Hello! I’m Charlie

I’m a doctoral researcher in the Computer Science department at Aalto University. My Ph.D. dissertation contributes methods to automate programming feedback using open-source language models, with a focus on supporting novice programmers in large-scale learning environments where individual feedback is hard to scale.

The broader goal of my research is to move beyond systems that rely on large language models and instead build lightweight, locally deployable learning tools powered by small models. My work blends reinforcement learning and source code modelling approaches with knowledge from programming education to effectively support students.

Recent News

15 September 2025
Two papers accepted at SIGCSE TS 2026!

• Aligning Small Language Models for Programming Feedback: Towards Scalable Coding Support in a Massive Global Course (first author)
• Fine-Tuning Open-Source Models as a Viable Alternative to Proprietary LLMs for Explaining Compiler Messages (second author)

27 May 2025
Our paper “Reinforcement Learning for Programming Feedback: Aligning Small Language Models Without Human Preferences” (first author) has been accepted to CSEDM 2025.

24 May 2025
Great news! Our paper “Direct Repair Optimization: Training Small Language Models for Educational Program Repair Improves Feedback Abilities” (first author) has been accepted to BEA 2025.

2 May 2025
I presented my recent research at Berkeley’s ACE Lab, focusing on feedback generation with small language models.

1 April 2025
I’m currently visiting the Piech Lab at Stanford University through June 2025.