Sergiu Mironescu
Senior Software Engineer | Python & Machine Learning
Salary / Daily rate
Barcelona, Spain
Freelance, open to permanent contract
Can come onsite
Skills
Languages
About me
Intro
Software Engineer with 6+ years building scalable web apps and ML trading systems. Led teams at Roche, increased productivity 25%, and created live crypto prediction models. Expert in Python, React, AWS, and neural networks - delivering high-performance solutions from concept to deployment.
Work experience
Software Developer / Technical Architect
Quantum ML Trading
Feb 2023 - May 2025
2 years 4 months
Barcelona · Remote
- Python - Tensorflow - Scikit-learn - Pandas / NumPy (Data Preprocessing) - Matplotlib / Plotly - Parallel Execution - Multi-thread - Stream - Logistic Regression, Random Forest, XGBoost, CatBoost - Neural Networks (MLP, LSTM, GRU, CNN) - Sentiment Models - Features Extraction (TSFresh / FeatureTools) - Optuna / Hyperopt DEMO - LIVE CHART: https://tunnel.pulsai.live/predictions_xgboost_live_multiple_5m_BTCUSDT.html
Software Engineer / Lead Software Engineer
Roche Diagnostics Europe
Nov 2021 - May 2023
1 year 7 months
Barcelona, Spain
- Python (Django, Pytest) - React JSX (Redux, React Testing Lib, Typescript) - AWS - Github / Github Actions - JIRA - Agile - Collaboration with external ML Company and medical Hospitals - Managed a dev team of 3 and increased ~25% productivity
React Native (Software Engineer/ Creator / Founder)
Moodem (proyecto propio)Freelance
Feb 2020 - Dec 2021
1 year 11 months
Barcelona, Spain
-React Native - Github - Javascript / Typescript - NodeJS - Websockets (socket.io) - Firebase (https://firebase.google.com/) - Sentry (https://sentry.io/welcome/) - Chat Module (Websockets) - Songs Module (Websockets) - Voting Songs System (Websockets) - Youtube Node Lib - Users Management (registration, login, profile) - XCode - Apple Deployment - Expo - Repo: https://github.com/xexiu/moodem
Javascript Developer / Engineering Lead – LATAM Office Expansion
Senior Javascript - Marfeel
Feb 2015 - Mar 2021
6 years 2 months
Las ramblas, 35, Barcelona · Hybrid
Marfeel provides a powerful reading experience on mobile that is designed to maximise engagement, expand readership and boost revenue for publishers and advertisers through the dynamic presentation of ads. - Javascript - HTML - CSS - JAVA - React Components - Metrics - Google Lighthouse - JIRA - Kibana - Prometheus - Pager Duty - Team Management - Led technical interviews and hiring decisions for backend, frontend, and QA roles - Conducted onboarding, mentoring, and technical training for the first wave of hires - Collaborated with HR and operations to set up infrastructure, tooling, and team structure in the new office. - Helped hire and onboard 10+ engineers within 2 months. - Reduced ramp-up time for new hires by 40% with structured onboarding and mentorship. - Established best practices and Git workflows used across the new office.
Front-end Full-Stack
McKinsey Social Initiative
Sep 2014 - Dec 2014
4 months
Sant Cugat del Vallès, Barcelona, Spain
Curso intensivo (duración de 4 meses) en el que se aprenden y se ponen en práctica tecnologías como: - HTML5 - CSS3 - SASS (RWD - Responsive Web Design) - Javascript - VCS (GIT) - Ruby (Ruby on Rails) - SQLite - Postgresql - TDD (Rspec) - Agile Methods - Soft-skills - MVC Empresas colaboradoras: Ironhack, KeyIntern, ESADE
Junior Web Developer
reinodemallorca.com
Mar 2011 - Jul 2014
3 years 5 months
Real Estate Page dedicated to sell and rent flats and houses ubicated on the Mallorca island. - HTML(5) - CSS(3)-SASS - PHP - GIT - MySQL - SEO/SEM - Community Manager - Sublime Text
Sales Manager
Apple
Dec 2010 - Dec 2011
1 year 1 month
Mexico City, CDMX, Mexico
Education
Ironhack
2014 - 2014
1 month
Seeway
Técnico Superior en Desarrollo y Programación Web
2012 - 2014
2 years 1 month
La Farga
Bachelor's degree
2002 - 2010
8 years 1 month