Backend Developer

Job Summary

We are seeking a Backend Developer proficient in Python and FastAPI to design, build, and scale the server-side infrastructure powering our fitness-tech platform. You will architect robust APIs, manage asynchronous task pipelines, orchestrate AI service integrations, and ensure the platform can handle rapid user growth, while maintaining security, reliability, and clean code standards.

Responsibilities

• Design and develop high-performance RESTful APIs using FastAPI with async/await patterns, dependency injection, and automatic OpenAPI documentation.
• Architect and manage relational database schemas in MySQL, including optimized queries, migrations (Alembic), and indexing strategies.
• Implement Redis for caching, session management, rate limiting, real-time leaderboards, and pub/sub messaging.
• Build and manage distributed task queues and scheduled jobs using Celery with Redis or RabbitMQ.
• Design and integrate AI/ML service layers for OpenAI, Gemini, Claude, and other LLM APIs.
• Architect payment processing flows with Razorpay and Stripe, including subscriptions, webhooks, and PCI-DSS compliance.
• Implement authentication and authorization using JWT, OAuth 2.0, and Role-Based Access Control (RBAC).
• Write comprehensive unit tests with pytest and maintain over 80% code coverage.
• Design scalable microservice communication patterns, event-driven architectures, and message queues.
• Create and maintain API documentation, technical documentation, and architecture decision records (ADRs).
• Collaborate with frontend and DevOps teams for deployment, monitoring, and scaling.

Requirements & Qualifications

• 2-3 years of professional backend development experience with Python.
• Strong proficiency in FastAPI (or similar async frameworks like Starlette).
• Solid experience with MySQL including schema design, query optimization, stored procedures, and migrations.
• Hands-on experience with Redis for caching, queues, and real-time data structures.
• Production experience with Celery for task scheduling, retries, and monitoring using Flower.
• Understanding of AI/ML integration patterns including prompt engineering, token management, and streaming.
• Experience integrating payment gateways with webhook handling, idempotency, and reconciliation.
• Strong understanding of RESTful API design, versioning, authentication, and error handling.
• Proficiency with Git, Docker, and Linux-based development environments.
• Familiarity with AWS services including EC2, RDS, S3, SQS, and Lambda.
• Knowledge of security best practices including OWASP Top 10, input validation, and secrets management.

Tools & Technologies

• Python
• FastAPI
• MySQL
• Redis
• Celery
• RabbitMQ
• Alembic
• SQLAlchemy
• Pydantic
• Docker
• AWS (EC2, RDS, S3, SQS)
• Git
• GitHub Actions
• Postman
• Swagger/OpenAPI
• pytest
• Flower
• Sentry
• Grafana

Nice to Have

• Experience with event-driven architecture (Kafka, AWS SNS/SQS).
• Familiarity with GraphQL or gRPC.
• Exposure to Infrastructure as Code (Terraform, CloudFormation).
• Experience with WebSocket and real-time communication.
• Knowledge of data pipeline orchestration using Airflow or Prefect.

Disclaimer: This job posting has been aggregated from external source. Role details, content, and availability are subject to change. Applicants are advised to confirm the latest information directly on the company website before applying.