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ln-830-code-modernization-coordinator

Type: L2 Domain Coordinator Category: 8XX Optimization

Coordinates code modernization by delegating to L3 workers: ln-831 (OSS replacer) and ln-832 (bundle optimizer). Executes migration plans from 6XX audit findings.

Overview

Aspect	Details
Input	Audit report (ln-645 migration plan) OR target module
Output	Modernized codebase with verification proof
Workers	ln-831 (OSS replacer), ln-832 (bundle optimizer)

Workflow

Phases: Pre-flight → Analyze Input → Delegate → Collect → Verify → Report

Phase 0: Pre-flight Checks

Check	Required	Action if Missing
Audit report OR target module	Yes	Block modernization
Git clean state	Yes	Block (need clean baseline for revert)
Test infrastructure	Yes	Block (workers need tests for keep/discard)

MANDATORY READ: Load shared/references/ci_tool_detection.md for test/build detection.

Phase 1: Analyze Input

Worker Selection

Condition	ln-831	ln-832
ln-645 findings present (OSS candidates)	Yes	No
JS/TS project with package.json	No	Yes
Both conditions	Yes	Yes
Target module specified	Yes	No

Stack Detection

Indicator	Stack	ln-832 Eligible
package.json + JS/TS files	JS/TS	Yes
*.csproj	.NET	No
requirements.txt / pyproject.toml	Python	No
go.mod	Go	No

Phase 2: Delegate to Workers

CRITICAL: All delegations use Agent tool with subagent_type: "general-purpose" and isolation: "worktree" — each worker creates its own branch per shared/references/git_worktree_fallback.md.

Delegation Protocol

FOR each selected worker:
  Agent(description: "Modernize via ln-83X",
       prompt: "Execute modernization worker.

Step 1: Invoke worker:
  Skill(skill: \"ln-83X-{worker}\")

CONTEXT:
{delegationContext}",
       subagent_type: "general-purpose",
       isolation: "worktree")

Delegation Context

Field	Type	Description
projectPath	string	Absolute path to project
auditReport	string	Path to codebase_audit.md (if applicable)
targetModule	string	Target module path (if applicable)
options.runTests	bool	Run tests after modernization

Execution Order

Order	Worker	Reason
1	ln-831 (OSS replacer)	May add/remove packages, affecting bundle
2	ln-832 (bundle optimizer)	Runs AFTER package changes are settled

Rules:

Workers run sequentially — ln-831 package changes affect ln-832 baseline.
Dependent workers share branch: ln-832 launches in ln-831's branch so it sees OSS replacement changes.

Phase 3: Collect Results

Each worker produces an isolated branch. Coordinator aggregates branch reports.

Worker Branches

Worker	Branch Pattern	Contents
ln-831	`modernize/ln-831-{module}-{ts}`	OSS replacements
ln-832	`modernize/ln-832-bundle-{ts}`	Bundle optimizations

Result Schema

Field	Type	Description
worker	string	ln-831 or ln-832
status	enum	success, partial, failed
branch	string	Worker's result branch name
changes_applied	int	Number of kept changes
changes_discarded	int	Number of discarded attempts
details	object	Worker-specific report

Phase 4: Aggregate Reports

Each worker verified independently in its branch (tests, build run by worker itself). Coordinator does NOT rerun verification or revert worker changes.

On Failure

Branch with failing tests logged as "failed" in report
User reviews failed branch independently

Phase 5: Report Summary

Report Schema

Field	Description
input_source	Audit report or target module
workers_activated	Which workers ran
modules_replaced	OSS replacements applied (ln-831)
loc_removed	Custom code lines removed (ln-831)
bundle_reduction	Bundle size reduction in bytes/% (ln-832)
build_verified	PASSED or FAILED
per_worker[]	Individual worker reports

Configuration

Options:
  # Input
  audit_report: "docs/project/codebase_audit.md"
  target_module: ""

  # Workers
  enable_oss_replacer: true
  enable_bundle_optimizer: true

  # Verification
  run_tests: true
  run_build: true

  # Safety
  revert_on_build_failure: true

Error Handling

Recoverable Errors

Error	Recovery
ln-831 failure	Continue with ln-832
ln-832 failure	Report partial success (ln-831 results valid)
Build failure	Revert last worker, re-verify

Fatal Errors

Error	Action
No workers activated	Report "no modernization targets found"
All workers failed	Report failures, suggest manual review
Dirty git state	Block with "commit or stash changes first"

References

../ln-831-oss-replacer/SKILL.md
../ln-832-bundle-optimizer/SKILL.md
../ln-645-open-source-replacer/SKILL.md (audit companion)
shared/references/ci_tool_detection.md

Definition of Done

Input analyzed (audit report or target module)
Appropriate workers selected based on input and stack
Workers delegated with worktree isolation (isolation: "worktree", ln-831 before ln-832)
Each worker produces isolated branch, pushed to remote
Coordinator report aggregates per-worker results (branch, changes, status)

Phase 6: Meta-Analysis

MANDATORY READ: Load shared/references/meta_analysis_protocol.md

Skill type: optimization-coordinator. Run after all phases complete. Output to chat using the optimization-coordinator format.

Version: 1.0.0 Last Updated: 2026-03-08