Code Impact Analyzer

Developer-first CLI to predict blast radius from real diffs or simulated file changes.

It builds a dependency graph, traverses reverse dependencies, scores impacted files, and explains why each file is affected.

Features

• Diff-aware analysis (HEAD~1, staged, commit range)
• Simulation mode before making changes (check)
• Impact scoring with risk levels (HIGH, MEDIUM, LOW)
• Explainability (--why) and source-line insights (--code)
• Policy gates for CI (criticalPaths, risk threshold, owners)
• Incremental cache for faster repeated runs
• Forecast/validation loop with precision/recall/F1 metrics

Install

npm install

Quickstart

# Simulate impact before editing code
impact-analyzer check src/auth.ts --why

# Analyze actual repo changes
impact-analyzer analyze --staged --why

# Export machine-readable artifacts
impact-analyzer analyze --export output --output both

Commands

impact-analyzer analyze [--commit <ref> | --staged] [options]
impact-analyzer check <file...> [--targets <csv>] [options]
impact-analyzer graph [file] [--depth <n>]
impact-analyzer focus <file>
impact-analyzer interactive
impact-analyzer metrics

Common options:

• --output cli|json|both
• --report-file <path>
• --export [dir]
• --why
• --code
• --depth <n> / --max-depth <n>
• --risk HIGH|MEDIUM|LOW
• --fast
• --record-forecast
• --validate-latest
• --ci
• --ci-threshold <risk>
• --no-cache
• --cache-file <path>

Config

Create impact.config.json in target repo root:

{
  "ignore": ["node_modules", ".git", "tests"],
  "extensions": [".js", ".ts", ".jsx", ".tsx"],
  "cache": {
    "enabled": true,
    "file": ".impact-cache.json"
  },
  "policies": {
    "criticalPaths": ["src/payments/**", "src/auth/**"],
    "owners": {
      "src/auth/**": "@security-team",
      "src/**": "@app-team"
    },
    "ci": {
      "failOnRisk": "HIGH",
      "failOnCritical": true
    }
  },
  "validation": {
    "forecastsFile": ".impact-forecasts.jsonl",
    "metricsFile": ".impact-validation.jsonl"
  }
}

Create Repo and Push

cd /home/anj/impact-analyzer
git init
git add .
git commit -m "feat: production-ready code impact analyzer"
git branch -M main
git remote add origin <YOUR_GITHUB_REPO_URL>
git push -u origin main

Deployment

CI

/.github/workflows/ci.yml runs:

• dependency install
• syntax check
• smoke test
• package dry-run

NPM Publish

/.github/workflows/publish-npm.yml publishes on GitHub Release or manual dispatch.

Required GitHub repo secret:

• NPM_TOKEN (from npm access token)

Optional release flow:

npm version patch
git push --follow-tags
# create GitHub Release for the new tag

Architecture

• src/cli: command orchestration
• src/git: git integration
• src/scanner: file discovery
• src/resolution: ts/js alias + workspace resolver
• src/parser: AST-first dependency extraction
• src/cache: incremental parse cache
• src/graph: dependency and reverse graph
• src/analysis: impact traversal + scoring
• src/policy: ownership and CI policy evaluation
• src/metrics: forecast validation metrics
• src/output: CLI and JSON formatting

License

MIT