Machine Learning Engineer · Zürich, Switzerland

Zohreh
Mostaani

I build and validate machine-learning pipelines end to end; from data acquisition and signal preprocessing to modeling and rigorous evaluation. I work mainly with speech and physiological signals, with a recent focus on automated evaluation for generative, LLM-driven speech systems.

Zohreh Mostaani
7+
years building ML
15+
publications
~700
citations
9
h-index
01

About

I'm a Machine Learning Engineer with a PhD from EPFL and 7+ years building deep learning and time-series ML pipelines end to end; from data acquisition and signal preprocessing to modeling and rigorous, often automated, evaluation. Most of my work is with speech and physiological signals, and I've recently focused on evaluation and tooling for generative, LLM-driven speech systems. I work in Python with PyTorch, TensorFlow, and scikit-learn, and build reproducible pipelines with Docker, REST APIs, and automated tests. Along the way I've collected specialized speech, physiological, and face/voice datasets, mentored Master's students, and reviewed for IEEE/ACM Transactions on Audio, Speech, and Language Processing.

02

Selected work

Generative speech · Evaluation

Automated TTS evaluation framework

Benchmarked 9 text-to-speech voices across 15 domains into a single quality score from intelligibility, audio quality, speaker similarity, and synthesis success, cutting reliance on manual listening tests. Validated against a human ranking study, with automatic and human rankings agreeing on the top-3 and bottom-2 voices.

Speech · Deep learning

Breathing signals from raw speech

Developed deep-learning models that estimate breathing signals directly from raw speech waveforms in TensorFlow, achieving a 25% reduction in input lag compared with spectral-based models.

Radar · Time series

Non-contact vital-sign monitoring

Developed a distance-bin detection method that reduced MSE by ~50% versus a fixed-bin baseline, then fed the detected bins into an existing ML model for vital-sign estimation, cutting downstream errors by ~31% (breathing rate) and ~87% (heart rate).

Speech · Health

Health models from speech

Developed models for COVID-19 detection, emotion recognition, heart-rate estimation, and hypoglycemia detection in diabetic patients, using speech signals with both data-driven and hand-crafted features in PyTorch and scikit-learn.

Biometrics · Computer vision

Face biometrics & anti-spoofing

Investigated presentation attacks on CNN-based face-recognition systems, including makeup-induced spoofing, and collected and curated two large face-biometric datasets from 100+ participants, including acquisition protocol design and attack generation.

Hackathon · EPFL · 2025

AI for children's reading assessment

At the Lemanic Life Science Hackathon at EPFL, worked with a multidisciplinary team on a prototype to help clinicians assess children's reading. Selected WavLM base+ for phoneme recognition on children's speech and built the initial pipeline; the team reached a working prototype in three days.

03

Experience

Jan 2026 – Jun 2026

Research Engineer

AGIGO AG · Zürich, Switzerland
Generative speech evaluation for an agentic, LLM-driven conversational AI platform.
  • Built an automated framework to benchmark 9 TTS voices across 15 domains into a single quality score, validated against a human ranking study.
  • Designed a diagnostic report that localizes TTS errors via an ASR round-trip, classifying mismatches by severity for fast debugging.
  • Packaged the framework as a Dockerized microservice with HTTP endpoints, integrated into the team's model-evaluation workflow.
Jul 2025 – Oct 2025

Machine Learning Engineer – BNF Project

Sleepiz AG · Zürich, Switzerland
Radar signal processing and ML pipeline.
  • Designed and ran data-collection protocols for radar-based, non-contact human detection and vital-sign monitoring.
  • Developed a distance-bin detection method (signal processing and filtering) that reduced MSE by ~50% versus the default fixed-bin baseline.
  • Fed the detected bins into an existing ML model for vital-sign estimation, cutting downstream errors versus the fixed-bin baseline by ~31% for breathing rate and ~87% for heart rate.
Feb 2020 – Dec 2024

Research Assistant – Speech & Audio Processing

Idiap Research Institute · Martigny, Switzerland
Integrating physiological signals into speech-processing technologies with machine and deep learning.
  • Developed deep-learning models to estimate breathing signals from raw speech (TensorFlow), with a 25% reduction in input lag vs. spectral models.
  • Built hypoglycemia-detection and heart-rate-estimation models from speech and physiological signals, and worked on COVID-19 detection and emotion recognition; ran speaker-dependent and speaker-independent evaluations.
  • Designed acquisition protocols and collected two databases of simultaneous speech and physiological recordings from 54 participants (22 in clinical settings).
  • Mentored two Master's students through internships and theses; teaching assistant for Machine Learning and Introduction to Speech Processing.
Apr 2019 – Jan 2020

