ln-831-oss-replacer（ln 831 oss 替代品）

Paths: File paths (shared/, references/, ../ln-*) are relative to skills repo root. If not found at CWD, locate this SKILL.md directory and go up one level for repo root. If shared/ is missing, fetch files via WebFetch from https://raw.githubusercontent.com/levnikolaevich/claude-code-skills/master/skills/{path}.

ln-831-oss-replacer

Type: L3 Worker Category: 8XX Optimization

Executes OSS replacement plans from ln-645-open-source-replacer. For each custom module with a viable OSS alternative: install package, rewrite imports, run verification, then keep or discard atomically.

Overview

Workflow

Phases: Pre-flight -> Load Plan -> Prioritize -> Replace Loop -> Report

Phase 0: Pre-flight Checks

MANDATORY READ: Load shared/references/ci_tool_detection.md for test detection. MANDATORY READ: Load shared/references/mcp_tool_preferences.md and shared/references/mcp_integration_patterns.md

Use hex-line first for local code edits and reads when available, and use hex-graph first when cross-file reference checks materially improve replacement safety. If MCP is unavailable, unsupported, or not indexed, continue with built-in Read/Grep/Glob/Bash and state the fallback in the summary.

Runtime Coordination

Managed runs receive deterministic runId and exact summaryArtifactPath from ln-830. Standalone runs remain supported; if runtime arguments are omitted, generate a standalone run-scoped artifact before returning.

Phase 1: Load Migration Plan

From audit report, extract:

If no audit report exists, analyze the target module and search Context7 or Ref for viable OSS alternatives.

MANDATORY READ: Load shared/references/research_tool_fallback.md

Phase 2: Prioritize Replacements

Phase 3: Replace Loop (Keep/Discard)

Per-module cycle:

FOR each replacement candidate:
  1. INSTALL: add the OSS package
  2. REWRITE: update imports and call sites using api_mapping
  3. VERIFY: run tests
     IF tests fail -> DISCARD and revert all changes for this candidate
  4. KEEP: only after verification passes
  5. DELETE: remove old custom module after keep
  6. LOG: record result for the final report

Stop conditions:

Atomic revert on discard:

Safety rules:

Phase 4: Report Results

Configuration

Options:
  audit_report: "docs/project/codebase_audit.md"
  target_module: ""
  min_confidence: "MEDIUM"
  run_tests: true
  require_test_coverage: true
  delete_old_module: true

Error Handling

References

• ../ln-645-open-source-replacer/SKILL.md
• shared/references/ci_tool_detection.md
• shared/references/research_tool_fallback.md

Runtime Summary Artifact

MANDATORY READ: Load shared/references/coordinator_summary_contract.md

Emit a modernization-worker summary envelope.

Managed mode:

• ln-830 passes deterministic runId and exact summaryArtifactPath
• write the summary to the provided summaryArtifactPath

Standalone mode:

• omit runId and summaryArtifactPath
• write .hex-skills/runtime-artifacts/runs/{run_id}/modernization-worker/ln-831--{identifier}.json

Monitor (2.1.98+): For install + test verification loops expected >30s, use Monitor. Fallback: Bash(run_in_background=true).

Definition of Done

• Migration plan loaded or target module analyzed
• Candidates prioritized by confidence and code-reduction value
• Each replacement executed atomically with keep/discard verification
• Discarded replacements fully reverted
• Kept replacements remove old custom code only after verification passes
• Report captures applied, discarded, skipped replacements, and LOC removed
• modernization-worker summary artifact written to the managed or standalone path

Version: 1.0.0 Last Updated: 2026-03-08