4Bell Technology

Job Description

Tech Stack

1. You will architect and govern the following stack:

• Frontend: Next.js + React

• Backend: Python + FastAPI

• API style: REST + OpenAPI

• Database: PostgreSQL + SQLAlchemy

• Async processing: Redis + Celery • Auth: OAuth 2.0 / OIDC (multi-tenant)

• AI/ML: Consumed via external API contracts

• Cloud: AWS

• Containerization: Docker + Kubernetes

Required Skills & Qualifications:

1. 10+ years of software engineering experience, with at least 4 years in a Solution Architect or Principal Engineer role.

2. Proven experience designing and delivering multi-tenant SaaS platforms from greenfield.

3. Deep expertise in Python and FastAPI — async programming, REST API design, dependency injection, and Pydantic data modelling.

4. Strong proficiency in React and modern frontend architecture — Next.js, SSR/SSG, state management, and component design systems. 5. Hands-on experience with PostgreSQL — schema design, query optimisation, multi-tenant data strategies, and SQLAlchemy ORM.

6. Solid understanding of OAuth 2.0, OIDC, JWT, and tenant-aware authentication and authorisation.

7. Experience defining and consuming API contracts (OpenAPI/Swagger) across teams or with third-party services.

8. Strong knowledge of cloud-native architecture on AWS — managed services, containerization, and autoscaling.

9. Experience with Docker and Kubernetes in production environments.

10. Ability to establish Python project structure, layering conventions, and coding standards that scale with team size.

11. Experience working on AI tools like Claude for code development and debugging.