Senior Test Automation Engineer / SDET (Remote)

As a Senior Test Automation Engineer, you will build the test infrastructure of a crypto payment platform: custody, AML and transaction screening, stablecoin settlement. This is a horizontal engineering role serving all development squads, covering both our current platform and the new platform we are building. Your product is the infrastructure that makes testing cheap for every engineer: vendor mocks, fast CI feedback, reliable test suites, and easy-to-use test tooling. Success is measured by how cheaply and confidently the engineering team ships.

• Design and build stateful mocks and simulators of third-party vendor APIs (custody, KYC/KYB, screening providers), serving both the current and the new platform
• Implement contract tests that run on schedule against real vendor sandboxes and catch unannounced API changes before they reach production
• Build test data and environment tooling: one-command environments with meaningful state
• Own the CI test pipeline: fast feedback on every pull request, heavier integration suites nightly and pre-release, parallelization
• Eliminate flaky tests: quarantine, statistics, root-cause analysis, so the team trusts a red build
• Create test-writing scaffolding (helper libraries, fixtures, object builders) and well-documented test patterns that also serve as templates for AI-assisted test generation
• Coach engineers on writing effective tests through reviews and pairing, so that each team owns the quality of its own code
• Build production-adjacent checks: post-deploy smoke tests, synthetic transactions, automated verification before traffic is switched to a service

• 5+ years as a software engineer with substantial test-infrastructure ownership (SDET, platform engineering, or backend engineering with heavy testing responsibility)
• Strong TypeScript: our backend services and test automation are TypeScript
• Experience building test frameworks and harnesses from scratch, not only writing tests on top of existing ones
• Hands-on experience with a modern automation framework, i.e. Playwright
• Experience designing test stages in CI/CD pipelines (e.g. GitLab CI), including parallelization and selective test execution
• API testing and mocking/stubbing of third-party services
• Proficient daily use of AI coding tools, with the ability to review AI-generated code quickly and critically
• Prior crypto experience is optional; building a working understanding of crypto and stablecoin payment flows (custody, settlement, screening) on the job is a mandatory part of the role
• High agency: this is a horizontal role without daily supervision; you find testing friction yourself, decide what to build, and defend its priority
• Strong written and verbal communication in English

• Fintech, payments, or crypto domain; understanding of testing money flows: idempotency, reconciliation, state machines
• Contract testing tooling (e.g. Pact or similar)
• Performance and load testing
• Experience working in a regulated environment (financial services, healthcare)
• Test management tooling such as TestRail

Reports to: Engineering Manager. You will align testing strategy with our QA Lead.

• Build the test infrastructure of a crypto payment platform from scratch, with a greenfield platform as your first adopter
• Your framework multiplies the output of every engineer in the organization
• AI-first engineering culture: your test patterns directly power AI-assisted development

Remote. EU, USA, Argentina, Brazil. A minimum of 4 hours of daily overlap with Central European working hours is required.

As an independent contractor, you'll enjoy the flexibility to determine how and when you deliver your work, while partnering closely with our team to meet agreed milestones and business objectives. Compensation and engagement terms will be outlined in your contractor agreement.

Additional Benefits

• Company issued laptop
• Technology Accessories
• Annual In-Person Full-Team Meetup