CometixCode

What does CometixCode do?

CometixCode describes itself as "a terminal-based AI coding assistant, written in Rust as a 1:1 reimplementation of Anthropic's Claude Code." The README says it is an unofficial project, not affiliated with Anthropic: "Claude" and "Claude Code" are trademarks of Anthropic. The port follows Claude Code file by file rather than reinventing the architecture; a TypeScript component maps to a Rust component, a hook to a hook, and deliberate deviations are recorded in the source where they happen.

Claude Code's terminal UI is TypeScript on React plus Ink. CometixCode reproduces it in Rust on CometixTUI, a fork of iocraft with the primitives this port needs (row-level diffing, event propagation, SIGCONT self-healing, IME cursor, bracketed paste, grid layout). The README states that large parts of the interactive loop, tool execution, permissions, MCP and slash commands are implemented; other areas are partial.

Key facts

• Licence: AGPL-3.0-only.
• Language: Rust (edition 2024), Rust 1.88 or newer.
• No system libraries, no pkg-config required to build.
• Build: cargo build --release, cargo run --release; the binary is cometix.
• Cross-compiling for Windows: rustup target add x86_64-pc-windows-gnu, cargo build --release --target x86_64-pc-windows-gnu. A mingw-w64 toolchain has to be on PATH; dependencies link statically so the .exe needs no DLLs alongside it.
• File search shells out to rg (ripgrep), matching Claude Code's shape; /doctor reports which binary is in use. USE_BUILTIN_RIPGREP=0 forces the host binary.
• Testing is gated on just test, which runs cargo-nextest with one process per test, because the codebase has process-wide state (environment variables, OnceLock caches) that leaks between threads in cargo test.
• Dependencies built by the same maintainer or project: CometixTUI (TUI framework fork of iocraft), marked-rs (Markdown parser port), anthropic-sdk-rs (API client port).
• Nucleo by the Helix editor project is the fuzzy matcher behind file, command and agent completion.

What does it replace, and where does it fall short?

CometixCode replaces Claude Code for a developer who wants a Rust terminal binary with the same shape, under AGPL-3.0. It appears on the open-source alternatives to Claude Code page.

Where it falls short: the README says CometixCode is a work in progress; large parts of the interactive loop, tool execution, permissions, MCP and slash commands are implemented, but other areas are partial. Anthropic's hosted Claude Code is the official product and has features that may not be in this port. The AGPL-3.0 licence has a stronger copyleft than Claude Code's own licence, which may matter in some deployments. There is no stated performance benchmark against Claude Code.

How does CometixCode run?

Build and run from source with Cargo: cargo build --release, then cargo run --release. The binary is cometix. For Windows cross-compiling: rustup target add x86_64-pc-windows-gnu, then cargo build --release --target x86_64-pc-windows-gnu, with a mingw-w64 toolchain on PATH.

File search uses rg (ripgrep). Resolution order: vendor/ripgrep/<arch>-<os>/rg next to the executable, then the same path in the source tree, then the host's rg on PATH. Drop a pinned ripgrep under vendor/ripgrep/, or just have rg installed. /doctor reports which one is in use.

Who is CometixCode for?

A developer who wants Claude Code's terminal shape as a Rust binary, under AGPL-3.0, and is comfortable with a work-in-progress port. For a VS Code fork laid out like Cursor, see OpenCursor. For a VS Code fork around the Agent Client Protocol, see Volt. For a fuller alternatives list including Codex, OpenCode and Goose, see the open-source alternatives to Claude Code page. For the official product, Claude Code is the paid tool.

What limits does the README state?

• "This is an independent reimplementation built by reading the published Claude Code CLI." Unofficial, not affiliated with Anthropic.
• "It is a work in progress. Large parts of the interactive loop, tool execution, permissions, MCP and slash commands are implemented; other areas are partial."
• "cargo test is not a valid gate for this crate. It runs the whole suite as threads in one process, and this codebase has process-wide state (env vars, OnceLock caches) that leaks between tests as a result."
• Builds and runs; the README does not state model costs, performance benchmarks or feature parity figures against Claude Code.

Questions people ask

Is CometixCode open source?

Yes. The LICENSE file at the repository root is AGPL-3.0-only, an OSI-approved licence. The README says CometixCode is an unofficial project, not affiliated with Anthropic: "Claude" and "Claude Code" are trademarks of Anthropic. The port is derived from the ClaudeCodeRev analysis of Claude Code's published CLI.

Can I use CometixCode commercially?

AGPL-3.0 allows commercial use, modification and distribution, but adds a network-use clause: if you modify CometixCode and let others use it over a network, you must offer them the source. For an internal install that is a terminal CLI, that is usually not a problem. Read the LICENSE file for the exact terms.

What does it need to build?

Rust 1.88 or newer (edition 2024). The README says: nothing else, no system libraries, no pkg-config. For Windows cross-compilation, a mingw-w64 toolchain on PATH. Four dependencies compile C or assembly (onig_sys, ring, tree-sitter, tree-sitter-bash), and they link statically so the resulting .exe needs no DLLs alongside it.

How does CometixCode compare with Claude Code?

Claude Code is Anthropic's official TypeScript product. CometixCode is a Rust reimplementation that follows Claude Code file by file, built on CometixTUI (an iocraft fork) and anthropic-sdk-rs. The README says CometixCode is a work in progress with partial coverage of some areas. The open-source alternatives to Claude Code page compares it with Codex, Goose, OpenCode and others.

What is CometixTUI?

CometixTUI is a fork of iocraft, a Rust framework that lets you build terminal user interfaces with a React-style retained-mode API (components, hooks, declarative elements). The README says the fork carries primitives this port needs (row-level diffing, event propagation, SIGCONT self-healing, IME cursor, bracketed paste, grid layout). It is maintained alongside CometixCode by the same project.

Sources

• CometixCode README and LICENSE: github.com/Haleclipse/CometixCode, read 2026-11-02.