Experience
- Allegro, Warsaw12.2021 — present
Head of Data Annotation & QA Services
- Built the quality-assurance framework that gates AI products before release — definitions of done, acceptance criteria, and monitoring standards.
- Scaled the organisation’s data-annotation capability — onboarded external vendor partners, rebuilt the annotation toolchain, and led the team that trained 700+ people across product and technology in Data-Centric AI over four years.
- Deliver the datasets used to train and evaluate AI solutions across translation, search, the product catalogue, and many other areas — serving both end customers and teams inside the organisation.
- Delivered 200+ annotation projects for AI teams across the organisation.
- Samsung, Warsaw04.2017 — 11.2021
Head of Language Data Operations
- Led an end-to-end ML dataset operation for NLP systems — a Polish annotation team plus operational teams in Germany, France, Spain, and Italy (50+ engineers and domain experts across 5 countries).
- Built and ran the data infrastructure and annotation toolchains the multinational R&D teams depended on for NLP dataset delivery.
- Samsung, Warsaw03.2011 — 03.2017
Data Engineer and Technical Leader
- Led speech data collection and transcription pipelines for Automatic Speech Recognition across 8 languages and Samsung voice-enabled devices, feeding the voice assistants shipped in European markets.
Education
- Adam Mickiewicz University, Poznań09.2019 — 06.2024
Ph.D. in Computer Science
Application of speech datasets management methods for the evaluation of Automatic Speech Recognition systems for Polish.
- Poznań University of Technology10.2005 — 06.2010
M.Sc. in Telecommunications
Specialization: multimedia systems and signal processing.
Publications
Profiles: Google Scholar · ResearchGate · dblp
- Junczyk, M., Christop, I., & Pęzik, P. (2024). Task 3: Polish Automatic Speech Recognition Challenge. PolEval 2024 Workshop. [pdf]
- Junczyk, M. (2024). BIGOS V2 — Benchmark for Polish ASR: Curated Datasets and Tools for Reproducible Evaluation. NeurIPS 2024 (Datasets & Benchmarks Track). [poster]
- Junczyk, M. (2024). A survey of Polish ASR speech datasets. Poznań Studies in Contemporary Linguistics 60(1), 27–52. [doi]
- Junczyk, M. (2023). BIGOS — Benchmark Intended Grouping of Open Speech Corpora for Polish ASR. FedCSIS 2023, Warsaw, 585–590. [pdf]
- Jeziorski, A., Sawicki, F., Solop, O., Junczyk, M., Sikora, M., & Zietkiewicz, T. (2020). Industrial ASR troubleshooting tool. LREC 2020 Industry Track, 10–14, ELRA. [pdf]
Talks
- 2026GenAI in Localization 2026
- 2026GenAI in Localization 2026
Run with Allegro's Localization & Data team.
- 2025Product Cafe #15
- 2025GenAI in Localization 2025
- 2024NeurIPS 2024 (D&B Track)
- 2024PolEval 2024
- 2024YouTube
- 2024Panel discussion (YouTube)
Teaching
AI Evaluation for Everyone — free online course for beginners and domain experts
Open course · 2026 — present · course
Workshops on speech recognition systems evaluation
Python for Linguists (IT Skills for Linguists)
AMU, English Philology dept. · 2022 — 2023 · materials
Introduction to Data Engineering
AMU, Mathematics and Computer Science dept. · 2020
Projects
- BIGOS V2 — Benchmark for Polish ASR
Curated benchmark grouping 24 open Polish speech corpora (BIGOS V2 and PELCRA for BIGOS) into a single, reproducible evaluation dataset. Published at NeurIPS 2024 (Datasets & Benchmarks Track).
- Polish ASR Leaderboard
Live public leaderboard ranking 25 speech-to-text systems on 4000+ Polish recordings — accuracy, cost, speed, and robustness.
- Polish ASR speech datasets catalog
Open catalog of speech datasets for Polish, intended for ASR systems development.
Community & service
- GenAI in Localization 20262026
Organizing committee [committee]
Skills
- Data-Centric ML systems design and development
- Data Annotation
- Data Engineering
- Automatic Speech Recognition
- Team management
- Project management
Awards
Best R&D Team Leader 2018 — recognized by the head of Samsung Research Institute Poland for contributions to the commercialization of voice assistants in European markets.
Languages
English, Polish
