Senior Backend Engineer - Product API

About NyaayOS

NyaayOS is an AI-powered legal-tech platform built for the Indian legal ecosystem.

We help lawyers research, draft, manage matters, and practise law more efficiently using AI built specifically for Indian legal work.

We are an early-stage startup based in Mumbai, combining legal expertise with agentic AI systems, native function calling, ReAct workflows, and our own 7-Gate verification framework. We are not just adding an AI layer on top of existing tools — we are building the core infrastructure for how legal work will be done in India.

Joining NyaayOS means becoming part of an early team with high ownership, real product impact, and the opportunity to shape our technology, culture, and long-term direction from the ground up.

About The Role

• As a Senior Backend Engineer, you will architect and own the product API layer that makes our AI usable for lawyers every day.
• You will build the systems behind case files, draft versioning, billing, secure login, organisation-level access control, notifications, uploads, and exports.
• You will work with the frontend engineer and Product Manager to turn legal workflows into clean, scalable, and well-documented APIs for modules like Research, Draft Editor, and Matter Management.
• This role is ideal for someone who enjoys architecting backend systems, building product features, designing clean APIs, and solving multi-tenant SaaS problem.

*What You Will Own *

• Design and build clean REST and/or GraphQL APIs for matters, drafts, research sessions, saved searches, users, organisations, uploads, and exports.
• Own secure authentication and access control, including SSO, OTP, Google login, RBAC, audit logs, and organisation-level data isolation.
• Build billing and subscription workflows, including Razorpay integration, usage tracking, invoicing, failed payments, and plan changes.
• Create a flexible notification system for email, in-app alerts, and future channels like WhatsApp.
• Own document workflows such as S3 uploads, PDF exports, virus scanning, retention policies, and secure storage in the AWS Mumbai region.
• Design and maintain PostgreSQL data models for matters, drafts, users, organisations, billing records, and audit logs.
• Write clear API documentation and OpenAPI specs with request formats, responses, errors, and examples.
• Work closely with frontend and product teams to turn legal workflows into reliable, scalable, and easy-to-use APIs.

What We Are Looking For

• 5+ years of backend engineering experience with Python.
• Strong hands-on experience with FastAPI, Django REST Framework, or Flask.
• Solid PostgreSQL skills, including schema design, indexing, queries, transactions, and performance tuning.
• Experience building multi-tenant SaaS products with strong data isolation between organisations.
• Good understanding of authentication and authorization, including OAuth, OIDC, JWT, sessions, and RBAC.
• Strong REST and/or GraphQL API design skills, including versioning, pagination, rate limiting, and idempotency.
• Experience integrating payments or subscriptions using Razorpay, Stripe, or similar platforms.
• Experience handling billing workflows such as webhooks, retries, refunds, failed payments, and plan changes.
• Working knowledge of AWS services such as S3, SES, IAM, RDS, and secrets management.
• Ability to make practical engineering decisions around scalability, security, reliability, cloud cost, and product needs.
• Strong ownership mindset with the ability to push back on requirements that may create unnecessary technical debt.

Nice to Have

• Experience working in an early-stage or 0-to-1 startup environment.
• Experience building APIs from launch to early scale.
• Experience in legal-tech, regtech, e-discovery, fintech, healthtech, govtech, or other regulated domains.
• Understanding of Indian compliance, DPDPA, data residency, privacy, and security best practices.
• Experience with document-heavy products, exports, notifications, or workflow systems.
• Experience with background jobs or async processing using Celery, RQ, or similar tools.
• Exposure to TypeScript or Node.js.
• Ability to work closely with frontend engineers on API contracts.
• Open-source contributions, technical writing, or public speaking experience.