Go Shell

A minimal, extensible shell implemented in Go, designed for learning, experimentation, and as a foundation for custom scripting environments.

Tech Stack

• Language: Go (>=1.18)
• Standard Library: os/exec, bufio, fmt, strings, etc.
• No external dependencies

Features

• REPL loop with customizable prompt
• Built-in commands: cd, pwd, echo, history, help, exit, export, source, read
• Command history with configurable size
• Environment variable management (export)
• Source external script files (source)
• Executes external system commands (e.g., ls, cat)
• Easily extensible with new built-in commands

Getting Started

Build & Run

git clone <repo-url>
cd go-shell
go run cmd/main.go

Example Usage

> pwd
/home/user/go-shell
> echo Hello World
Hello World
> export FOO=bar
> source script.sh
> history
pwd
echo Hello World
export FOO=bar
source script.sh
history
> exit

Project Structure

cmd/main.go         # Entry point
internal/shell.go   # Shell logic, REPL, built-ins
internal/models.go  # Command struct and parsing
internal/           # Other internal logic

Adding a Built-in Command

1. Implement a function with signature: func(*Shell, []string) error
2. Add it to the Builtins map in DefaultBuiltins()

Testing

Run all tests:

go test ./...