-root-certs"
+version = "1.0.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b96554aa2acc8ccdb7e1c9a58a7a68dd5d13bccc69cd124cb09406db612a1c9b"
+dependencies = [
+ "rustls-pki-types",
+]
+
 [[package]]
 name = "winapi"
 version = "0.3.9"
@@ -1715,6 +2072,15 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
 
+[[package]]
+name = "winapi-util"
+version = "0.1.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c2a7b1c03c876122aa43f3020e6c3c3ee5c05081c9a00739faf7503aeba10d22"
+dependencies = [
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "winapi-x86_64-pc-windows-gnu"
 version = "0.4.0"
@@ -1727,6 +2093,15 @@ version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f0805222e57f7521d6a62e36fa9163bc891acd422f971defe97d64e70d0a4fe5"
 
+[[package]]
+name = "windows-sys"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "282be5f36a8ce781fad8c8ae18fa3f9beff57ec1b52cb3de0789201425d9a33d"
+dependencies = [
+ "windows-targets",
+]
+
 [[package]]
 name = "windows-sys"
 version = "0.61.2"
@@ -1736,6 +2111,70 @@ dependencies = [
  "windows-link",
 ]
 
+[[package]]
+name = "windows-targets"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9b724f72796e036ab90c1021d4780d4d3d648aca59e491e6b98e725b84e99973"
+dependencies = [
+ "windows_aarch64_gnullvm",
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_gnullvm",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_gnullvm",
+ "windows_x86_64_msvc",
+]
+
+[[package]]
+name = "windows_aarch64_gnullvm"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32a4622180e7a0ec044bb555404c800bc9fd9ec262ec147edd5989ccd0c02cd3"
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09ec2a7bb152e2252b53fa7803150007879548bc709c039df7627cabbd05d469"
+
+[[package]]
+name = "windows_i686_gnu"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e9b5ad5ab802e97eb8e295ac6720e509ee4c243f69d781394014ebfe8bbfa0b"
+
+[[package]]
+name = "windows_i686_gnullvm"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0eee52d38c090b3caa76c563b86c3a4bd71ef1a819287c19d586d7334ae8ed66"
+
+[[package]]
+name = "windows_i686_msvc"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "240948bc05c5e7c6dabba28bf89d89ffce3e303022809e73deaefe4f6ec56c66"
+
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "147a5c80aabfbf0c7d901cb5895d1de30ef2907eb21fbbab29ca94c5b08b1a78"
+
+[[package]]
+name = "windows_x86_64_gnullvm"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "24d5b23dc417412679681396f2b49f3de8c1473deb516bd34410872eff51ed0d"
+
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
+
 [[package]]
 name = "wit-bindgen"
 version = "0.46.0"
@@ -1812,6 +2251,12 @@ dependencies = [
  "synstructure",
 ]
 
+[[package]]
+name = "zeroize"
+version = "1.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e13c156562582aa81c60cb29407084cdb54c4164760106ab78e6c5b0858cf64e"
+
 [[package]]
 name = "zerotrie"
 version = "0.2.4"
diff --git a/Cargo.toml b/Cargo.toml
index 4c8e7a01..80a5344b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "tinyflows"
-version = "0.6.1"
+version = "0.7.0"
 edition = "2024"
 rust-version = "1.85"
 license = "GPL-3.0-or-later"
@@ -22,18 +22,23 @@ include = [
     "/extension/dist/**",
 ]
 
