Devonair
Use CasesguideNovember 7, 20256 min read

Automate Dead Code Removal Across Your Codebase

Find and remove unused code with AI automation. Learn how AI agents identify dead functions, unused exports, and abandoned features safely.

Dead code is the clutter of software development. Unused functions, orphaned exports, abandoned feature flags - they accumulate silently, making codebases harder to understand and maintain. Everyone agrees it should be cleaned up. Nobody wants to do it.

The fear is understandable. "What if something's actually using that?" is the question that keeps dead code alive. Manual dead code removal requires confidence that humans rarely have, especially in large codebases they didn't write.

AI agents can analyze entire codebases to verify what's truly dead, then remove it confidently.

How Dead Code Accumulates

Dead code enters codebases through predictable paths:

Feature removal: A feature gets deprecated, but only the UI is removed. Backend code, utilities, and tests linger.

Refactoring leftovers: Code gets restructured, but old implementations stay "just in case."

Defensive preservation: Functions are kept because "someone might need that later."

Copy-paste evolution: Utilities get copied and modified. The originals become unused.

Failed experiments: Prototype code that never shipped but never got deleted.

Over time, dead code creates confusion:

  • New developers waste time understanding code that doesn't matter
  • IDE autocomplete suggests unused functions
  • Refactoring tools process files that shouldn't exist
  • Test coverage metrics include untestable code
  • Build times include unnecessary files

What Counts as Dead Code

Not all unused code should be deleted. Understanding the types helps target cleanup:

Unreferenced Exports

Functions, classes, or variables exported but never imported anywhere:

@devonair identify all exports in /src with zero imports

Unreferenced Functions

Functions defined but never called:

@devonair identify all functions with zero call sites across the codebase

Unused Variables

Variables declared but never read:

@devonair identify unused variables in /src

Dead Branches

Code paths that can never execute:

@devonair identify unreachable code branches (conditions always true/false)

Abandoned Feature Flags

Feature flags that are always on or always off:

@devonair identify feature flags that have been consistently true/false for the past month

Commented Code

Code blocks commented out that should either be deleted or uncommented:

@devonair identify large commented-out code blocks

Safe Dead Code Removal

The key word is "safe." Dead code removal should never break working code.

Start with Analysis

Before removing anything, inventory what you have:

@devonair analyze /src and report all potentially dead code with confidence scores

The agent categorizes findings:

  • High confidence: No references found anywhere
  • Medium confidence: References exist but may be dead themselves
  • Low confidence: Dynamic usage possible

Remove High-Confidence Dead Code

Start with code that's definitely unused:

@devonair remove all exports with zero imports and no dynamic references

@devonair remove all private functions with zero call sites

Handle Medium-Confidence Carefully

Code with indirect references needs review:

@devonair remove dead code chains - functions only called by other dead functions

The agent traces reference chains to find entire dead subsystems.

Preserve Low-Confidence Code

Dynamic code patterns need human judgment:

// This might look dead but could be called dynamically
export function handleAction(action) { ... }

// Elsewhere
actions[actionType](); // Dynamic call

The agent flags these for review rather than automatic removal.

Removal Patterns

The Surgical Approach

Remove specific categories of dead code:

@devonair remove all unused imports in /src

@devonair remove all private functions with no callers in /src/utils

@devonair remove all empty files in /src

Small, targeted removals are easy to review and low-risk.

The Module Approach

Clean up entire modules at once:

@devonair identify and remove all dead code in /src/legacy-auth

When refactoring or removing features, clean up the whole area.

The Confidence-Based Approach

Remove by confidence level:

@devonair remove dead code with >95% confidence

Then manually review the remaining lower-confidence cases.

Preserving Intentionally Unused Code

Some code should exist even without current references:

Public APIs

@devonair remove dead code but preserve all public API exports

Public APIs might be used by external consumers you can't analyze.

Future Features

@devonair remove dead code but preserve files marked with @future or TODO

Code staged for upcoming features should be explicitly marked.

Documentation Examples

@devonair remove dead code but preserve functions in /src/examples

Example code exists for documentation, not execution.

Testing After Removal

Verify that removal didn't break anything:

@devonair remove dead code and run full test suite

@devonair remove dead code, build the project, and run type checker

If tests fail, the code wasn't actually dead - revert and investigate.

Scheduling Regular Cleanup

Dead code accumulates continuously. Clean up continuously:

@devonair schedule weekly: remove unused imports across /src

@devonair schedule monthly: identify and remove dead exports

@devonair schedule quarterly: comprehensive dead code analysis and removal

Measuring Dead Code

Track your progress:

@devonair report on dead code: total files, functions, and lines that appear unused

Set targets:

  • Zero unused imports (easy to achieve)
  • Less than N unused exports (realistic target)
  • All dead code reviewed within 30 days of identification

Common Dead Code Patterns

The Deprecated Module

@devonair identify modules that were replaced and remove the old versions

When you build a v2, remove the v1.

The Utility Graveyard

@devonair analyze /src/utils for functions with zero usage

Utility folders accumulate functions nobody uses.

The Test Double

@devonair identify mock/stub files with no corresponding tests

Test helpers outlive the tests that needed them.

The Configuration Ghost

@devonair identify configuration options that are never read

Config objects grow features that get removed without cleanup.

Getting Started

Start with the safest, most obvious dead code:

@devonair remove all unused imports across /src

This is risk-free and often removes hundreds of lines immediately.

Then escalate:

@devonair identify private functions with zero call sites

Review the list. Remove what's clearly dead. Investigate what's unclear.

A cleaner codebase is a faster codebase - for humans and machines alike.

FAQ

How do I know if code is really dead?

The agent analyzes static references throughout the codebase. It flags dynamic calls, reflection, and external API usage as uncertain. High-confidence results are safe to remove; lower-confidence results need human review.

What if dead code removal breaks something?

Your tests should catch issues before merge. If something breaks in production, the code wasn't actually dead - it was called dynamically or externally. Revert and add documentation about why the code exists.

Should I delete or comment out dead code?

Delete it. Version control means you can always recover it. Commented code is just clutter that makes active code harder to read.

How often should I clean up dead code?

Schedule regular cleanup - weekly for imports, monthly for functions, quarterly for comprehensive analysis. Continuous small cleanups beat occasional large ones.

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