Senior Software Development Engineer in Test

Luxoft Poland; Polska; On-site; PLN 180,000 - 240,000; Full time

Job summary

Luxoft Poland is seeking a hands-on SDET to own UI test automation for our in-house trading platform. You will extend the Playwright framework, enable streaming multi-window workflows, and add quality gates to CI for front-end performance.

You will co-architect a unified testing framework with our backend SDET, covering UI, API, messaging, data and performance tests in one place, and drive reliability across release cycles.

Qualifications

• 5+ years of UI test automation, including designing or significantly extending a framework.
• Working Python skills (pytest, Playwright for Python): test tooling, data setup, backend checks inside UI scenarios, and contributing to the shared framework.
• Experience testing React apps with complex data grids (AG Grid or similar), dynamic forms and heavy client-side state.
• Front-end performance testing experience: Profiling with Chrome DevTools Performance and Memory panels, Lighthouse and performance APIs.
• Diagnosis: finding long tasks, layout thrashing and memory leaks.
• Budgets: setting performance budgets and enforcing them in CI.
• CI/CD experience with Azure DevOps (preferred) or Jenkins/GitHub Actions, and Git.
• Experience building isolated test environments: Linux shell scripting, Docker, AWS (EC2, ECS/EKS, S3, IAM, VPC, CloudWatch).
• Infrastructure as code: Terraform, CloudFormation or CDK.
• Strong reliability habits: isolated tests, deterministic waits, retries, triage of flaky tests.
• Experience with test reporting and traceability (Playwright reports, Allure, Azure Test Plans, TestRail).
• Clear communication and good documentation.
• Nice to have: Trading or buy-side experience; Desktop container automation; Component testing; Accessibility and visual-regression testing; OpenTelemetry or RUM tools.

Responsibilities

• Co-architect and co-own a unified testing framework that covers every area we test.
• Shared foundations: fixtures, test data, configuration, environments and reporting across UI, API, Kafka, database and performance suites.
• Cross-layer scenarios: a test may cross UI, events and database checks.
• One quality view: single view of release quality from all suites.
• Design, build and maintain end-to-end and component tests with Playwright and TypeScript for trading and analytics workflows.
• Extend our shared test toolkit: page objects, fixtures, and mocks of desktop-container APIs.
• Build front-end harnesses for real-time data with mocked WebSocket and REST responses.
• Cover UI failure modes: disconnects, expired sessions, permission failures, bursty feeds, stale data.
• Own front-end performance testing: startup time, time-to-first-data, and high update-rate resilience.
• Grid performance: render/scroll testing for large data grids.
• Container resources: monitor memory growth and CPU use in long-running sessions.
• Regression gates: convert results into CI-breaking budgets.
• Build isolated on-demand test environments on Linux and AWS; lifecycle per branch/run.

Skills

UI test automation

Python

Playwright (Python)

React testing

CI/CD

Tools

Docker

Docker Compose

AWS

Terraform

Azure DevOps

Git

GitHub Actions

Job description

We build an in-house trading platform covering order management, execution, and data analysis. The front end is a set of TypeScript/React apps running in a desktop container and streaming real-time data.

We're hiring a hands-on SDET to own UI test automation: extend our Playwright framework, make streaming, multi-window workflows testable, and add quality gates to CI, including front-end performance. You'll co-architect and co-own a unified testing framework with our backend SDET. It covers UI, API, messaging, data and performance tests in one place.

Responsibilities

Co-architect and co-own, with our backend SDET, a unified testing framework that covers every area we test:

Shared foundations: fixtures, test data, configuration, environments and reporting are shared across UI, API, Kafka, database and performance suites.

Cross-layer scenarios: one scenario can cross layers. For example, a test places an order in the UI, then checks the resulting event and the database record.

One quality view: results from every suite feed a single view of release quality.

Design, build and maintain end-to-end and component tests with Playwright and TypeScript for trading and analytics workflows.

Extend our shared test toolkit: page objects, fixtures, and mocks of desktop-container APIs.

Build front-end harnesses for real-time data: mocked WebSocket and REST responses, controlled test data, and deterministic replay of streaming updates.

Cover UI failure modes: disconnects and reconnects, expired sessions, permission failures, bursty feeds, and stale data.

Own front-end performance testing:

Startup and responsiveness: measure app startup and time-to-first-data, and check that the UI stays responsive under high update rates.

Grid behaviour at scale: measure render and scroll performance of grids with tens of thousands of rows.

Container resources: track memory growth and leaks in long-running desktop sessions, and CPU cost per window.

Regression gates: turn the results into budgets that fail CI on a regression.

Build and maintain isolated, on-demand test environments on Linux and AWS:

Lifecycle: environments are created per branch or per run, start with seeded data and known state, and are torn down automatically

Isolation: test runs don't interfere with each other or with shared environments.

Validate front-end/back-end contracts and payload schemas.

Run UI suites in CI/CD: sharded parallel runs, scheduled regressions, and reporting on pull requests.

Make failures diagnosable: Playwright traces, screenshots and video, and correlation with telemetry.

Work with UI engineers, business analysts and traders to automate critical workflows and define QA acceptance criteria.

Use AI-assisted tools where they help with writing, maintaining and triaging tests.

Must have

5+ years of UI test automation, including designing or significantly extending a framework.

Working Python skills (pytest, Playwright for Python): test tooling, data setup, backend checks inside UI scenarios, and contributing to the shared framework.

Experience testing React apps with complex data grids (AG Grid or similar), dynamic forms and heavy client-side state.

Front-end performance testing experience:

Profiling: Chrome DevTools Performance and Memory panels, and the Lighthouse and performance APIs.

Diagnosis: finding long tasks, layout thrashing and memory leaks.

Budgets: setting performance budgets and enforcing them in CI.

CI/CD experience with Azure DevOps (preferred) or Jenkins/GitHub Actions, and Git.

Experience building isolated test environments:

Linux: comfortable on the command line, with shell scripting, processes, networking and log troubleshooting.

Docker: Docker and Docker Compose.

AWS: EC2, ECS or EKS, S3, IAM, VPC and CloudWatch.

Infrastructure as code: Terraform, CloudFormation or CDK.

Strong reliability habits: isolated tests, deterministic waits instead of sleeps, controlled retries, and triage of flaky tests.

Experience with test reporting and traceability (Playwright reports, Allure, Azure Test Plans, TestRail).

Clear communication and good documentation.

Nice to have

Trading or buy-side experience: OMS/EMS, algos, positions, allocations, or risk.

Java exposure, enough to read service code and contribute to backend suites in the shared framework.

Desktop container automation: Electron, OpenFin, or similar.

Component testing (Vitest or Jest). Storybook visual or interaction testing.

Accessibility and visual-regression testing.

React Profiler and familiarity with React rendering performance (memoization, virtualization).

OpenTelemetry or similar real-user-monitoring tools, and using production RUM data to pick performance test scenarios.