# Gap Analysis

*Audit taken early 2026 — preserved as-is for historical reference. See the [Status update](#status-update--july-2026) at the bottom for what has changed since.*

Comprehensive audit of what TrickBook is missing compared to production-grade engineering standards. Based on a full scan of both the TrickList mobile app and Backend API repositories.

## Summary

**98+ mobile source files and 24 backend route files with zero tests, zero linting, and zero automated quality gates.**

The app works and is live on the App Store, but it's running without a safety net. Any of the issues below could cause production incidents that are invisible until a user reports them (or leaves a 1-star review).

## Critical Gaps

### 1. No Linting or Formatting

**Both repos.** No ESLint, no Prettier, no Biome, nothing. Code style is inconsistent, unused variables go unnoticed, and potential bugs (like accidental `=` in conditionals) have no automated detection.

**Fix:** [Biome setup](/docs/engineering/linting-formatting) - single tool for both linting and formatting, 30 minutes to set up.

### 2. Zero Test Coverage

**Both repos.** Not a single test file exists across the entire project. The auth flow, API client, trick list CRUD, payment processing - all untested.

| Repo | Source Files | Test Files |
|------|-------------|------------|
| TrickList | 98+ (.ts/.tsx) | 0 |
| Backend | 24 route files, 6 middleware, 3 services | 0 |

**Fix:** [Testing strategy](/docs/engineering/testing) - start with the 10 highest-risk tests.

### 3. No Pre-commit Hooks

**Both repos.** Nothing prevents committing broken code, unformatted files, or files with lint errors. Bad code goes straight into git history.

**Fix:** [Husky + lint-staged](/docs/engineering/pre-commit-hooks) - 30 minutes to set up.

### 4. No Error Boundary (Mobile)

One uncaught error in any React component crashes the entire app with a white screen. No recovery, no error message, no crash report.

**Fix:** [ErrorBoundary component](/docs/engineering/error-handling) - 1 hour.

### 5. No Error Tracking

**Both repos.** No Sentry, no Crashlytics, nothing. When the app crashes in production or the API throws 500s, nobody knows unless a user complains.

**Fix:** [Sentry integration](/docs/engineering/error-handling#sentry-integration) - 1 hour per repo.

### 6. No CI/CD Quality Gates

**Both repos.** No GitHub Actions, no automated checks on PRs. The mobile app is built manually via EAS CLI. The backend is deployed manually.

**Fix:** [CI/CD pipeline](/docs/deployment/ci-cd) - 1 hour to set up.

## High Priority Gaps

### 7. console.log Everywhere

| Repo | console.log/error Count | Files Affected |
|------|------------------------|----------------|
| TrickList | 54+ | 14 files |
| Backend | 410+ | 44 files |

Some logs include PII (emails, user IDs). In production, there's no way to filter, search, or alert on these.

**Fix:** [Structured logging](/docs/engineering/logging)

### 8. Dead Dependencies (Mobile)

6 packages installed but never imported:

| Package | Version | Imports Found |
|---------|---------|:---:|
| `formik` | ^2.2.9 | 0 |
| `yup` | ^0.32.11 | 0 |
| `react-hook-form` | ^7.71.1 | 0 |
| `@hookform/resolvers` | ^5.2.2 | 0 |
| `jotai` | ^1.11.2 | 0 |
| `apisauce` | ^1.1.1 | 0 |

These add unnecessary bundle size and confusion. Zustand is the only state manager actually used. No form library is actually used (forms use manual `useState`).

**Fix:** [Remove dead dependencies](/docs/engineering/code-quality#dead-dependencies)

### 9. No API Response Validation (Mobile)

Zod is installed but only used in 2 files. The other 11 API service files return raw `response.json()` with TypeScript types that provide zero runtime safety.

If the API returns unexpected data, the app crashes at the point of use (deep in a component render) instead of at the API boundary where it's catchable.

**Fix:** [Zod schemas for API responses](/docs/engineering/code-quality#api-response-validation)

### 10. No .env.example (Both Repos)

The Backend requires 23+ environment variables. The mobile app needs at least 3. Neither repo has a `.env.example` template. After a fresh clone, there's no way to know what's needed without reading every file that references `process.env`.

**Fix:** [Create .env.example files](/docs/engineering/code-quality#envexample-files)

### 11. No Input Sanitization (Backend)

No `express-mongo-sanitize` or equivalent. The API is vulnerable to NoSQL injection:

```json
// This bypasses authentication without sanitization
POST /api/auth
{ "email": "admin@test.com", "password": { "$gt": "" } }
```

**Fix:** [Add express-mongo-sanitize](/docs/engineering/code-quality#backend-input-sanitization)

### 12. No Global Error Handler (Backend)

Each of the 24 route files handles errors independently with try/catch. There's no centralized error handler middleware. Error responses are inconsistent across endpoints.

**Fix:** [Global error handler](/docs/engineering/error-handling#backend-global-error-handler)

## Medium Priority Gaps

### 13. MongoDB Connection Anti-Pattern (Backend)

Every route file creates its own `MongoClient.connect()`. That's 24 separate database connections instead of 1 shared pool. This wastes resources and can hit MongoDB's connection limit.

**Fix:** Centralize to a single connection pool (documented in [Security Fixes](/docs/roadmap/security-fixes#medium-centralize-database-connection)).

