MERN developer portfolio
Freelance MERN stack developer shipping full-stack JavaScript end-to-end: MongoDB and Postgres for data, Express and Next.js route handlers for the API, React on the frontend, Node.js everywhere. TypeScript end-to-end, REST or RPC depending on the surface, and the operational discipline to keep your database from melting under load.
- MongoDB schema design, indexing, and aggregation pipelines
- Postgres + Supabase for relational and realtime workloads
- Express, Fastify, and Next.js route handlers
- REST API design with proper auth, pagination, and rate limits
- Authentication: JWT, session cookies, OAuth, magic links
- File storage (S3, Supabase Storage) and background jobs
- Stripe billing integration with webhooks and subscription state
- Production observability: logs, traces, error reporting, uptime
Shipped work for the same brief.
- 2025CVLeap AI — Full-stack SaaS in 8 weeksEnd-to-end SaaS: React frontend, server actions and route handlers for the API, Supabase Postgres for data, OpenAI integration, PDF generation pipeline, billing, and admin panel.Next.jsTypeScriptSupabasePostgresOpenAI
- 2026Phone Assistant — Voice agent with Node backendNode.js mediator service between Twilio voice and OpenAI Realtime, Postgres for call state and routing rules, Next.js dashboard for ops. Built for sub-second turn latency at scale.Node.jsPostgresTwilioNext.js
- 2025Sysmind Melp — Realtime collaborationFrontend on Melp, a production realtime collaboration product (messaging, video, shared workspaces). Component architecture and state patterns that cut feature-dev time materially.ReactTypeScriptWebSockets
Every layer of a SaaS build, in one engagement.
“Full-stack” is the most overloaded word in this market. Some freelancers mean React plus a single API endpoint. Some mean wiring a CMS. I mean every layer of a production SaaS build, owned by one person from Figma frame to live URL — and this is what that actually includes.
Frontend
React + TypeScript, a documented component system, design tokens, WCAG AA accessibility, Lighthouse 95+ from day one.
API layer
REST or Server Actions with typed request/response validation (zod), error handling that returns useful messages, and rate limits where they matter.
Auth
Email + OAuth (Google, GitHub), session or JWT depending on the surface, role-based access control, refresh tokens, and proper logout. Multi-tenant when the product needs it.
Data
Schema design (Mongo or Postgres), indexes that match your queries, migrations, seed data for dev, and a backup story that exists before you need it.
File storage
Cloudflare R2 or S3 with signed URLs, virus scanning on user uploads when relevant, image processing through a CDN.
Background jobs
Queues (BullMQ, Inngest) for async work, cron for scheduled tasks, idempotent handlers so retries don't double-charge.
Billing
Stripe one-time and subscription, webhook handlers with signature verification, customer portal, dunning, and an admin override for the edge cases.
Admin
Role-gated routes, user impersonation for support, audit logs for sensitive actions, and CSV exports because someone always asks.
Observability
Structured logs, Sentry or equivalent for errors, uptime pings, a dashboard the founder can read without me.
Deploy
CI/CD on every push, preview branches per PR, one-click rollback, and environment variables documented in the repo. Vercel, Render, Railway, or a VPS — your call.
One engineer, one invoice, one accountable person from idea to live URL. If your build needs three of these layers and you don't want to coordinate three contractors, that's the brief I'm built for.
What founders ask before reaching out.
Do you only use MongoDB, or Postgres too?
Both. MongoDB for document-shaped data and rapid iteration on early-stage products. Postgres (usually via Supabase) when relational integrity, transactions, or vector search matter. Schema choice gets a written tradeoff brief, not a default.
Can you take over an existing MERN codebase?
Yes. The first week is usually an architecture audit — schema, API surface, auth, deployment, observability — followed by a written plan of what to extend versus rewrite. No big-bang rewrites unless the existing code is genuinely beyond rescue.
Express or Next.js route handlers?
Both work. Next.js route handlers when the frontend and backend live in one repo and benefit from shared types. Standalone Express or Fastify when the backend is genuinely separate, needs custom middleware, or runs on infra Next.js doesn't fit.
How do you handle auth?
Depends on the build. Supabase Auth or Clerk when the product needs email + OAuth fast. Custom JWT/session when there are unusual requirements (multi-tenant SSO, custom RBAC, embedded use cases). Always with refresh tokens, proper logout, and CSRF protection.
Can you do DevOps too?
Up to a point. CI/CD, Vercel/Render/Fly deployments, environment management, monitoring setup, and basic infra-as-code. For deep infra work — Kubernetes, custom VPCs, large-scale data — I partner with a specialist rather than fake expertise I don't have.
What's a typical MERN SaaS timeline?
A complete MVP — auth, billing, primary feature surface, admin panel, deployment — typically lands in 4 to 10 weeks. The scope doc in week one tells you exactly which features fit which timeline.
Let's see if it's a fit.
30-minute call. No pitch, no slides. Tell me what you're building, including the AI parts, and the constraints. I'll tell you if I can help, and who else to call if I can't.