Senior QA Engineer

At Adapty, we make it easy for mobile apps to manage in-app purchases and paywalls. We power 20K+ apps, process $3B+ in subscriptions every year, and have been growing fast for the last four years. Our mission is simple: make apps rich.

We are a team of 210+ passionate, product-driven people who love solving big challenges. Backed by top investors like 500 Startups and Surface Ventures, we are building one of mobile's fastest-growing SaaS companies and aiming for number one worldwide.

Why this role matters

Flow Builder is one of Adapty's core products and the biggest bet we're making right now. Our customers use it to build the screens their users see around the purchase: onboarding, quizzes, paywalls and post-purchase screens. They assemble multi-screen flows with branching, variables and conditional content right in the browser. The Adapty SDK renders those flows natively on iOS, Android, React Native, Flutter and Capacitor, so a change published in the editor reaches users without an app release.

We're building the most capable native builder on the market, and that sets the bar for engineering. It's an editor with the complexity of a design tool: a document model, a layer tree, layout and styling systems, a preview that has to agree with five native runtimes, and an AI Editor that rewrites the screen from a prompt. Closer to Figma than to a dashboard – and subscription revenue runs through every screen it renders.

We're looking for a senior QA engineer to own quality in a product team: testing throughout development, a regression suite that keeps growing, and exploratory testing. Small, strong team. The product is public, so you can see what you'd be testing before you talk to us: adapty.io/docs/adapty-flow-builder

What you'll do

• Write and maintain test cases and acceptance criteria tied to business requirements.

• Clarify requirements, architecture and product decisions with the team.

• Run end-to-end, regression and integration testing across backend, frontend, SDK and native mobile.

• Assess release risks and bug severity, and report clearly and fast.

• Keep the test case library reusable and coverage growing.

• Support and improve the testing framework and infrastructure.

About you

• You keep quality steady in a client-server web app when requirements shift and priorities compete.

• You can explain why a test suite covers a feature well enough.

• You know what to ask when a feature enters development.

• You build an end-to-end quality model across backend, frontend, SDK and native mobile — and test parts in isolation when one side isn't ready.

• You're fluent in testing process, quality metrics and Agile trade-offs.

• You test APIs with Postman and automate with Python, Playwright and pytest, or an equivalent stack.

• You work with VCS, Docker, Linux and CI/CD — or know how to work with the people who own them.

Nice to have

• You've worked on a design tool, page builder or workflow editor.

• You've tested editor-class interfaces, SDKs or native mobile UI across platforms.

• You steer coding agents and check their output.

• Strong product with industry-best metrics. Adapty is among the top 5% fastest-growing SaaS companies.

• Exceptional compensation directly tied to your results.

• Direct communication and ownership. No bureaucracy, no politics, just impact.

• Flexible remote work. Join us from anywhere or work onsite in our Belgrade or London offices.

• Professional support. Language learning, sports, health insurance, laptop coverage, and more.