Senior QA Engineer

Senior QA Engineer
We build and operate the financial backbone of the hair and beauty industry across 13 European countries. This role focuses on the critical intersection between Treatwell Connect, our SaaS platform used by tens of thousands of salon owners, and our Marketplace application used by millions of final customers. We are shaping a dedicated Payments QA automation function to ensure that every transaction, from a client booking on the app to a salon manager processing a checkout, is seamless and secure. We've seen firsthand that embedded, proactive QA is what separates reliable financial systems from reactive firefighting.

We're looking for a Senior QA engineer who is passionate about quality as a team discipline: someone who builds automation foundations, runs effective exploratory testing, and, above all, shifts how the people around them think about quality, not just how they personally test.
This role is primarily coaching and mentoring, your hands-on background is what earns you credibility with the teams.

You will be responsible for:
- Work with developers to build shared ownership of quality across engineering: encourage better unit testing, help them understand what good coverage looks like, and shift quality from a QA concern to a team habit.
- Evolve our automation framework, starting with API-level coverage of critical end-to-end happy path flows, the ones that must never break in a product shipping multiple times a day.
- Mentor QA team members into more technical and structured testing practice.
- Run exploratory testing to surface edge cases and failure modes that specs don't anticipate
- Own feature aftercare: monitor releases in production, track stability, and drive continuous improvement from what you find.
- Identify gaps that developers and PMs miss and bring them to the table early, contributing to product decisions throughout the cycle, not just at the end.
- Track QA metrics that matter, bug detection rate, release confidence, post-release defect counts, and own the narrative around what they mean for the product.

Our QA context

Our Payments context is uniquely complex, spanning our SaaS management tool, our consumer Marketplace and the accounting logic around every payment. A single transaction involves multiple touchpoints, and ensuring integrity across this entire ecosystem is paramount. The product moves fast, and any failure has a direct impact on the livelihoods of our beauty & wellness partners and the experience of their clients.

In this greenfield position within our Payments domain, you are empowered to reshape our testing evolution. Your mission is to establish a pragmatic, immediate framework that enhances delivery speed without causing friction, while architecting a robust, long-term testing strategy.

You will support 3 teams in the area on a stack that spans across multiple products.

About you:
- 7+ years of QA experience with hands-on automation work and structured manual and exploratory testing. You know when each approach is the right one.
- You've built automation frameworks before, not just used them. You're fluent in at least one programming language and can make and defend tooling decisions without a spec telling you what to choose.
- You take satisfaction from shifting how a team thinks about testing, not just from shipping test suites. Quality culture is something you actively build, not something you leave to others.
- You influence without authority: you bring developers, designers and product closer to quality, and the habits you build outlast your direct involvement.
- You can articulate risks clearly to engineers, PMs, and non-technical stakeholders, and you're comfortable pushing back when something isn't ready to ship.
- You want to make the people around you better, and you're patient enough to do it consistently.

Nice to haves:
- Experience as Technical/XP Coach
- Experience with observability and monitoring tools, particularly Datadog. Know