+[[bin]]
+name = "tinyflows"
+path = "src/main.rs"
+required-features = ["chrome-extension"]
+
 [dependencies]
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 async-trait = "0.1"
 thiserror = "2"
 futures-timer = "3"
-futures-util = "0.3"
+futures-util = { version = "0.3", default-features = false, features = ["async-await", "sink", "std"] }
 getrandom = "0.4"
-tracing = "0.1"
-tokio = { version = "1", features = ["macros", "rt-multi-thread", "net", "signal", "sync", "time"] }
-axum = { version = "0.8", features = ["ws"] }
-reqwest = { version = "0.13", default-features = false, features = ["json"] }
+tracing = { version = "0.1", default-features = false, features = ["std"] }
+tokio = { version = "1", features = ["macros", "rt-multi-thread", "sync", "time"] }
+axum = { version = "0.8", default-features = false, features = ["http1", "json", "ws"], optional = true }
+reqwest = { version = "0.13", default-features = false, features = ["json"], optional = true }
 # `caps::host` only: hashing an author-supplied state key (and namespace) into
 # one safe path component, and staging a script in a temporary directory.
 sha2 = { version = "0.10", optional = true }
@@ -47,7 +52,7 @@ fs2 = { version = "0.4", optional = true }
 image = { version = "0.25", default-features = false, features = ["jpeg", "png"], optional = true }
 font8x8 = { version = "0.3", default-features = false, features = ["unicode"], optional = true }
 jaq-core = "3.1.0"
-jaq-std = "3.0.1"
+jaq-std = { version = "3.0.1", default-features = false }
 jaq-json = { version = "2.0.1", features = ["serde"] }
 
 [features]
@@ -55,12 +60,16 @@ jaq-json = { version = "2.0.1", features = ["serde"] }
 # and examples. Mocks are always available inside this crate's own tests.
 default = []
 mock = []
+# Off by default; enables the Chrome browser protocol, native HTTP/WebSocket
+# companion, and the `tinyflows` companion CLI. The core engine has no listener
+# or HTTP client unless a host selects this feature (or `host-caps` below).
+chrome-extension = ["dep:axum", "dep:reqwest", "tokio/net"]
 # Off by default; enables `caps::host` — ready-made capability implementations
 # for a host that runs scripts as child processes of itself and keeps state on
 # its own disk. Off by default because a host with a sandbox wants none of it,
 # and because it is the only thing in the crate that spawns a process or writes
 # a file. Always available inside this crate's own tests.
-host-caps = ["dep:sha2", "dep:tempfile", "tokio/fs", "tokio/process", "tokio/io-util"]
+host-caps = ["dep:reqwest", "dep:sha2", "dep:tempfile", "reqwest/rustls", "tokio/fs", "tokio/process", "tokio/io-util"]
 # Off by default; enables `store` — the durable model around a graph (versioned
 # documents, run records, notes, proposals) and a JSON file-backed store for it.
 # A host with its own catalog or database wants none of it, so it is not part of
@@ -71,7 +80,6 @@ graph-debug = ["dep:image", "dep:font8x8"]
 
 [dev-dependencies]
 proptest = "1"
-async-trait = "0.1"
 # `caps::host` compiles inside this crate's own tests whether or not the
 # `host-caps` feature is on (the same rule `caps::mock` follows), so what that
 # feature would switch on has to be present for a test build too. An optional
@@ -79,4 +87,5 @@ async-trait = "0.1"
 sha2 = "0.10"
 tempfile = "3"
 fs2 = "0.4"
+reqwest = { version = "0.13", default-features = false, features = ["json", "rustls"] }
 tokio = { version = "1", features = ["fs", "process", "io-util"] }
diff --git a/README.md b/README.md
index e05de14d..0f24437b 100644
--- a/README.md
+++ b/README.md
@@ -85,7 +85,8 @@ Rust 2024 · MSRV 1.85 · `#![forbid(unsafe_code)]` · GPL-3.0-or-later.
   secrets; the crate never sees them.
 - Versioned wire format: graph `schema_version` and per-node `type_version`, with
   a `migrate` framework for load-time upgrades.
-- Optional Chrome workflow companion: a native loopback relay and MV3 extension
+- Optional Chrome workflow companion (behind the `chrome-extension` Cargo
+  feature): a native loopback relay and MV3 extension
   execute explicit `tool_call` nodes with `slug: "browser"` in user-shared tabs,
   while every other tool remains with the embedding host's invoker.
 
