Sachith Gunasekara
Hi! I’m Sachith, a Senior AI Engineer at Gapstars, working with Envision AI Labs in Leiden, Netherlands. Most of my days revolve around one question: how do we know an AI system is actually good? I build retrieval benchmarks and evaluation frameworks for RAG and agentic systems, and I make sure every insight we generate from pharmaceutical and clinical data can be traced back to its source. Before this, I built multi-agent systems at Arcadea Group and Surge Global, after graduating at the top of my class (First Class, ranked 1st of 125) in Computer Science from the University of Kelaniya.
On the research side, I’m fascinated by how language models reason, and how we can help them reason better without simply throwing more compute at the problem. My latest work, iSelf-Discover, asks a deceptively simple question: should a model plan its reasoning in structured JSON or in plain language? Plain language won, by up to 18.9% on MATH. Before that, I helped build OpenBezoar, a recipe for training small, open instruction-following models on a modest budget.
I love sharing what I learn. I teach on StemLink’s AI Engineering Bootcamp, where I get to watch learners go from their first transformer to working multi-agent demos. I’ve also given talks such as A Step Beyond the Hype and Implementing AI Agents, and I write the occasional deep dive, like nanoJAXGPT, a hands-on introduction to JAX/Equinox. Looking ahead, I’m keen to pursue a PhD in Computer Science focused on making LLMs reason better and more efficiently. If that overlaps with what you’re working on, I’d love to chat!
news
| Feb 01, 2026 Industry | Joined Gapstars as a Senior AI Engineer, placed at Envision AI Labs (Leiden, Netherlands) |
|---|---|
| Sep 01, 2025 Teaching & Talks | Started teaching as an Instructor on the StemLink AI Engineering Bootcamp |
| Aug 01, 2025 Awards & Honours | Selected as a Youth Delegate for the Global Leadership Program at Brasenose College, University of Oxford |
| Jul 01, 2025 Research | Released our pre-print Effects of structure on reasoning in instance-level Self-Discover on arXiv |
| Jun 01, 2025 Industry | Joined Arcadea Group (Toronto, Canada) as a Senior AI Engineer |
| Apr 01, 2025 Teaching & Talks | Gave an invited talk, A Step Beyond the Hype: A Journey Through Modern AI, at the IEEE Student Branch, Wayamba University of Sri Lanka |
| Apr 01, 2025 Industry | Promoted to Machine Learning Engineer at Surge Global |
| Oct 23, 2024 Research | Published nanoJAXGPT: A pedagogical introduction to JAX/Equinox on the Hugging Face blog (code) |
| Oct 01, 2024 Community | Served as a Judge at Sri Lanka Artificial Intelligence Competition (SLAIC) 2024, IEEE Young Professionals Sri Lanka Section |
| Aug 01, 2024 Teaching & Talks | Delivered an invited workshop, Implementing AI Agents, for university undergraduates at AI-Driven Sri Lanka |
| Apr 01, 2024 Research | Released our pre-print OpenBezoar: small, cost-effective and open models trained on mixes of instruction data on arXiv |
| Mar 27, 2024 Awards & Honours | Awarded Gold medal for best performance in Computer Science in the Faculty of Science, University of Kelaniya at the 142nd General Convocation |
| Dec 01, 2023 Community | Served as a Mentor for an AI Bootcamp final competition at IEEE Young Professionals - Sri Lanka |
| Oct 13, 2023 Awards & Honours | Recognized as the Best Presenter at the 4th International Conference on Applied and Pure Sciences (ICAPS 2023) - Kelaniya |
| Oct 01, 2023 Industry | Promoted to Associate Machine Learning Engineer at Surge Global |
| Jul 01, 2023 Education | Graduated at the top of the class from the University of Kelaniya with a Bachelor of Science Honours Degree in Computer Science (First Class Division) |
| Mar 13, 2023 Industry | Joined Surge Global as a Data Science Intern |
| Feb 02, 2023 Awards & Honours | Received Dean’s List award for Academic Year 2019/2020 at University of Kelaniya |
| Jan 29, 2023 Awards & Honours | Received Dean’s List award for Academic Year 2020/2021 at University of Kelaniya |
| Nov 15, 2022 Awards & Honours | Achieved Second Prize at the IEEE SA P2834 Student Challenge 2022, Valencia, Spain |
| Jul 19, 2021 Education | Was selected for the specialized Computer Science Honours program at the University of Kelaniya based on exceptional academic performance |
| Feb 19, 2021 Awards & Honours | Received Dean’s List award for Academic Year 2017/2018 at University of Kelaniya |
| Feb 14, 2019 Education | Secured admission to the Bachelor of Science program at the University of Kelaniya, Sri Lanka |
latest posts
selected publications
- Extended AbstractCapturing sentence-level positional data into N-gram profiles for document classificationICAPS, Faculty of Science, University of Kelaniya, Sri Lanka, Apr 2023