# Dry > Use this skill to find and eliminate duplication across your codebase — UI components, database schema, and workflow logic. Also use when the codebase feels bloated, features take longer to build, changes break in unexpected places, or after significant AI-assisted development. Covers code deduplication, component reuse, database normalization, and modular architecture. - **Type:** Skill - **Install:** `agentstack add skill-whawkinsiv-solo-founder-skills-dry` - **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior - **Seller:** [whawkinsiv](https://agentstack.voostack.com/s/whawkinsiv) - **Installs:** 0 - **Category:** [Databases](https://agentstack.voostack.com/c/databases) - **Latest version:** 0.1.0 - **License:** MIT - **Upstream author:** [whawkinsiv](https://github.com/whawkinsiv) - **Source:** https://github.com/whawkinsiv/solo-founder-skills/tree/main/skills/dry ## Install ```sh agentstack add skill-whawkinsiv-solo-founder-skills-dry ``` Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent. ## About # Don't Repeat Yourself Find and eliminate duplication across your codebase. Every duplicate is a future bug — when you fix something in one place but forget the copy, users hit the unfixed version. **This skill audits and refactors.** For building features, use **build**. For general performance optimization, use **optimize**. For database schema design from scratch, use **database**. For UI component selection, use **ui-patterns**. ## Two Modes | Mode | When | Scope | Time | |------|------|-------|------| | **Quick scan** | After building a feature, or on request | Recent changes vs. existing codebase | 2-5 minutes | | **Deep audit** | Codebase feels bloated, periodic cleanup | Entire codebase, all three domains | 15-30 minutes | **Choose quick scan** after implementing features, adding new pages, or building new API endpoints. **Choose deep audit** when the codebase has grown through many rounds of AI-assisted iteration, or quarterly as hygiene. --- ## Quick Scan Workflow Run this after building or modifying a feature. ``` Quick DRY scan: - [ ] Identify what was just built or changed - [ ] Search for similar patterns in existing codebase - [ ] Flag any duplication with specific file locations - [ ] Refactor: extract shared code, reuse existing components - [ ] Verify nothing broke after refactoring ``` ### Process 1. **Identify the change** — What files were just created or modified? 2. **Search for siblings** — For each new component, function, or query: does something similar already exist? 3. **Decide: reuse or extract** — If a near-duplicate exists, reuse it. If two things are now similar, extract a shared version. 4. **Refactor** — Make the change, run build and tests. ### What to Search For - New component created → search for components with similar props, layout, or purpose - New utility function → search for functions with similar signatures or logic - New API endpoint → search for endpoints with similar query patterns or response shapes - New database query → search for queries hitting the same tables with similar conditions --- ## Deep Audit Workflow Run this for comprehensive deduplication across the full codebase. ``` Deep DRY audit: - [ ] Audit UI components for duplication - [ ] Audit database schema for normalization issues - [ ] Audit workflow logic for duplicate functions and patterns - [ ] Generate findings with specific refactoring actions - [ ] Apply fixes domain by domain, testing after each ``` See [AUDIT-CHECKLIST.md](AUDIT-CHECKLIST.md) for detailed search patterns and refactoring recipes per domain. --- ## Domain 1: UI Components ### What to Find - **Near-duplicate components** — Two card components, two modal wrappers, two form layouts with slight differences - **Repeated inline styles** — Same padding, colors, or layout CSS copied across components instead of using shared tokens or classes - **Same-purpose components** — `UserList` and `MemberList` that do essentially the same thing with different prop names - **Reimplemented patterns** — Custom dropdown when the component library already has one ### How to Fix 1. **Identical components** → Delete one, update imports to point to the survivor 2. **Near-duplicates** → Extract a shared component with props for the differences 3. **Repeated styles** → Extract into shared CSS classes, design tokens, or a utility class 4. **Reimplemented patterns** → Replace with the component library version ### AI-Tool-Specific Patterns | Tool | Common Duplication | Why | |------|-------------------|-----| | Lovable | Each prompt creates new Card/Button/Modal variants | Lovable doesn't reference existing components by default | | Replit | Inline styles duplicated across pages | Fast iteration favors copy-paste | | Cursor | Similar components in different feature folders | File-scoped context misses cross-feature reuse | | Claude Code | Utility components recreated in new feature branches | Context window doesn't always include existing shared components | **Tell AI (for other tools):** ``` Search my codebase for duplicate UI components: - Find components with similar JSX structure or props - Find repeated inline styles or CSS classes - Find components that render the same kind of data differently For each duplicate: show both versions side-by-side and propose a single shared component. ``` --- ## Domain 2: Database Schema ### What to Find - **Denormalized data** — User's email stored in both `users` table and `orders` table instead of joining - **Missing foreign keys** — IDs stored as plain integers/strings without proper references - **Repeated column groups** — `created_at`, `updated_at`, `created_by` defined inconsistently across tables - **Enum values in columns** — Status strings like `'active'`, `'inactive'` repeated instead of using a lookup table - **Duplicate lookup data** — Category names stored as strings in every row instead of referencing a categories table ### How to Fix 1. **Denormalized data** → Remove the duplicate column, add a JOIN where needed 2. **Missing foreign keys** → Add proper FK