In progress
PhD Thesis — Intertextuality & Causality
A semantic analysis of discourse that bridges NLP and formal methods: from echoes between migration narratives to causal relations in life stories, in text and, next, in speech.
01 · About
Who I am.
I grew up in Chad speaking a language with almost no digital footprint. Today I build the technology that gives languages like mine one. My research at CRIL-CNRS (UMR 8188) connects two worlds that rarely meet: discourse-level NLP and formal methods. I study how narratives echo one another and how causal structure can be extracted from them, with formal guarantees rather than heuristics.
A second thread runs alongside it: speech and multilingual evaluation. Having built speech and translation systems for African languages, I keep meeting the same problem: automatic metrics say very little about whether a model understood anything. That question drives my benchmark work, and I'm extending it to speech, starting with Chadian languages.
I teach algorithmics at Université d'Artois. On YouTube, Sakayo Tech brings AI education in French to students across francophone Africa, and my mentorship programme supports young innovators in Chad. I've worked with UNICEF, EPFL, CDIAL and Batazia, and I contribute to the Masakhane and AfricaNLP communities as a researcher and reviewer.
Low-resource speech (ASR/TTS)
Multilingual evaluation
Discourse & causality
Interpretable NLP
Lens, France
7peer-reviewed publications
2papers under review
145+students taught in Chad, Cameroon & France
2028PhD defence target
02 · News
Lately.
- Oct 2026Two papers under review: Beyond Separability at NAACL 2027 and FIRLAD at AAMAS 2027.
- Oct 2026Started year 2 of my PhD, and applying for 2027 research internships in speech and multilingual NLP.
- Aug 2026Presented Detecting Experiential Intertextuality Across Migration Routes as an oral at SIGDIAL 2026 (Atlanta, virtual). Paper · Code
- 2026Solo entry in the EvalLLM RAG Challenge at CORIA-TALN 2026, scoring above the field mean.
- Oct 2025Joined CRIL-CNRS as a PhD candidate on the ANR HYCI project, and started teaching Algorithms 2 at Université d'Artois.
03 · Current work
What I'm building.
SIGDIAL 2026
Experiential intertextuality
A new annotation-free task over 108 French migration narratives, validated on 816 expert-scored sentence pairs. A zero-shot LLM reaches 57% of the human noise ceiling, and a 31-feature hybrid reaches 69%.
PaperCodeUnder review
Beyond Separability
Adding a contrastive coverage loss to LoRA reshapes representation geometry at unchanged accuracy: silhouette scores rise on all six GLUE tasks, with gains on African languages. Three negative results are reported, not hidden.
Under review
FIRLAD — model-independent feature importance
Features ranked by their role in Minimal Support Sets from Logical Analysis of Data: one ranking whatever the classifier, linked to the Holler–Packel and Deegan–Packel power indices.
In revision
AfriCOPA
A diagnostic probe asking whether MT quality metrics track causal reasoning in African languages. They correlate with accuracy far more loosely than their use in evaluation assumes.
In revision
RF-LAD — compact formal explanations
Logical Analysis of Data built into random forest construction via Minimal Support Sets, producing abductive explanations roughly five times smaller than standard forests on microarray data.
CORIA-TALN 2026
EvalLLM RAG Challenge
Solo end-to-end French RAG pipeline built under strict compute constraints with open-weight models, scoring above the field mean.
Ongoing
Formal probing of language models
Probing with inclusion-minimality guarantees: which dimensions a model actually needs to encode a property, certified rather than estimated.
Ongoing
Decrypt AI — Sakayo Tech
AI education series in French for African students: concepts, careers and hands-on tools, published twice a week.
04 · Publications
Selected papers.
Under review
2027
Beyond Separability: Representation Geometry in Parameter-Efficient Fine-Tuning
NAACL 2027 via ACL Rolling Review · under review
2027
FIRLAD: Data-driven Feature Importance Through Logical Analysis of Data
AAMAS 2027 · under review
Published
2026 Detecting Experiential Intertextuality Across Migration Routes: Beyond Surface Similarity in French Narratives SIGDIAL 2026 · first author
2026
French RAG under Strict Constraints — EvalLLM Challenge
CORIA-TALN 2026
2025
Pretraining Strategies using Monolingual and Parallel Data for Low-Resource Machine Translation
AfricaNLP @ ACL 2025
2024
AfriMTE and AfriCOMET: Enhancing COMET to Embrace Under-resourced African Languages
NAACL 2024
2023
MasakhaNEWS: News Topic Classification for African Languages
IJCNLP-AACL 2023 · most-cited work
2023
Ngambay–French Neural Machine Translation (sba-Fr)
NLP4TIA @ RANLP 2023 · first author
2022
Error Correction Based Deep Neural Networks for Modeling and Predicting South African Wildlife–Vehicle Collision Data
Mathematics (MDPI)
Also published as Toadoum Sari Sakayo.
05 · Journey
From N'Djamena to Lens.
2026 — now
PhD Year 2 · CRIL-CNRS, Université d'Artois
SIGDIAL 2026 paper presented as an oral. Beyond Separability under review at NAACL 2027 and FIRLAD at AAMAS 2027. Teaching algorithmics, and building benchmarks for causal reasoning and speech in African languages.
2025
PhD begins · UNICEF · CDIAL
Joined CRIL on the ANR HYCI project. RCCE consultancy for UNICEF in Chad. Trained and evaluated ASR and TTS models for African languages at CDIAL, and ran a human evaluation with 20+ annotators.
2021 — 2023
AMMI · EPFL · Batazia · Tec4Tchad
African Master's in Machine Intelligence as a Google & Meta Scholar, with a thesis on Ngambay–French translation trained on Google Cloud through a Google research credit grant. DeepMind-funded data science programme at AIMS Rwanda. Research internship at EPFL on polarisation detection. NLP engineering at Batazia. Trained 40+ students in Python and ML in Chad.
2018 — 2020
AIMS Cameroon
MSc in Industrial Mathematics as a MasterCard Foundation Scholar, and my first paper.
2017 — 2019
Physics · Université de N'Gaoundéré
BSc in Applied Physics, then MSc in Physics. First steps in web development and ML at Limbe City Council.
06 · Skills
Tools I work with.
Research
Discourse semanticsCausal reasoning
Multilingual evaluationBenchmark design
Speech (ASR / TTS)Machine translation
Formal XAISAT / Logical Analysis of Data
RAG
Engineering
PythonPyTorch
Hugging FaceFine-tuning & LoRA
FastAPI
Infrastructure
Google Cloud · Vertex AIAWS SageMaker
SLURM clustersDocker
Git / GitHubLaTeX
07 · Contact
Let's talk.
Hosting a 2027 research intern in speech, multilingual NLP or evaluation? Building something for underserved languages, or want to collaborate on discourse, causality or African NLP? I'd love to hear from you.