# Code Pruning > Dead code detection strategies, safe removal processes, dependency pruning, and bloat metrics for systematically reducing codebase dead weight. Use when evaluating codebase health during architecture-audit, performing cleanup during cook, reviewing unused dependencies, removing commented-out code, or measuring code bloat. Use when this capability is needed. - Skill: `tomevault-io/code-pruning` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/code-pruning` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/code-pruning/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Security - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/code-pruning --- # Code Pruning ## Pruning Checklist - [ ] Static analysis tools run for all project languages - [ ] SCARF phases followed (Survey → Classify → Announce → Remove → Follow-up) - [ ] Each removal verified by test suite - [ ] Dependency manifest audited for unused packages - [ ] Commented-out code deleted (version control remembers) - [ ] Bloat metrics captured before and after ## Detection Approaches | Approach | How It Works | Confidence | Limitation | |----------|-------------|------------|------------| | **Static analysis** | Parse AST, trace references | High for unused exports/functions | Misses dynamic dispatch, reflection | | **Dynamic analysis** | Runtime instrumentation, coverage | High for executed paths | Misses rarely-used paths (disaster recovery, seasonal) | | **Combined (SCARF)** | Static + dynamic + team review | Highest | Requires team coordination | | **Manual review** | Human inspection, git blame | Variable | Doesn't scale; subjective | ## SCARF Pattern (from Meta) | Phase | Action | Checkpoint | |-------|--------|------------| | **S**urvey | Run static analysis tools; identify candidates | Candidate list generated | | **C**lassify | Categorize each: dead, dormant, speculative, deprecated | Each candidate classified | | **A**nnounce | Deprecation warnings; notify stakeholders | Team aware of pending removals | | **R**emove | Delete with tests verifying no breakage | All tests pass after removal | | **F**ollow-up | Monitor production for regressions; verify no side effects | No production issues after 1 week | **For smaller teams:** Compress Announce into a PR description or commit message. The key phases are Survey, Classify, and Remove-with-tests. ## Language-Specific Tools (current as of Feb 2026) | Language | Tool | Notes | |----------|------|-------| | JS/TS | **Knip** | Supersedes ts-prune; handles re-exports, dependencies, and unused files | | JS/TS | depcheck | Focused on unused npm dependencies | | Python | **Vulture** | AST-based dead code detection; configure `--min-confidence 80` | | Python | autoflake | Removes unused imports and variables | | Java | PMD | Static analysis rules for unused code | | Go | **deadcode** | Official Go team tool (1.22+); superior to `unused` | | Multi | SonarQube | Cross-language; includes unused code rules | ## Safe Removal Process (6 Steps) 1. **Identify** — Run static analysis; flag zero-reference code 2. **Verify with dynamic data** — Check code coverage, production logs, feature flags 3. **Deprecate** — Add deprecation warnings; set removal date 4. **Delete** — Remove code in atomic, single-concern commits 5. **Test** — Full test suite passes; no integration regressions 6. **Audit** — Post-removal monitoring for 1 week; check error rates ## Dependency Pruning ### Common False Positives | False Positive | How to Verify | |----------------|---------------| | Peer dependency | Check if required by another installed package | | CLI tool | Check npm scripts, Makefile, CI config | | Plugin/loader | Check config files (webpack, babel, pytest, etc.) | | Type-only import | Check `.d.ts` files and type annotations | ## Bloat Metrics | Indicator | Healthy | Warning | Critical | |-----------|---------|---------|----------| | Unreachable code ratio | <5% | 5-15% | >15% | | Unused dependency count | 0-2 | 3-5 | >5 | | Commented-out code blocks | 0 | 1-5 | >5 | | Single-implementation interfaces | <3 | 3-10 | >10 | ## Decision Tables ### "How confident am I that this code is dead?" | Evidence | Confidence | Action | |----------|-----------|--------| | Zero static references + zero runtime coverage | High | Delete (with tests) | | Zero static refs but in error/recovery path | Medium | Verify with team before deleting | | Referenced only by tests | Medium | Delete code and tests together | | Referenced by commented-out code only | High | Delete both | | Dynamic dispatch possible (reflection, eval) | Low | Instrument before deleting | ### "Should I prune this dependency?" | Signal | Action | |--------|--------| | Zero imports in source code | Remove (check for false positives first) | | Only in devDependencies, not used in scripts | Remove | | Imported but functionality is unused | Replace with lighter alternative or remove | | Peer dependency of another package | Keep — removing breaks the dependent | | Last updated >2 years, no maintained fork | Plan migration to maintained alternative | --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/smileynet) — claim your Tome and manage your conversions.