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- Tasks: Architect and deliver world-class test automation frameworks for data validation and migration.
- Company: Leading financial services organisation with a focus on innovation and technical excellence.
- Benefits: Competitive salary up to £98k, hybrid working model, and collaborative culture.
- Why this job: Make a significant impact in a dynamic environment while driving automation strategies.
- Qualifications: Advanced data testing expertise, SQL, Databricks/Snowflake experience, and 4+ years in automation.
- Other info: Join a forward-thinking team in central London with excellent career growth opportunities.
The predicted salary is between 78000 - 117000 £ per year.
Principal SDET – Data Framework Architect | Hybrid (London) | Up to £98k | Sorry, no sponsorship
Eligibility: Due to background screening requirements, candidates must hold British Citizenship or Indefinite Leave to Remain (ILR) to be considered.
Please only apply if you have advanced data testing expertise, including data migrations, SQL, and experience with Databricks and/or Snowflake. A minimum of 4 years’ hands‑on experience is required coupled with architect framework building skills! (All non‑negotiable).
Overview
Optimal have partnered with a leading financial services organisation is seeking a Principal Software Development Engineer in Test (SDET) to architect and deliver world-class test automation frameworks. This is a strategic and hands-on opportunity for a technical expert in data migration testing, ETL validation, and automation framework design using C# and Python.
You’ll drive the technical direction for automation, working across data, backend, and UI layers – embedding quality at scale across complex, high-trust systems.
Core Focus Areas
Data Validation & Migration Testing
- Advanced data validation using SQL, Snowflake, and Databricks
- Hands-on testing of data pipelines, ETL processes, and large-scale migrations
- Strong understanding of data lineage, reconciliation, and transformation accuracy
Automation Framework Development
- Framework architecture from scratch in enterprise-grade ecosystems
- SpecFlow, Playwright, Cypress, and Selenium (incl. Recnroll) – UI, API, and end-to-end automation
- Full lifecycle automation ownership – design, implementation, and CI/CD integration
Performance & Reliability Testing
- Tools: JMeter, k6, Gatling – load, stress, and performance benchmarking across APIs and distributed systems
- Establish and maintain performance baselines and regression monitoring
Infrastructure & DevOps Integration
- Cloud: AWS, Azure DevOps, GCP – testing in containerised, scalable environments
- CI/CD: Seamless integration of automation suites and quality gates into distributed pipelines
Strategic & Architectural Impact
- Design and scale robust automation frameworks from scratch
- Embed quality engineering principles across microservices, APIs, and event-driven systems
- Contribute to architectural decisions influencing reliability, maintainability, and performance
- Operate as a technical authority and hands-on engineer, not a passive test lead
Ideal Background
- Strong background in data-centric testing and enterprise-scale system validation
- Experience within asset management, investment platforms, or financial services environments
- Proven ability to lead automation strategy while remaining 80%+ hands-on
- Excellent communicator and collaborator, working closely with developers and DevOps teams
Working Model
- Hybrid: 2–3 days per week in central London
- Collaborative, forward-thinking engineering culture focused on technical excellence and innovation
If interest and tick all of the above boxes reach out to us at Optimal for a quick response.
Principal SDET | Data employer: Optimal
Contact Detail:
Optimal Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Principal SDET | Data
✨Tip Number 1
Network like a pro! Reach out to your connections in the industry, especially those who work in financial services or data testing. A friendly chat can lead to insider info about job openings that might not even be advertised yet.
✨Tip Number 2
Show off your skills! Create a portfolio showcasing your previous projects, especially those involving data migrations and automation frameworks. This will give potential employers a clear view of what you can bring to the table.
✨Tip Number 3
Prepare for interviews by brushing up on your technical knowledge. Be ready to discuss your experience with SQL, Databricks, and Snowflake, as well as your approach to building automation frameworks from scratch.
✨Tip Number 4
Don’t forget to apply through our website! It’s the best way to ensure your application gets seen by the right people. Plus, we love hearing from candidates who are passionate about quality engineering and innovation.
We think you need these skills to ace Principal SDET | Data
Some tips for your application 🫡
Tailor Your CV: Make sure your CV highlights your advanced data testing expertise and hands-on experience. We want to see your skills in SQL, Databricks, and Snowflake shine through, so don’t hold back!
Craft a Compelling Cover Letter: Your cover letter is your chance to tell us why you’re the perfect fit for the Principal SDET role. Share specific examples of your experience with automation frameworks and data migration testing to grab our attention.
Showcase Your Technical Skills: We’re looking for someone who can architect frameworks from scratch. Be sure to mention your experience with tools like SpecFlow, Playwright, and CI/CD integration. Let us know how you’ve embedded quality at scale in past projects!
Apply Through Our Website: To make sure your application gets the attention it deserves, apply directly through our website. It’s the best way for us to keep track of your application and get back to you quickly!
How to prepare for a job interview at Optimal
✨Know Your Data Inside Out
Make sure you brush up on your advanced data testing expertise, especially around SQL, Databricks, and Snowflake. Be ready to discuss specific projects where you've handled data migrations or ETL validation, as this will show your hands-on experience.
✨Showcase Your Framework Skills
Prepare to talk about your experience in architecting automation frameworks. Highlight any frameworks you've built from scratch using C# or Python, and be ready to explain your design choices and how they impacted the overall quality of the systems.
✨Demonstrate Your Technical Authority
As a Principal SDET, you'll need to operate as a technical authority. Be prepared to discuss architectural decisions you've made in previous roles and how they influenced system reliability and performance. This is your chance to shine as a hands-on engineer!
✨Communicate Effectively
Since collaboration is key, practice articulating your thoughts clearly. Be ready to discuss how you've worked with developers and DevOps teams in the past. Good communication can set you apart, so don’t underestimate its importance!