constraints with ON DELETE behavior 3. **Repeated column groups** → Standardize naming and types across all tables 4. **String enums** → Create a lookup table or use a database enum type (for values that won't change) 5. **Duplicate lookup data** → Extract into a reference table, replace with foreign key ### Red Flags in AI-Generated Schemas AI tools often create self-contained tables per feature. Watch for: - A `projects` table with `owner_name` and `owner_email` instead of `owner_id` referencing `users` - An `invoices` table with `customer_name`, `customer_email`, `customer_address` instead of `customer_id` - Multiple tables with their own `status` VARCHAR column using the same string values **Tell AI (for other tools):** ``` Audit my database schema for normalization issues: - Find columns that store data already available in another table - Find ID columns without foreign key constraints - Find string columns that should be lookup tables - Find inconsistent column naming across tables For each: explain the problem and write the migration to fix it. ``` --- ## Domain 3: Workflow Logic ### What to Find - **Duplicate utility functions** — Two `formatDate()` functions in different files - **Repeated API patterns** — Same fetch-try-catch-error-handle boilerplate across endpoints - **Copy-pasted validation** — Email validation logic in signup, settings, and invite flows - **Duplicate business logic** — Price calculation in checkout, invoice generation, and dashboard - **Repeated data transforms** — Same array mapping/filtering logic in multiple components ### How to Fix 1. **Duplicate utilities** → Keep one, move to a shared `utils/` or `lib/` directory, update all imports 2. **API boilerplate** → Extract a shared API client or wrapper function 3. **Repeated validation** → Create a shared validation module (e.g., `lib/validators.ts`) 4. **Business logic** → Extract into a service or domain module (e.g., `lib/pricing.ts`) 5. **Data transforms** → Extract into named functions near the data type they operate on ### Search Strategy ``` Find duplicate logic: 1. Search for functions with identical or near-identical bodies 2. Search for repeated import patterns (same 3+ imports in multiple files) 3. Search for similar try/catch blocks around API calls 4. Search for the same regex or validation pattern in multiple files 5. Search for string literals used in more than 2 files (often config that should be a constant) ``` **Tell AI (for other tools):** ``` Audit my codebase for duplicate workflow logic: - Find functions with similar names or identical logic in different files - Find repeated error handling patterns - Find validation logic that appears in more than one place - Find business calculations done in more than one place For each: show all locations and propose a single shared implementation. ``` --- ## What NOT to Deduplicate Not all duplication is bad. Don't over-abstract. | Leave It Alone | Why | |---------------|-----| | Two functions that look similar but serve different business purposes | They'll diverge. Premature abstraction creates coupling. | | Test setup code that repeats across test files | Test readability matters more than test DRYness. | | Simple one-liners used twice | Extracting adds indirection without meaningful reuse. | | Code that's similar today but will evolve differently | Shared abstractions should reflect stable, shared concepts. | | Configuration that's the same across environments by coincidence | Config should be explicit per environment, not shared. | **Rule of three:** If something appears in 3+ places, extract it. If it's only in 2 places, wait until the third occurrence to confirm it's a real pattern, not coincidence. --- ## Common Mistakes | Mistake | Fix | |---------|-----| | Creating a `utils.ts` mega-file | Group by domain: `lib/pricing.ts`, `lib/validation.ts`, `lib/formatting.ts` | | Abstracting before the pattern stabilizes | Wait for 3+ occurrences. Two similar things might diverge. | | Breaking working code to "clean it up" | Run build and tests after every refactoring step | | Over-parameterizing a shared component | If a component needs 10 props to handle all cases, it's doing too much | | Deduplicating across feature boundaries prematurely | Features that share code today might need to diverge tomorrow | --- ## Success Looks Like After a DRY audit, you should see: - Each UI component exists once with clear props for variation - Database tables reference each other via foreign keys instead of duplicating data - Shared logic lives in clearly named modules under `lib/` or `utils/` - No function body is copy-pasted across files - New features can reuse existing components and utilities instead of recreating them --- ## Related Skills - **optimize** — Performance and cleanup (speed, dependencies, dead code) - **database** — Schema design, RLS, migrations, query patterns - **ui-patterns** — Component selection, state matrix, page composition - **build** — Feature development workflow and AI tool prompting - **debug** — When deduplication breaks something ## Source & license This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code. - **Author:** [whawkinsiv](https://github.com/whawkinsiv) - **Source:** [whawkinsiv/solo-founder-skills](https://github.com/whawkinsiv/solo-founder-skills) - **License:** MIT Install and usage instructions live in the source repository linked above. ## Pricing - **Free** — Free ## Security capabilities Automated source analysis of v0.1.0 — what this tool can access: - **Network access:** no - **Filesystem access:** no - **Shell / process execution:** no - **Environment & secrets:** no - **Dynamic code execution:** no *"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.* ## Versions - **0.1.0** — security scan: passed — Imported from the upstream source. ## Links - Listing page: https://agentstack.voostack.com/l/skill-whawkinsiv-solo-founder-skills-dry - Seller: https://agentstack.voostack.com/s/whawkinsiv - Browse the marketplace: https://agentstack.voostack.com/browse --- Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.