Matěj Teplý

AI/ML engineer · backend developer · Zlín, CZ

Matěj Teplý

I build software that shows its work.

At work I build agentic RAG chatbots and AI agents in Python. Outside it I ship Android apps, most of them private and offline-first, plus browser extensions and web tools, usually with the tests, measurements and known limits written next to the code.

Selected work (08)

Each one told as problem, approach and result. The result is what I measured or shipped; where a measurement found a failure, it stays in.

  1. 01 CzechCore Offline Czech grammar correction AI and language
  2. 02 Project-Guard GitHub project audit AI and language
  3. 03 Project board Separates project phases from deployed versions Backend and web
  4. 04 RC Audio Lab An RC filter you can hear Backend and web
  5. 05 Band websites Exhalace and WeTheGods Backend and web
  6. 06 SeliaScan Scan, save, share Android apps
  7. 07 Selia Weather A forecast that names its sources Android apps
  8. 08 Intoniva Offline instrument tuner Android apps

All 34 projects, grouped →

How I work

  1. 01

    Measure, then claim.

    CzechCore publishes its precision, recall and rejected experiments. Selia Weather publishes its replay together with the failures.

  2. 02

    Private by default.

    The GitHub editions of SeliaScan, Intoniva, SeliaLists and Selia Cycles ask for no network access of their own, and your data stays on the device unless you choose to export, share or sync it.

  3. 03

    One job per tool.

    A per-tab equalizer, a SponsorBlock skipper, a tab-URL copier: small browser extensions that each do one thing.

Experience and education

  1. 2025 – now

    Fullstack AI Developer (Junior/Mid) · OKsystem

    AI-enabled applications across backend, frontend, APIs, databases, performance and architecture.

  2. 2026 – now

    AI Safety & Red Teaming Researcher · Freelance

    Independent safety evaluation and responsible vulnerability research on advanced generative AI systems.

  3. 2023 – 2025

    Student Azure Programming · Student Trainee Center

    Hands-on product, cloud and AI work, finished with Music Analyzer, which separates songs into stems.

  4. 2025 – 2030

    BSc Computer Software Engineering · Tomas Bata University in Zlín

  5. 2021 – 2025

    Mechanical Engineering · Střední průmyslová škola Zlín

AI systems
Agentic RAG, AI agents, context engineering, LLMs, chatbots, AI safety
Backend
Python, APIs, databases, automation, cloud
Product
TypeScript, JavaScript, Kotlin, HTML/CSS, C#, Git

Music

I play bass and sing backing vocals in WeTheGods, an alternative metalcore band from Uherské Hradiště, and I also play guitar, drums and saxophone. From 2025 to 2026 I played guitar in the rock band Exhalace. I built both bands’ websites and a tuner app, and I collect vinyl records.

Contact

For work, collaboration or a good technical problem.

majkeylab@gmail.com