Treneris
Professional client-management tools for the world of sport and fitness, in a simple, accessible, and affordable form.
Visit treneris.sk
Michaela Carpenter
Co-founder of Treneris
Michaela Carpenter is a co-founder of Treneris. The idea to build a solution for coaches came to her naturally: as a former figure skater and the sister of a fitness trainer, she knows the sports world and the everyday challenges of coaches first-hand.
Over more than 12 years she has worked in international companies in Slovakia and abroad, including East Africa and the United States. She specialises in setting up client-management and customer-care processes and in using technology to raise customer satisfaction and grow businesses. She has led and delivered projects for thousands of customers and now writes about that experience for podnikajte.sk and the weekly magazine Trend.
Snapshot
- Category
- SaaS · Coaching operations
- Stack
- Expo and React Native mobile app in a monorepo, with a web surface alongside it
- Status
- Live, in production
- Our role
- Product build, end to end, with the domain owner on the product side
Professional tools for coaches, not just for corporations
During that work she realised one fundamental thing. Quality client-management tools exist, but they are built mainly for large corporations. Smaller entrepreneurs, coaches, and sports clubs often run on a patchwork of separate apps, spreadsheets, and manual admin that robs them of time and money.
Treneris was born from that insight. It brings professional client-management tools to the world of sport and fitness in a simple, accessible, and affordable form. The goal is not to build yet another booking system, but to give coaches the space to focus on what matters most, their clients, while payments, communication, and organisation are handled by technology.
Michaela believes even small businesses deserve tools that were until now the privilege of large companies. Treneris combines international business experience with the real needs of the sports community to help coaches build a more professional, profitable, and sustainable business.
What we built
One system a coaching practice runs from: the client roster, training schedules, payment tracking, and AI-assisted meal planning, in a mobile app the coach uses between sessions rather than at a desk.
The design constraint was that a coach must never have to leave it to finish a task. Anything that would have sent someone back to a spreadsheet became a feature.
How fast, and how
The build ran on the internal platform rather than on headcount. A research pass mapped the existing surfaces before anything was written, specialist agents wrote one surface each in parallel, and every change went through verifiers that report only pass or fail: type-check, lint, build, and a clean boot for anything on the server side.
Because the app is mobile, the tester tier is a simulator rather than a browser: agents drive the running build on an iOS Simulator and an Android emulator, capture what they see, and report a pass, a failure, or a blocked run with the reason.
The human gates were the same ones described on the method page. No agent merged anything. Schema changes were reviewed before they were generated. Anything that touched production stopped and waited.
The stack
- Expo and React Native for the mobile application, in a monorepo under apps/mobile
- A web surface alongside the app for the work that does not belong on a phone
- Simulator-driven verification on both iOS and Android as part of the delivery loop
Where it is now
Treneris is live at treneris.sk and in use by coaches running their practice on it.