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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