@@ -293,7 +294,7 @@ Install Rust 1.85 or newer with [rustup](https://rustup.rs/), then:
 ```sh
 cargo build
 cargo test                 # unit + compiler + engine tests (mocks auto-available)
-cargo test --all-features  # also exercises the `mock` capability impls explicitly
+cargo test --all-features  # also exercises optional host and Chrome support
 ```
 
 The Chrome extension is a separate local package:
diff --git a/docs/chrome-extension.md b/docs/chrome-extension.md
index 0dae66fe..6038d6c9 100644
--- a/docs/chrome-extension.md
+++ b/docs/chrome-extension.md
@@ -2,26 +2,46 @@
 
 TinyFlows can drive ordinary signed-in Chrome tabs through an unpacked Manifest V3 extension. The native companion remains the workflow runtime: it validates and executes `WorkflowGraph`s, owns retries and credentials, and dispatches non-browser integrations. The extension receives only a correlated browser action and the tab already bound to that run.
 
-## Build, install, and pair
+The Rust protocol, relay, and companion CLI are behind the `chrome-extension`
+Cargo feature. They are absent from the default engine-only build.
+
+Install the companion CLI from crates.io with:
 
 ```bash
-cd extension
-npm ci
-npm run verify
-npm run build
-cd ..
-cargo run -- extension path
+cargo install tinyflows --features chrome-extension
+```
+
+## Install, build, and pair
+
+After `cargo install`, the `tinyflows` binary is on your `PATH`. It materializes
+its embedded, versioned extension into a local directory and drives the
+companion, so nothing below needs a source checkout:
+
+```bash
+tinyflows extension path
 ```
 
 Open `chrome://extensions`, enable Developer mode, choose **Load unpacked**, and select the printed directory. The CLI materializes its embedded, versioned extension there, so the path remains valid after `cargo install` removes its build sources. Copy the extension id shown by Chrome, then start the companion:
 
 ```bash
-cargo run -- pair
-cargo run -- companion start \
+tinyflows pair
+tinyflows companion start \
   --extension-id <32-character-extension-id> \
   --workflows-dir "$PWD/workflows"
 ```
 
+To rebuild and test the extension from a source checkout instead, build the
+package first and then compile the companion from that checkout so the fresh
+`extension/dist` output is embedded:
+
+```bash
+cd extension
+npm ci
+npm run verify
+cd ..
+cargo run --features chrome-extension -- extension path
+```
+
 `pair` prints a loopback relay URL and a pairing token. Paste both into the toolbar popup. The token is stored in `~/.tinyflows/credentials/chrome-extension-relay.secret` with mode `0600` on Unix. It is carried in `Sec-WebSocket-Protocol`, never in the URL. Rotate it with `tinyflows pair --rotate`, restart the companion, and pair the extension again.
 
