or ) or a deterministic stacked pipeline that executes multiple engines in order.

. Engines expose a shared contract:

: stable engine id such as or
• : dashboard-readable name
• : whether the engine can execute a compression mode
• : transforms text/messages and returns stats

registers the built-in engines before compression runs. This lets preview, runtime compression, stacked mode, tests, and future engines use the same execution path.

• , , and modes

.

fewer output tokens, average output savings in benchmarks with a range, and a input-compression tool. OmniRoute uses the Caveman input-side number when documenting stacked prompt/context savings; Caveman output mode remains a separate response-behavior feature.

, , , Vitest/Jest/Pytest, Cargo/Go tests, TypeScript/Vite/Webpack builds, ESLint, npm audit/installs, Docker logs, shell /, stack traces, and generic logs
• and global filters in

.

.

savings for command-output compression. Its README example shows a 30-minute Claude Code session going from tokens to , or saved.

rtk -> caveman

in compression settings or through compression combos.

combined = 1 - (1 - RTK savings) * (1 - Caveman input savings)
average  = 1 - (1 - 0.80) * (1 - 0.46) = 89.2%
range    = 1 - (1 - 0.60..0.90) * (1 - 0.46) = 78.4-94.6%

: stores mode, pipeline, RTK config, language config, and default marker
• : maps a compression combo to a routing combo
• and

.

node --import tsx/esm --test tests/unit/compression/rtk-*.test.ts tests/unit/compression/pipeline-integration.test.ts tests/unit/compression/context-compression-api.test.ts
node --import tsx/esm --test tests/unit/compression/*.test.ts tests/golden-set/*.test.ts tests/integration/compression-pipeline.test.ts tests/unit/api/compression/compression-api.test.ts
npm run typecheck:core