Senior Python Backend Architect — FinTech/Banking

Ascendion; Bromley; On-site; GBP 90,000 - 130,000; Full time

Job summary

Ascendion is seeking an experienced Senior Python Developer to join a leading global banking client in the United Kingdom. You will design, develop, and maintain scalable Python backend services and batch processing solutions while optimizing SQL queries across multiple databases.

The role requires Linux proficiency, automation, and strong testing with PyTest/TDD/BDD. Ideal candidates have 12+ years of Python development experience, solid OO design skills, and familiarity with enterprise

Qualifications

• 12+ years of Python development experience.
• Strong Python OOP and software design expertise.
• SQL across PostgreSQL, MySQL, or SQL Server.
• Linux/Unix and Bash scripting.
• Experience with Autosys (or similar enterprise scheduling tools).
• Git, JIRA, Agile/Scrum.
• PyTest, TDD, and BDD (Behave).
• Experience in Banking or Financial Services is highly preferred.

Responsibilities

• Design, develop, and maintain scalable Python applications using OOP and software design principles.
• Build and optimize backend services and batch processing applications.
• Write and optimize complex SQL queries across PostgreSQL, MySQL, or SQL Server.
• Work in Linux environments, including bash scripting and deployments.
• Develop and maintain automated testing frameworks using PyTest, TDD, and BDD (Behave).
• Manage source code using Git and participate in code reviews and CI/CD workflows.
• Work with Agile teams using JIRA and support enterprise application delivery.

Skills

Python development

Python OOP

SQL

Linux scripting

Autosys

Git/JIRA/Agile

PyTest/BDD

Banking domain

Tools

Git

JIRA

Autosys

Job description

Ascendion is seeking an experienced Senior Python Developer to join a leading global banking client in the United Kingdom. You will design, develop, and maintain scalable Python backend services and batch processing solutions while optimizing SQL queries across multiple databases.

The role requires Linux proficiency, automation, and strong testing with PyTest/TDD/BDD. Ideal candidates have 12+ years of Python development experience, solid OO design skills, and familiarity with enterprise