Senior Python Backend Developer (SWAT Team)

payabl.

2d•Remote

About The Position

We are building a new SWAT Engineering Team in Portugal to accelerate and assist our Core Gateway and Gateway Projects teams by developing a new internal platform and tooling layer. The Senior Backend Developer will play a key role in designing and building a new payment gateway support platform, focusing on performance, scalability, and developer efficiency. This is a high-impact engineering role combining hands-on backend development, architecture ownership, and technical leadership within the squad. You will work closely with Core Gateway, DevOps, and Platform teams to reduce complexity in legacy systems and improve system-wide efficiency.

Requirements

6+ years of backend engineering experience, with strong Python expertise.
Proven experience designing and delivering microservices architectures at scale.
Strong knowledge of FastAPI or Django (FastAPI preferred).
Experience building systems in high-performance, distributed environments.
Strong experience with API design (RESTful services, event-driven architecture is a plus).
Hands-on experience with Docker, CI/CD pipelines (GitLab preferred).
Cloud experience (AWS or GCP).
Strong understanding of system design, scalability, and reliability principles.
Strong ownership mindset with ability to drive technical direction independently.

Nice To Haves

Experience in fintech / payment systems / banking / high-volume transaction systems (strong plus).
Ability to work with or maintain legacy systems (Perl exposure is a plus, but not required).

Responsibilities

Design and build scalable Python-based microservices supporting a new internal gateway enablement platform.
Take ownership of system architecture decisions, ensuring long-term scalability, performance, and maintainability.
Develop tools and services that improve efficiency of existing Core Gateway and Gateway Projects teams.
Integrate and abstract third-party APIs and payment-related external services.
Define engineering standards for the SWAT team (coding practices, API design, service structure).
Collaborate closely with DevOps to design and improve CI/CD pipelines, deployment strategies, and observability.
Lead code reviews and ensure high engineering quality across the team.
Work across legacy (Perl) and modern systems, enabling gradual modernization.
Identify bottlenecks in existing systems and design technical solutions to remove them.
Act as a technical reference point within the SWAT team.