Senior Backend Developer (FASTAPI + AWS)

Job Title: Backend Engineer (FastAPI + AWS)

Location: Pune (Onsite)

Work Experience: 4+ years

Job Description

Role Overview

We are looking for a highly skilled Backend Engineer with strong experience in FastAPI, AWS infrastructure, authentication systems, payment integrations, monitoring systems, sockets, and scalable backend architecture. The candidate should be comfortable building production-grade APIs, working with real-time systems, and handling cloud-native deployments. This role involves working on scalable AI-driven web and mobile platforms with integrations across payments, subscriptions, authentication, analytics, monitoring, and real-time communication systems.

Required Skills

Backend Development - At least 4 years of experience is Mandatory

Strong experience with Python and FastAPI

Experience designing scalable REST APIs and async backend systems

Deep understanding of backend architecture, middleware, dependency injection, and background task handling

Strong experience with WebSockets, socket lifecycle management, reconnection handling, and real-time communication systems

Experience handling concurrent socket connections and event-driven systems

Knowledge of microservice-oriented architecture is a plus

AWS & Cloud Infrastructure

Strong hands-on experience with:

EC2

S3

DynamoDB

Load Balancers

Experience with production deployments, scaling, monitoring, and security hardening

Understanding of CI/CD pipelines and deployment automation

Database Experience

Strong experience with DynamoDB

Must understand:

GSIs (Global Secondary Indexes)

Query optimization

Partition key design

Scaling considerations

Single-table design concepts

Experience with MongoDB/PostgreSQL is a plus

Authentication & Security

Experience with Auth0 or similar authentication providers

Understanding of:

JWT authentication

Session handling

OAuth flows

RBAC / permission systems

Secure API design

Experience implementing secure backend authorization flows

Payments & Subscription Systems

Experience integrating Stripe APIs

Knowledge of:

Subscription lifecycle management

Webhooks

Payment intents

Billing flows

Invoice handling

Experience with RevenueCat integration for mobile subscription management is highly preferred

Monitoring & Reliability

Experience with monitoring and observability tools such as:

CloudWatch

Datadog

Grafana

Prometheus

Sentry

Ability to monitor logs, infrastructure health, API performance, socket reliability, and production incidents

Experience with alerting systems and production debugging workflows

Additional Preferred Skills

Experience supporting Flutter or React-based applications

Familiarity with mobile backend requirements

Experience debugging production systems and improving reliability/performance

Responsibilities

Develop and maintain scalable backend APIs using FastAPI

Design secure and efficient backend architecture

Manage AWS infrastructure and deployment pipelines

Build real-time communication systems using WebSockets/sockets

Build payment and subscription systems using Stripe and RevenueCat

Optimize DynamoDB schemas and GSI usage for performance

Implement authentication and authorization systems

Monitor infrastructure, backend services, socket systems, and production environments

Improve system reliability, performance, and scalability

Collaborate with frontend, mobile, and DevOps teams

Participate in debugging, testing, and production monitoring

Ideal Candidate Should have:

Strong problem-solving ability

Comfortable working in fast-paced startup environments

Able to independently design and implement backend systems

Good understanding of scalability and production engineering

Strong ownership mindset and debugging skills