Recent & Upcoming Talks

From Brittle LLM Code Reasoning to MaxSAT-Based Verified Repairs @ UCL featured image

From Brittle LLM Code Reasoning to MaxSAT-Based Verified Repairs @ UCL

In this talk, we examine the limitations of Large Language Models (LLMs) in semantic code reasoning, showing that their predictions may change under semantics-preserving code …

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Pedro Orvalho
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Towards Assessing and Repairing LLM-Generated Code via Model Checking and MaxSAT-Based Fault Localisation @ Dagstuhl 2026 featured image

Towards Assessing and Repairing LLM-Generated Code via Model Checking and MaxSAT-Based Fault Localisation @ Dagstuhl 2026

LLMs for code often lack true semantic understanding, evidenced by their instability under semantics-preserving transformations, and we address this by integrating formal methods …

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Pedro Orvalho
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PyVeritas: On Verifying Python via LLM-Based Transpilation and Bounded Model Checking for C @ P-AI-FM@AAAI 2026 featured image

PyVeritas: On Verifying Python via LLM-Based Transpilation and Bounded Model Checking for C @ P-AI-FM@AAAI 2026

In this talk I will present PyVeritas, a novel framework that leverages Large Language Models (LLMs) for high-level transpilation from Python to C, followed by bounded model …

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Pedro Orvalho
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MENTOR: Fixing Introductory Programming Assignments With Formula-Based Fault Localization and LLM-Driven Program Repair @ INESC-ID featured image

MENTOR: Fixing Introductory Programming Assignments With Formula-Based Fault Localization and LLM-Driven Program Repair @ INESC-ID

In this talk, I will present my PhD work on MENTOR, a semantic automated program repair framework designed to provide meaningful feedback for introductory programming assignments.

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Pedro Orvalho
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From Logic to Learning: Rethinking Programming for the AI Era @ DEI, IST-UL featured image

From Logic to Learning: Rethinking Programming for the AI Era @ DEI, IST-UL

In this talk, I will present approaches that leverage the precision of formal logic and the adaptability of learning-based models to enable intelligent code generation, automated …

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Pedro Orvalho
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Counterexample Guided Program Repair Using Large Language Models and MaxSAT-based Fault Localization @ IIIA-CSIC featured image

Counterexample Guided Program Repair Using Large Language Models and MaxSAT-based Fault Localization @ IIIA-CSIC

In this talk I will present a hybrid method to automated repair of C code, using Maximum Satisfiability (MaxSAT)-based fault localization, CFaults, to localize bugs and LLMs to …

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Pedro Orvalho
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Are Large Language Models Robust in Understanding Code Against Semantics-Preserving Mutations? @ Oxford featured image

Are Large Language Models Robust in Understanding Code Against Semantics-Preserving Mutations? @ Oxford

In this talk, I will present our evaluation on whether state-of-the-art LLMs with up to 8B parameters can reason about Python programs or are simply guessing.

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Pedro Orvalho
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MENTOR: Automated Feedback for Introductory Programming Exercises @ FCT-UNL featured image

MENTOR: Automated Feedback for Introductory Programming Exercises @ FCT-UNL

In my talk, I will present MENTOR, a semantic automated program repair (APR) framework designed to provide Automated Feedback for Introductory Programming Exercises.

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Pedro Orvalho
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MENTOR: Feedback Automático para Exercícios Introdutórios de Programação (Portuguese) @ VoA 2025 featured image

MENTOR: Feedback Automático para Exercícios Introdutórios de Programação (Portuguese) @ VoA 2025

Nesta palestra, irei apresentar o sistema MENTOR, uma ferramenta de reparação automática de programas orientada para fornecer feedback automatizado para exercícios introdutórios de …

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Pedro Orvalho
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Counterexample Guided Program Repair Using Zero-Shot Learning and MaxSAT-based Fault Localization @ OutSystems featured image

Counterexample Guided Program Repair Using Zero-Shot Learning and MaxSAT-based Fault Localization @ OutSystems

In this talk I will present our novel approach that combines the strengths of both FM-based fault localization and LLMs, via zero-shot learning, to enhance Automated Program …

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Pedro Orvalho
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GitSEED: A Git-backed Automated Assessment Tool for Software Engineering and Programming Education @ SIGCSE-Virtual 2024 featured image

GitSEED: A Git-backed Automated Assessment Tool for Software Engineering and Programming Education @ SIGCSE-Virtual 2024

In this talk I will present GitSEED, a language-agnostic automated assessment tool designed for Programming Education and Software Engineering (SE) and backed by GitLab.

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Pedro Orvalho
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LLM-Driven Automated Program Repair Using MaxSAT-based Fault Localization @ Oxford featured image

LLM-Driven Automated Program Repair Using MaxSAT-based Fault Localization @ Oxford

In this talk I will present a hybrid method to automated repair of C code, using Maximum Satisfiability (MaxSAT)-based fault localization, CFaults, to localize bugs and LLMs to …

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Pedro Orvalho
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CFaults: Model-Based Diagnosis for Fault Localization in C with Multiple Test Cases @ FM 2024 featured image

CFaults: Model-Based Diagnosis for Fault Localization in C with Multiple Test Cases @ FM 2024

In this talk I will introduce a novel fault localization approach for C programs with multiple faults. CFaults leverages Model-Based Diagnosis (MBD) with multiple observations and …

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Pedro Orvalho
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C-Pack of IPAs: A C90 Program Benchmark of Introductory Programming Assignments @ APR@ICSE 2024 featured image

C-Pack of IPAs: A C90 Program Benchmark of Introductory Programming Assignments @ APR@ICSE 2024

In this talk I will present C-Pack-IPAs, a publicly available benchmark comprising student-program submissions for 25 distinct introductory programming assignments (IPAs).

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Pedro Orvalho
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UpMax: User partitioning for MaxSAT @ SAT 2023 featured image

UpMax: User partitioning for MaxSAT @ SAT 2023

In this talk I will present a new framework called UpMax that decouples the partitioning procedure from the MaxSAT solving algorithms.

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Pedro Orvalho
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Learning Variable Mappings to Repair and Verify Programs @ CIIRC 2023 featured image

Learning Variable Mappings to Repair and Verify Programs @ CIIRC 2023

In this talk I will propose using graph neural networks (GNNs) to map the set of variables between two programs based on both programs' abstract syntax trees (ASTs).

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Pedro Orvalho
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