Senior Full Stack Developer
First seen by Alion on Aug 21, 2026.
Operating from Gurugram.
Role Overview :
As a Senior Full Stack Developer you will own features across the entire stack, a change to bookings or payments typically touches the NestJS API, the consumer web app, the expert dashboard and both React Native apps, and you will carry it through all of them rather than handing it off.
Shipping product, and giving a fast-built system the foundations it has outgrown, versioned database migrations, CI, meaningful test coverage, observability and documentation. Real money and regulated personal data move through this platform daily, so correctness in the payment and KYC paths is the part of the job that is not negotiable.
Key Responsibilities :
- Build and ship features end to end across a NestJS API, two Next.js 16 applications and two Expo / React Native applications.
- Own the money paths: Razorpay and Cashfree behind a single gateway abstraction, wallet ledger, subscriptions, coupons, invoicing and expert payouts, with idempotent webhooks, reconciliation and a complete audit trail.
- Design and evolve the PostgreSQL schema, own indexing and query performance, and lead the migration from auto-synchronised schema to versioned, reviewed migrations without downtime or data loss.
- Establish the engineering safety net: CI on every pull request, tests around bookings, payments and KYC, error tracking and alerting.
- Build out expert onboarding, the KYC document review workflow and the S3-backed document vault, including access control and retention.
Required Skillset :
- 4+ years building production web software, including at least 2 years of TypeScript across both server and client.
- Strong Node.js server experience. NestJS is ideal; solid Express or Fastify with real modular-architecture and dependency-injection experience is equally acceptable.
- Genuine PostgreSQL depth - schema design, indexing, query tuning, and migrations you have personally run against a live production database.
- Production React, including at least one modern Next.js App Router application.
- Hands-on integration of a payment gateway end to end: checkout, webhooks, refunds and reconciliation. Indian gateways (Razorpay, Cashfree, PayU, PhonePe, Paytm) strongly preferred.
- Experience owning a system that handles real money or regulated personal data, with a specific account of something that went wrong in production and how you resolved it.
- Full-time, in-office in Gurugram.
- React Native or Expo applications shipped to the App Store or Play Store.
- Real-time audio/video experience - Agora, Twilio, LiveKit, 100ms or Daily.
- LLM features in production: RAG, embeddings, vector search, streaming, evaluation, cost control.
- KYC, identity verification, or Indian fintech and compliance experience.
- Having taken a codebase from no CI and no tests to a working pipeline.
- Marketplace or two-sided platform experience, supply onboarding, payouts, take-rate, ratings.
- AWS depth: S3, ECS or EC2, RDS, CloudWatch, Bedrock.
Who This Role Is Not For :
- Anyone expecting a clean codebase and a defined ticket queue. Neither exists yet.
- Anyone wanting to specialise narrowly, this role spans server, web, mobile and infrastructure in the same week.
- Anyone unwilling to do operational work. Migrations, CI and on-call are a substantial part of the first quarter.
Skills
TypeScript, Next.js, NestJS, PostgreSQL, React Native, AWS, Full Stack