Freelance Backend/API Engineer — MVP for React Native App

Freelance Backend/API Engineer — MVP for React Native App

Contract: 6–10 weeks (extendable)
Schedule: Flexible; 2–4 hrs overlap with GMT+5:30
Compensation: LKR 4,500–12,000/hour (or milestone-based)
Start: Immediate

About the Project

We’re shipping a cross-platform MVP in React Native. You’ll own the backend architecture and API layer end-to-end: data model, auth, core endpoints, observability, deployments, and a smooth handoff to mobile.

Responsibilities

• Design scalable REST APIs (OpenAPI/Swagger) with clean versioning.

• Implement Auth (JWT/OAuth), RBAC, rate limiting, CORS, input validation.

• Model relational data (PostgreSQL/MySQL), write performant queries & migrations.

• Build core features: profiles, search/filter, lists & detail, forms/validation, notifications hooks.

• Integrate payments (Stripe/PayHere), email/SMS, file storage (S3/DO Spaces).

• Add observability: structured logs, metrics, error tracking (Sentry) and basic dashboards.

• Ship CI/CD (GitHub Actions) and containerized deploys (Docker + Nginx).

• Provide docs (API spec, Postman collection, env templates) and a clean handover.

Preferred Stack

• Node.js with NestJS or Express (+ TypeScript)

• ORM: Prisma/TypeORM, Zod/Joi for validation

• DB: PostgreSQL or MySQL

• Cache/Queues: Redis, bullmq (if needed)

• Storage: DigitalOcean Spaces / AWS S3

• Tests: Jest, supertest

• Infra: Docker, Nginx, GitHub Actions, any of DO/AWS/Vercel/Render

Laravel experts are welcome too (Laravel + Sanctum/Passport, Eloquent, Horizon/queues).

MVP Milestones (example)

1. Week 1: Architecture doc, ERD, endpoint list, repo scaffold, auth + users.

2. Week 2–3: Core entities & CRUD, search/pagination, validation, OpenAPI docs.

3. Week 4: Integrations (payments, email/SMS, storage), webhooks, audit logs.

4. Week 5: Perf pass (N+1, indexes, caching), security hardening, basic analytics.

5. Week 6: Staging deploy, monitoring, load test, final docs & handover.

What We’re Looking For

• 3+ years building production APIs.

• Solid SQL design & performance tuning.

• Proven security awareness (OWASP, secrets, least privilege).

• Clear communication and crisp PRs.

Nice-to-Have

• WebSockets/Server-Sent Events for live updates.

• Feature flags/remote config, multi-tenancy basics.

• Experience with app store backends or subscription flows.

Budget

• Hourly: LKR 4,500–12,000 (experience & speed).

• Fixed: Propose milestone quotes with assumptions & risks.

How to Apply (include all 6)

1. Short intro + weekly availability.

2. GitHub/portfolio + 2 live APIs you built (or public docs).

3. A recent OpenAPI/Swagger link/file.

4. One paragraph on a perf/security win you shipped.

5. Preferred stack (Nest/Express/Laravel) and why.

6. Your best hourly rate and milestone quote for the scope above.

Apply on DevJobs.lk