Python Developer

Job Role: Senior Full Stack Developer — Backend Focus (Python / FastAPI / PostgreSQL)

Summary

We’re hiring a Senior Full Stack Developer with a strong backend focus building and operating production-grade Python services. The ideal candidate has deep core Python knowledge (not just scripting), hands-on experience with FastAPI, production PostgreSQL, modern testing and dependency tooling, and practical frontend experience with React/Next.js. This role requires proven experience working on live systems for Banking domain.

 

Key responsibilities (mapped to screening topics)

· Design, build, and maintain backend services using Python and FastAPI for high-availability production systems. (maps to Core Python, FastAPI, Production systems)

· Own API design and implementation, including OpenAPI specs, versioning, and backward compatibility. (maps to APIs)

· Implement and maintain data models, schema migrations, indexing strategies, and query tuning in PostgreSQL. (maps to PostgreSQL experience)

· Write comprehensive automated tests (unit, integration) and use pytest for test suites; maintain CI/CD test pipelines. (maps to pytest)

· Manage dependencies and reproducible builds using tools like poetry and pip-tools. (maps to poetry, pip-tools)

· Implement async patterns and concurrent processing where appropriate; understand GIL implications for concurrency decisions. (maps to asyncio, GIL)

· Instrument, monitor, and troubleshoot production incidents; lead post-incident reviews and remediation. (maps to production incident experience)

· Collaborate with frontend engineers to integrate React/Next.js UIs with Python backends; help define contracts and optimize client-server interactions. (maps to React/Next.js)

· Perform performance tuning, caching, and optimization of services and DB queries. (maps to optimization examples)

· Participate in architecture design, code reviews, and mentoring junior engineers. (maps to leadership/mentoring signals)

Required qualifications

· 5+ years professional software development experience, with at least 3 years working onsite (in-office or client-site) on development projects.

· 4+ years of core Python development experience (not just scripting).

· 2+ years hands-on experience building services with FastAPI (or equivalent modern ASGI frameworks).

· 3+ years of production PostgreSQL experience, including schema design, indexing, migrations, and query tuning.

· Strong familiarity with asyncio and concurrent patterns in Python; practical understanding of the GIL and implications for concurrency.

· Experienced with pytest for unit/integration testing and CI pipelines.

· Experience with dependency and packaging tools such as poetry and/or pip-tools; able to maintain reproducible environments.

· Experience running ASGI servers (uvicorn/hypercorn) in production.

· Frontend experience: 2+ years with React.js or Next.js and demonstrable examples of integrating JS frontends with Python backends (repo or demo links encouraged).

· Able to describe at least one production incident you helped resolve and one concrete performance optimization you implemented.

Preferred qualifications

· Experience with Docker, Kubernetes, and cloud deployments (AWS/GCP/Azure).

· Familiarity with observability tools (Prometheus, Grafana, Sentry, OpenTelemetry).

· Experience with CI/CD (GitHub Actions, GitLab CI, Jenkins).

· Experience maintaining mono-repos or multiple-service architectures.

· Familiarity with security best practices for APIs and data protection.

 

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