### 14. Mixed MongoDB Drivers (Backend)

Both `mongodb` (native driver, v4.13.0) and `mongoose` (ODM, v8.15.1) are installed and used. This means two connection pools, two query syntaxes, and two mental models.

**Recommendation:** Pick one. Since routes already use the native driver extensively, either commit to `mongodb` or fully migrate to Mongoose.

### 15. No Health Check Endpoint (Backend)

No `/health` or `/status` endpoint. Load balancers, uptime monitors, and Kubernetes probes have nothing to ping.

**Fix:** [Health check endpoint](/docs/engineering/error-handling#backend-health-check-endpoint)

### 16. No Graceful Shutdown (Backend)

No `SIGTERM`/`SIGINT` handlers. When the server restarts (deploy, crash, scaling), active WebSocket connections are dropped immediately and in-flight database operations may be interrupted.

**Fix:** [Graceful shutdown](/docs/engineering/error-handling#backend-graceful-shutdown)

### 17. No Docker (Backend)

No Dockerfile, no docker-compose. Deployments depend on the hosting environment having the right Node.js version and system dependencies. Not reproducible.

**Fix:** [Dockerize the backend](/docs/engineering/code-quality#backend-dockerize)

### 18. Outdated Backend Dependencies

| Package | Current | Latest | Risk |
|---------|---------|--------|------|
| Node.js | 12.6.x | 20 LTS | **EOL since April 2022** |
| helmet | 3.22.0 | 8.x | Missing security headers |
| joi | 14.3.1 | 17.x | Deprecated API (`Joi.validate()`) |
| jsonwebtoken | 8.5.1 | 9.x | Known vulnerabilities |
| aws-sdk | 2.x | 3.x | Deprecated, v3 already installed alongside |

### 19. Old AWS SDK v2 Still Installed (Backend)

Both `aws-sdk` (v2, deprecated) and `@aws-sdk/client-s3` (v3) are in `package.json`. The v2 SDK is 50MB+ and deprecated. Remove it if all usage has migrated to v3.

## Lower Priority

### 20. TypeScript Strictness (Mobile)

`tsconfig.json` has `strict: true` but is missing:
- `noUncheckedIndexedAccess` - forces handling `undefined` on array/object access
- `noImplicitOverride` - requires explicit `override` keyword
- `forceConsistentCasingInFileNames` - prevents import casing bugs

### 21. File Size (Mobile)

`src/lib/api/feed.ts` is 538 lines. Consider splitting into `feed-posts.ts`, `feed-reactions.ts`, `feed-comments.ts`.

### 22. Backend README

References outdated information. Needs a rewrite to match current architecture.

## Implementation Priority

| # | Task | Effort | Impact | Repo |
|---|------|--------|--------|------|
| 1 | Add Biome (lint + format) | 30 min | High | Both |
| 2 | Add pre-commit hooks | 30 min | High | Both |
| 3 | Add error boundary | 1 hour | High | Mobile |
| 4 | Add Sentry | 1 hour | High | Both |
| 5 | Write first 10 tests | Half day | High | Both |
| 6 | Add CI/CD pipeline | 1 hour | High | Both |
| 7 | Remove dead dependencies | 30 min | Medium | Mobile |
| 8 | Add structured logging | 2 hours | Medium | Both |
| 9 | Add .env.example | 15 min | Medium | Both |
| 10 | Add input sanitization | 30 min | Medium | Backend |
| 11 | Add global error handler | 1 hour | Medium | Backend |
| 12 | Add health check | 30 min | Medium | Backend |
| 13 | Add graceful shutdown | 30 min | Medium | Backend |
| 14 | Consolidate MongoDB driver | Half day | Medium | Backend |
| 15 | Add Zod API validation | 1 day | Medium | Mobile |
| 16 | Dockerize backend | 1 hour | Low | Backend |
| 17 | Upgrade Node.js | Half day | Low (security: High) | Backend |

## Status update — July 2026

Status: **Partially resolved** · July 2026

Several of the gaps above have been closed since this audit was taken:

| Gap | Status | Notes |
|-----|--------|-------|
| No `.env.example` (Backend) | ✅ Resolved | `repos/Backend/.env.example` documents all required variables with placeholders |
| No linting/formatting | ✅ Resolved | Biome set up across mobile, backend, and docs repos |
| No pre-commit hooks | ✅ Resolved | Husky + lint-staged in place across repos |
| No CI/CD quality gates | ✅ Resolved | GitHub Actions CI running on mobile, backend, and docs |
| Android distribution | ✅ Resolved | Google Play closed alpha shipped |
| Outdated Node.js (Backend) | ✅ Resolved | Production backend upgraded to Node 20 |
| No rate limiting | ⚠️ Partial | Applied to auth/registration endpoints only; broader API coverage still pending |
| No error tracking (Sentry) | 📋 Pending | Still not integrated in either repo |
| Zero test coverage | 📋 Pending | Still no test files in either repo |

Separately, a full-app **UX audit** — covering both web and mobile, focused on intuitiveness and user value, with usage-analytics instrumentation to measure how features are actually used — is now planned as part of the [current priorities](/docs/roadmap/priorities). That effort is a different lens from this document: this gap analysis measures engineering rigor (tests, tooling, safety nets), while the UX audit measures whether the product experience itself is working for users.