Sigil

Sigil is a Scheme dialect that compiles to standalone binaries for desktop and web, targeting users who want R7RS Small compatibility without runtime dependencies. The current master branch tracks version 0.22.11, which fixes memory-safety issues and introduces opt-in native dependencies, while the project has recently shifted its license to BSD-3-Clause. The codebase is heavily shell-based (68.5%) with JavaScript and Python components, and it integrates tightly with Emacs for a REPL-driven workflow. A notable recent optimization reduced native-codegen web build sizes by roughly 70%, and the toolchain now pins Guix for reproducible releases.

The project’s most significant disclosure is its "AI Disclaimer," which admits the codebase was developed almost entirely using Claude Code (Opus 4.5). This stands in direct contrast to the platform it resides on, as Codeberg recently updated its Terms of Use to restrict LLM-generated content and ban cryptocurrency projects. While Sigil offers standard features like pattern matching, delimited continuations, and channel-based concurrency, the heavy reliance on a specific AI model for its development makes it a prime candidate for the very policy changes currently being enforced on its host.