Software Engineer · Prague

Machine Learning
& Audio Processing

I build intelligent systems — from fine-tuning LLMs and training audio models to deploying production ML pipelines. 7+ years of software engineering with a focus on bringing research to real-world applications.

Lukas Starenko

Background

I started my career in .NET enterprise development — building CRM integrations, reporting systems, and Azure-hosted applications for clients in banking, automotive, and tourism.

Over time, I shifted toward machine learning. Today I work on LLM fine-tuning, transformer-based audio models, and ML classification tools.

I write about my experiments on Medium and I'm always looking for interesting problems at the intersection of software engineering and machine learning.


What I focus on

ML & LLM Fine-tuning

Training and adapting large language models for specific domains. Local deployment and optimization for production use.

PyTorch Llama Mistral Qwen Transformers

Audio Processing

Audio ML pipelines — classification, generation. Transformer-based architectures for audio.

Mel Spectrograms MFCC HuBERT ContentVec torchaudio librosa

Cloud

Production-grade APIs and cloud infrastructure. Strong .NET ecosystem background with Azure services.

.NET Core Python FastAPI Azure Docker PostgreSQL

Programming

Strong foundation in software development — clean code, algorithms, data structures, and object-oriented design.

Python C# Algorithms OOP Git

Where I've worked

2024 — Present

ML Engineer

Freelance

Fine-tuning local LLMs for educational apps. ML classification tools for audio engineers. Conversational chatbots for Czech e-commerce.

LLMAudio MLPyTorchReact
2023 — 2024

.NET Developer

AIMTEC a.s.

Built a reporting SPA from scratch. Domain-driven design backend hosted on Azure.

C# .NETEF CoreAzure
2022 — 2023

Python Developer

Open-IT cz, s.r.o.

Tourism prediction app backend. NetLogo simulation integration with university researchers.

PythonDockerNetLogo
2021 — 2022

.NET Developer

ACMARK s.r.o.

Banking CRM integrations. Azure Functions, SSRS reports, MS Dynamics customization.

C# .NETMS DynamicsAzure Functions
2020 — 2021

.NET / Dynamics Developer

ORTEX spol. s r.o.

MS Dynamics CRM plugin development. Customer requirements analysis.

C# .NETMS Dynamics CRM
2018 — 2020

PHP / C# Developer

AUTMES

Attendance system in PHP/Nette. WinForms maintenance app in C#.

PHPC# .NET

Selected work

ML · Audio

Audio Processing Pipeline

ML classification tools for audio engineers using transformer-based models. Architecture experiments to improve production accuracy.

TransformersAudio MLClassification
ML · Education

English Teacher LLM

Fine-tuning local LLMs for an educational app for older adults. Recommendation algorithms and React frontend.

LlamaMistralFine-tuning
ML · Trading

Algorithmic Trading

4+ years building strategies with Freqtrade. GBDT models via FreqAI for crypto market prediction and automated decisions.

FreqAIGBDTPython
NLP · E-commerce

Czech E-shop Chatbot

Conversational chatbot for a Czech e-shop recommending products using a local LLM with optimized prompt engineering.

LLMPrompt Eng.Chatbot

Audio Embedding Visualization

Use case: Visualized audio embeddings help us build balanced datasets by revealing class distributions and identifying underrepresented samples.

Each point represents a speech sample from one of 7 European languages. Audio files are converted into 768-dimensional embeddings using a ContentVec transformer model, then projected into 3D space with UMAP. The resulting clusters show that the model captures language-specific acoustic patterns — similar languages appear closer together.

Model: ContentVec (768-dim) Reduction: UMAP → 3D Dataset: Multilingual LibriSpeech Samples: 15,086 across 7 languages

Let's talk

Open to ML engineering roles, freelance projects, and interesting collaborations.