Skill files (.claude/skills/, .cursor/rules/*.mdc,
AGENTS.md, .windsurfrules) are becoming a core part of
AI-assisted development workflows. The problem: they
scatter across projects, diverge silently, and every new
repo means rebuilding behavioral config from scratch. Each
tool uses a different format and location. Skilldeck keeps one local library and deploys to any tool in the correct format automatically. Ten built-in target profiles cover Claude Code, Cursor, Copilot, Windsurf, Codex, and more. Drift detection shows when a deployed skill has fallen out of sync with the library version. Bidirectional sync lets you pull improvements back from a project into the library. The interesting part technically: the entire app was built by Claude Code using a harness engineering methodology — a ground truth JSON file, Playwright E2E verification tests, a regression gate based on a surfaces map, and a feature intake protocol. 31 features across multiple autonomous sessions with no manual application code. I wrote two articles about the harness approach if that side is interesting. No cloud, no backend, local filesystem only. Windows/macOS/Linux. Open source. github.com/ali-erfan-dev/skilldeck |