Adds permafrost to DevOps & Performance as an external-link entry (same pattern as AgentLint / maestro-orchestrate).
What it is: a Claude Code plugin + zero-dependency passthrough proxy that freezes the prompt prefix (deterministic tool sort, env-block freezing, nonce stabilization, canonical serialization) so DeepSeek's automatic context cache keeps hitting when you run Claude Code against api.deepseek.com/anthropic. Ships /permafrost:status|doctor|benchmark|wrap commands, a SessionStart hook, and a savings statusline; installable via /plugin marketplace add jianzhichun/permafrost.
Checklist: real use case (DeepSeek users' cache hit rate); no duplicate in the list; standard plugin structure (.claude-plugin/plugin.json, commands/, hooks/), validated with claude plugin validate --strict; tested — unit + smoke suites in CI, plus live e2e against real Claude Code and the real DeepSeek API (66% hit / 64% cost cut, reproducible with e2e/run_claude_code.sh). MIT, fully local, no telemetry.