codebase-refactoring

코드베이스 안전 리팩토링

Systematic, safe refactoring — not big-bang rewrites. One change at a time, verified between each step.

Core Principles

1. Map before you cut. Never delete or move code without tracing its import/reference graph first.
2. Smallest safe step first. Dead config removal → orphan file deletion → data consolidation → structural change. Each step must be independently reversible.
3. Verify between each change. With a running dev server, confirm HTTP 200 before the next edit.
4. Master data pattern. When the same data exists in 2+ places (frontend constants, backend arrays, separate workers), extract to a JSON file and have every consumer import it. JSON is universally readable by JS and TS.
5. No "while I'm here" expansions. One class of change per session.

Step-by-step Workflow

Phase 1 — Discovery

# 1. Map all files under the project root (exclude node_modules, build artifacts)
find . -type f -name '*.ts' -o -name '*.js' -o -name '*.html' -o -name '*.css' -o -name '*.sql' | grep -v node_modules | sort

# 2. Map all import/reference edges
grep -rn "^import\|from.*['\"]" --include='*.ts' --include='*.js' . | grep -v node_modules | sort

# 3. Identify dead code by reference counting
# If a file/export has zero import references, it's a candidate for deletion
grep -rn "export const\|export function\|export class" --include='*.ts' . | grep -v node_modules
# Cross-reference each export against import statements in other files

Phase 2 — Dead Code Removal (Risk: 🟢 Zero)

Safe to delete when:

• No import or require references from any other file
• No <script src="..."> or <link href="..."> from any HTML
• Config keys that are defined but never read (grep for the read-side)

Verification command:

# After deletion, confirm 404 on deleted paths and 200 on everything else
curl -s -o /dev/null -w "%{http_code}" "http://localhost:PORT/path/to/deleted/file"

Phase 2.5 — Complete Feature Removal (Risk: 🟢 Low–🟡 Medium)