 Click **Share with TinyFlows** on an ordinary HTTP(S) tab. Chrome places it in the clearly named **TinyFlows shared tabs** group and shows its debugger banner. Moving the tab out of that group, closing it, or detaching the debugger revokes access immediately. The side panel starts a workflow in its own shared tab; the CLI always requires an explicit tab:
diff --git a/extension/package-lock.json b/extension/package-lock.json
index bf6287a0..9dc8cd4b 100644
--- a/extension/package-lock.json
+++ b/extension/package-lock.json
@@ -1518,16 +1518,16 @@
       }
     },
     "node_modules/@typescript-eslint/typescript-estree/node_modules/brace-expansion": {
-      "version": "5.0.7",
-      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-5.0.7.tgz",
-      "integrity": "sha512-7oFy703dxfY3/NLxC1fh2SUCQ0H9rmAY+5EpDVfXjUTTs+HEwR2nYaqLv+GWcTsumwxPfiz6CzCNkwXwBUwqCA==",
+      "version": "5.0.9",
+      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-5.0.9.tgz",
+      "integrity": "sha512-ScQ4IuvIEF1TMlP7Zt+vjJ//9zlPb2SDcxWxM3bk8s6t6GGdJ7KO1dCcTidOPJKePW30LE/2cT7wCyPho9/Wxg==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
         "balanced-match": "^4.0.2"
       },
       "engines": {
-        "node": "18 || 20 || >=22"
+        "node": "20 || >=22"
       }
     },
     "node_modules/@typescript-eslint/typescript-estree/node_modules/minimatch": {
@@ -1856,9 +1856,9 @@
       "license": "MIT"
     },
     "node_modules/brace-expansion": {
-      "version": "1.1.16",
-      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.16.tgz",
-      "integrity": "sha512-IDw48K2/2kRkg9LdJxurvq3lV3aBgq0REY89duEqFRthjlPdXHKMj7EnQOXVckxzgisinf3nHfrcE2FufFLXMw==",
+      "version": "1.1.18",
+      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.18.tgz",
+      "integrity": "sha512-Edep/X9fGqVNmzKBVsDYIOtD+z1tuezV70LBjdCst9Tqu76lsnvRiZ6oTic1n+/BIwX6QDGAO94PN4N2SADvtw==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -2425,9 +2425,9 @@
       }
     },
     "node_modules/glob/node_modules/brace-expansion": {
-      "version": "2.1.2",
-      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-2.1.2.tgz",
-      "integrity": "sha512-w5JZcKgdhDOgOwm8H+KgbosopHMuGcl6qbulwjtz3SM7I7P3yW1eAjzMPLrIE+NQ9vjgANKHWeMHnrT0OXW1oA==",
+      "version": "2.1.4",
+      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-2.1.4.tgz",
+      "integrity": "sha512-hGfVzPxthbf3+2yjg/RBs60cB0FhqBS/zvdV/4wn4/BmN0bNMMHPc4V/BbFieqf1TKAGGAHnY4eSjajCl0f2Xg==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
@@ -2635,9 +2635,9 @@
       "license": "MIT"
     },
     "node_modules/js-yaml": {
-      "version": "4.3.0",
-      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-4.3.0.tgz",
-      "integrity": "sha512-1td788aAnnZ5qs7V2QIRl1owjtYpbKt749Y3xauqQgwIIGF/xXWz1wMTEBx5O3LK3lXLVuqXPdPxj2BoFHaW9Q==",
+      "version": "4.3.1",
+      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-4.3.1.tgz",
+      "integrity": "sha512-CY6crGq313MX8GkwvB7tzgp99vjQxY1++5y10/BKN/GUfHqWaOGQMNZkBvqSzsZKWk/ijwHlWzzkLulsGHhjWQ==",
       "dev": true,
       "funding": [
         {
@@ -2808,9 +2808,9 @@
       "license": "MIT"
     },
     "node_modules/nanoid": {
-      "version": "3.3.16",
-      "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-3.3.16.tgz",
-      "integrity": "sha512-bzlKTyNJ7+LdGIIwy8ijFpIqEQIvafahV7eYykJ8Cvh42EdJeODoJ6gUJXpQJvej1BddH8OqTXZNE/KfbWAu8Q==",
+      "version": "3.3.18",
+      "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-3.3.18.tgz",
+      "integrity": "sha512-DTg4MJbGMWkfi6VZFdNt2/caMbQy4Ou+Op/hJQvGEWcnVfoA1QA+xzRKAzw9jD6+GVOOeYr/mIcuDSdug6F6+w==",
       "dev": true,
       "funding": [
         {
@@ -3025,9 +3025,9 @@
       }
     },
     "node_modules/postcss": {
-      "version": "8.5.22",
-      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.5.22.tgz",
-      "integrity": "sha512-KBDEIpLrvpv16pp3K0Fw+UCoZfopFjjgeB+0tA/aaThfEE74kKDLrgg603YvOWJyg3+WYtyq3xYsQWsIyZlPqQ==",
+      "version": "8.5.26",
+      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.5.26.tgz",
+      "integrity": "sha512-u82N74LFzG8ca+dD8puPnplTXoGH4fTPpVGuIbt36G3qvNlkvfD0lEAZSxaly3KX8TS/L1A1gsCEmvKmBcVbkQ==",
       "dev": true,
       "funding": [
         {
@@ -3045,7 +3045,7 @@
       ],
       "license": "MIT",
       "dependencies": {
-        "nanoid": "^3.3.16",
+        "nanoid": "^3.3.17",
         "picocolors": "^1.1.1",
         "source-map-js": "^1.2.1"
       },
@@ -3384,16 +3384,16 @@
       }
     },
     "node_modules/test-exclude/node_modules/brace-expansion": {
-      "version": "5.0.7",
-      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-5.0.7.tgz",
-      "integrity": "sha512-7oFy703dxfY3/NLxC1fh2SUCQ0H9rmAY+5EpDVfXjUTTs+HEwR2nYaqLv+GWcTsumwxPfiz6CzCNkwXwBUwqCA==",
+      "version": "5.0.9",
+      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-5.0.9.tgz",
+      "integrity": "sha512-ScQ4IuvIEF1TMlP7Zt+vjJ//9zlPb2SDcxWxM3bk8s6t6GGdJ7KO1dCcTidOPJKePW30LE/2cT7wCyPho9/Wxg==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
         "balanced-match": "^4.0.2"
       },
       "engines": {
-        "node": "18 || 20 || >=22"
+        "node": "20 || >=22"
       }
     },
     "node_modules/test-exclude/node_modules/minimatch": {
diff --git a/src/expr.rs b/src/expr.rs
index 2c9978cc..1abe1742 100644
--- a/src/expr.rs
+++ b/src/expr.rs
@@ -295,11 +295,6 @@ fn is_ident(seg: &str) -> bool {
     chars.all(|c| c == '_' || c == '-' || c.is_ascii_alphanumeric())
 }
 
