Senior Software Development Engineer in Test

LA International; Greater London; On-site; GBP 64,575 - 70,110; Full time

Job summary

LA International is seeking a hands-on Senior SDET to design, develop and maintain enterprise-grade automation across UI, API, database, MQ, Kafka and messaging layers in a hybrid London-based role.

You will contribute to framework modernization, build scalable automation, and ensure high-quality software through robust testing and diagnostics. Strong Java/JavaScript/Python and Selenium/Karate skills are required.

Qualifications

• Hands-on SDET with automation experience in enterprise systems.
• Strong scripting and programming skills across Java, JavaScript and Python.
• Proven ability to build and maintain automation frameworks and API/UI test suites.

Responsibilities

• Develop reusable automation libraries and framework components.
• Create robust API and UI automation using Selenium and Karate.
• Validate Kafka, MQ, and XML payloads; ensure ISO20022 compliance where needed.
• Build reusable test data solutions and centralized datasets.
• Improve framework reporting and structured logging for faster diagnosis.
• Integrate automation into CI/CD pipelines and automated deployments.
• Create technical documentation and maintain framework documentation.

Skills

Java

JavaScript

Python

Selenium

Karate

API Automation

CI/CD

SQL

Git

Tools

Selenium

Karate

Job description

SC - Security Cleared

Senior Software Development Engineer in Test

6 Month contract initially + Extensions

Based: Hybrid; 50% Onsite in London

Rate - £350 - £380 p/d via Umbrella

We have a great opportunity with a world leading organisation where you will be provided with all of the support and development to succeed. A progressive organisation where you can really make a difference. We have a great opportunity for a Senior Software Development Engineer in Test on a long term program of work.

We are looking for a hands‑on Senior SDET to develop, maintain, optimize, and execute enterprise‑grade automation solutions supporting critical banking payment systems. The successful candidate will contribute to framework modernization initiatives and develop scalable automation across UI, API, Database, MQ, Kafka, and Messaging layers.

Key Responsibilities:

Automation Development

• Develop reusable automation libraries
• Build automation framework components
• Create robust API automation suites
• Develop UI automation using Selenium POM
• Optimize automation execution performance

Messaging & Integration Testing

• Validate Kafka message flows
• Validate MQ integrations
• Verify XML payloads
• Implement XSD validation
• Validate ISO20022 messages

Test Data Management

• Build reusable test data solutions
• Maintain centralized test datasets
• Support integration and E2E testing

Reporting & Diagnostics

• Enhance framework reporting
• Implement structured logging
• Support root‑cause analysis
• Improve failure diagnostics

CI/CD

• Integrate automation suites into pipelines
• Support automated deployments
• Maintain continuous testing capabilities

Documentation

• Create technical documentation
• Maintain framework documentation
• Support knowledge‑sharing initiatives

Key Skills & Experience:

• Java
• JavaScript
• Python
• Selenium
• Karate
• API Automation
• CI/CD
• SQL
• Git

Due to the nature and urgency of this post, candidates holding or who have held high level security clearance in the past are most welcome to apply. Please note successful applicants will be required to be security cleared prior to appointment which can take a minimum 10 weeks. LA International is an award‑winning partner of choice for many of the world’s most influential companies and government organisations. Holding Enhanced Government Security Accreditation, we are recognised as the European market leader in the delivery of Security Cleared talent to organisations that demand the very highest levels of security, compliance and assurance.

An award‑winning organisation, having secured the prestigious Queens Award for Enterprise: International Trade over multiple years. We are committed to fostering an inclusive, equitable and accessible workplace where everyone feels valued and supported. We welcome applications from all individuals, regardless of background or identity, and we encourage candidates who may not meet every listed requirement to still apply. If you require any adjustments or support during the recruitment process, please let us know and we will work with you to ensure a fair and accessible experience.

Please Note: If a high volume of applications is received, only candidates shortlisted will be contacted.