AI platform agnosticism¶

Apothem is designed around a single principle: your governance configuration should outlast any single AI platform. The shared apothem profile (the source tree under src/apothem/, plus the root CLAUDE.md and settings*.json) encodes your rules, mandates, hooks, and plans in platform-neutral form; per-harness adapters under src/apothem/harnesses/<harness>/ translate it into the format each of the eleven supported platforms requires (Claude Code, Cursor, Gemini CLI, GitHub Copilot, Codex, Windsurf, OpenCode, Antigravity, Open-Claw, Hermes, Qwen Code).

The problem¶

Every AI coding harness has its own config format:

Claude Code: CLAUDE.md + settings.json
Cursor: .cursor/rules/*.mdc
GitHub Copilot: .github/copilot-instructions.md
Windsurf: .windsurfrules
Codex: AGENTS.md

Without apothem, you maintain N separate config files that drift apart over time.

The apothem solution¶

One shared apothem profile (the source tree)
    CLAUDE.md
    src/apothem/rules/
         |
         v
    Adapter layer (HarnessAdapter protocol — src/apothem/harnesses/<harness>/)
         |
         +---> Claude Code adapter   -> ~/.claude/
         +---> Cursor adapter        -> .cursor/rules/*.mdc
         +---> Copilot adapter       -> .github/copilot-instructions.md
         +---> Windsurf adapter      -> .windsurfrules
         +---> ...

You edit the shared profile once, then run apothem update --harness <name> for each installed harness to propagate the change. apothem harnesses list prints the installed set.

Why poly + loom¶

The name encodes the design: poly (many AI platforms) woven through a loom (the governance framework: rules, mandates, hooks, and plans crossing like warp and weft). The governance layer is the loom; the harnesses are the threads it weaves.

Portability guarantees¶

Rules marked portability: universal are guaranteed translatable to every supported harness. Rules marked portability: project-specific may require per-harness override documentation in the rule body.