-/// jaq standard-library builtins that must not be exposed to workflow
-/// expressions. `env` (aka `$ENV`) reads the embedding process's environment
-/// and would leak host secrets into node output; it is stripped before compile.
-const EXPR_DENIED_BUILTINS: &[&str] = &["env"];
-
 /// Repairs a hybrid expression that mixes the simple-path shorthand's bare
 /// scope key (e.g. `item`, with no leading dot) with a real jq pipe, such as
 /// `"item.labels | any(.name == \"in progress\") | not"`. That whole string
@@ -375,17 +370,48 @@ fn run_jq(program: &str, scope: &Value) -> Value {
         return Value::Null;
     };
 
+    // `jaq-std` keeps its jq-authored definitions in one file, including
+    // wrappers around optional native functions. Keep the definitions that
+    // compile against `base_funs`; omit wrappers for the disabled bundles.
     let defs = jaq_core::defs()
-        .chain(jaq_std::defs())
+        .chain(jaq_std::defs().filter(|def| {
+            !(matches!(
+                def.name,
+                "stderr"
+                    | "debug"
+                    | "halt_error"
+                    | "logb"
+                    | "significand"
+                    | "pow10"
+                    | "drem"
+                    | "nexttoward"
+                    | "scalb"
+                    | "gamma"
+                    | "capture_of_match"
+                    | "test"
+                    | "scan"
+                    | "match"
+                    | "capture"
+                    | "splits"
+                    | "sub"
+                    | "gsub"
+                    | "todate"
+                    | "fromdate"
+                    | "@html"
+                    | "@htmld"
+                    | "@uri"
+                    | "@urid"
+                    | "@base64"
+                    | "@base64d"
+            ) || (def.name == "split" && def.args.len() == 2))
+        }))
         .chain(jaq_json::defs());
-    // Security: workflow expressions are host/agent-authored data, so the jq
-    // standard library's process-facing builtins must not be reachable. In
-    // particular jaq-std's `env`/`$ENV` dumps the embedding process's entire
-    // environment (API keys, tokens) into node output — a secret-exfiltration
-    // vector. A `Fun` is a `(name, …, …)` tuple, so we filter jaq-std's set by
-    // name before compiling. jaq-core/jaq-json builtins are pure and kept whole.
+    // Keep the minimal, value-generic standard library. Supplementary native
+    // builtins are deliberately not compiled: besides pulling in time, regex,
+    // formatting, and specialist-math stacks, that set includes process-facing
+    // `env`/`$ENV`, which could leak host secrets into workflow output.
     let funs = jaq_core::funs()
-        .chain(jaq_std::funs().filter(|fun| !EXPR_DENIED_BUILTINS.contains(&fun.0)))
+        .chain(jaq_std::base_funs())
         .chain(jaq_json::funs());
 