Research & Development Engineer – Biometrics, Security & Privacy

Idiap Research Institute · Martigny, Switzerland
  • Investigated presentation attacks on CNN-based face-recognition systems, including makeup-induced spoofing.
  • Rewrote and restructured the documentation for the BEAT ML-experimentation framework (Python, Django, Sphinx), making an outdated platform usable again; QA-tested it across experiment execution and usability, and reported and fixed bugs.
  • Devised a protocol for collecting face-biometric data in automotive environments.
Jun 2016 – Mar 2019

Research Internships

Idiap Research Institute · Martigny, Switzerland
  • Collected two large face-biometric datasets from 100+ participants, including acquisition protocol design and presentation-attack generation.
  • Integrated an ASR system into a web framework using Docker and a RESTful API.
  • Implemented a CNN for gaze estimation in Theano.
Feb 2012 – Jan 2015

Research Assistant

Özyeğin University · Istanbul, Turkey
  • Improved signal-to-noise ratio in free-space optical communication by 50% using multiple relays.
  • Ran assignments, labs, and exams for Physics, Mathematics, Linear Algebra, and Wireless Communications.
04

Selected publications

Neural Networks · 2021 Deep Learning Architectures for Estimating Breathing Signal and Respiratory Parameters from Speech Recordings
V. S. Nallanthighal, Z. Mostaani, A. Härmä, H. Strik, M. Magimai-Doss
ICASSP · 2021 On the Relationship Between Speech-Based Breathing Signal Prediction Evaluation Measures and Breathing Parameters Estimation
Z. Mostaani, V. S. Nallanthighal, A. Härmä, H. Strik, M. Magimai-Doss
INTERSPEECH · 2022 On Breathing Pattern Information in Synthetic Speech
Z. Mostaani, M. Magimai-Doss
Diabetes Care · 2026 Listening to Hypoglycemia: Voice as a Biomarker for Detection of a Medical Emergency Using Machine Learning
V. Lehmann, M. Hilpert, Z. Mostaani, S. Hovsepyan, E. Wallace, C. Verzat, et al.
IEEE Trans. Information Forensics & Security · 2020 Biometric Face Presentation Attack Detection with Multi-Channel Convolutional Neural Network
A. George, Z. Mostaani, D. Geissenbuhler, O. Nikisins, A. Anjos, S. Marcel
IEEE Trans. Biometrics, Behavior & Identity Science · 2022 Domain-Specific Adaptation of CNN for Detecting Face Presentation Attacks in NIR
K. Kotwal, S. Bhattacharjee, P. Abbet, Z. Mostaani, et al.

Full list – 15+ publications, ~700 citations, h-index 9 – on Google Scholar →

05

Education & research

PhD, Electrical & Electronics Engineering
EPFL · with Idiap Research Institute
2025
M.Sc., Electrical & Electronics Engineering
Özyeğin University
2015
B.Sc., Electrical Engineering
University of Tehran
2011

Selected talks & conferences

ICASSP 2022IEEE Int'l Conf. on Acoustics, Speech & Signal Processing · Singapore
INTERSPEECH 2022Incheon, Korea
INTERSPEECH 2024Kos Island, Greece
Valais AI Workshop 2022Technopôle, Sierre, Switzerland
NCCR Summer School 2023Grindelwald, Switzerland
06

Skills

Languages & tools

PythonNumPyPandasSciPyMATLABShellGit

Deep learning & ML

PyTorchTensorFlowscikit-learnCNN / RNN / TCNTransformers & attentionTime-series modelingFeature engineeringEvaluation & ablation

Speech & signals

TTS / synthesis evaluationSpeech quality (MOS)ASR integrationRadar signal processingPhysiological signals

ML engineering & systems

DockerFastAPI / Flaskconda / mambaPoetryuvAWSAzureClaude Code

Data & evaluation

Dataset design & collectionLabeling protocolsData pipelinesHuman evaluation / A-B testingMatplotlib · Seaborn · Plotly

Spoken languages

English: fluentFrench: intermediatePersian: native

Let's work together

I'm open to Machine Learning Engineer, Applied Scientist, and Research Engineer roles in the Zürich area. The fastest way to reach me is email.