     let loader = Loader::new(defs);
@@ -444,11 +470,33 @@ mod tests {
         assert_eq!(evaluate(&json!("=env"), &scope), Value::Null);
         assert_eq!(evaluate(&json!("=env.PATH"), &scope), Value::Null);
         assert_eq!(evaluate(&json!("=$ENV.PATH"), &scope), Value::Null);
-        // A pure jq builtin (from jaq-core/jaq-json) still works — we only
-        // stripped the process-facing one.
+        // A pure jq builtin still works; only supplementary native builtins
+        // are omitted.
         assert_eq!(evaluate(&json!("=[1,2,3]|length"), &scope), json!(3));
     }
 
+    #[test]
+    fn optional_native_builtins_are_not_reachable() {
+        let scope = json!({});
+        assert_eq!(evaluate(&json!("=now | ."), &scope), Value::Null);
+        assert_eq!(
+            evaluate(&json!("=\"<b>\" | escape_html"), &scope),
+            Value::Null
+        );
+        assert_eq!(
+            evaluate(&json!("=\"abc\" | matches(\"a\"; \"\")"), &scope),
+            Value::Null
+        );
+        assert_eq!(
+            evaluate(
+                &json!("=\"2024-01-01T00:00:00Z\" | fromdateiso8601"),
+                &scope
+            ),
+            Value::Null
+        );
+        assert_eq!(evaluate(&json!("=9 | sqrt"), &scope), Value::Null);
+    }
+
     #[test]
     fn missing_path_is_null() {
         let scope = json!({ "user": { "email": "a@b.com" } });
diff --git a/src/lib.rs b/src/lib.rs
index d689dc50..31e2cafd 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -23,10 +23,12 @@
 /// expression reads from, and whether it reads as prose.
 pub mod bindings;
 /// Browser automation protocol, action validation, and tool routing.
+#[cfg(feature = "chrome-extension")]
 pub mod browser;
 pub mod caps;
 pub mod catalog;
 /// Native companion pairing, tab authorization, relay, and control lifecycle.
+#[cfg(feature = "chrome-extension")]
 pub mod companion;
 pub mod compiler;
 pub mod data;
diff --git a/tests/browser_routing_e2e.rs b/tests/browser_routing_e2e.rs
index 107238d1..a4ef886a 100644
--- a/tests/browser_routing_e2e.rs
+++ b/tests/browser_routing_e2e.rs
@@ -1,6 +1,6 @@
 //! Mixed browser and integration routing through ordinary `tool_call` nodes.
 
-#![cfg(feature = "mock")]
+#![cfg(all(feature = "mock", feature = "chrome-extension"))]
 
 use std::sync::{Arc, Mutex};
 
diff --git a/tests/cli_e2e.rs b/tests/cli_e2e.rs
index 6bc0eead..aec25002 100644
--- a/tests/cli_e2e.rs
+++ b/tests/cli_e2e.rs
@@ -1,5 +1,7 @@
 //! CLI smoke tests for the tinyflows binary.
 
+#![cfg(feature = "chrome-extension")]
+
 use std::path::PathBuf;
 use std::process::Command;
 use std::time::{SystemTime, UNIX_EPOCH};