Mateusz Majchrzak - Senior Software Engineer

Q: Where is Mateusz based?

Mateusz is based in Warsaw, Poland .

Q: What languages does Mateusz speak?

Mateusz speaks the following languages: Polish (Native), English (Advanced) .

Q: How many years of experience does Mateusz have?

Mateusz has at least 12 years of experience. During this time, Mateusz has worked in at least 3 different roles and for 5 different companies . The average length of individual experience is 2 years and 4 months . Note that Mateusz may not have shared all experience and actually has more experience.

Q: What is Mateusz's latest experience?

Mateusz's most recent position is Senior Software Engineer at Ramp Network .

Q: What companies has Mateusz worked for in recent years?

In recent years, Mateusz has worked for Ramp Network , C&F , and IMAGINATION .

Q: Which industries is Mateusz most experienced in?

Mateusz is most experienced in industries like Information Technology (IT) , Banking and Finance , and Retail . Mateusz also has some experience in Media, Entertainment and Publishing .

Q: Which business areas is Mateusz most experienced in?

Mateusz is most experienced in business areas like Information Technology (IT) , Product Development , and Quality Assurance (QA) .

Q: Which industries has Mateusz worked in recently?

Mateusz has recently worked in industries like Information Technology (IT) , Banking and Finance , and Retail .

Q: Which business areas has Mateusz worked in recently?

Mateusz has recently worked in business areas like Information Technology (IT) , Product Development , and Quality Assurance (QA) .

Recommended expert

Warsaw, Poland

Experience

Nov 2022 - Present

3 years 5 months

London, United Kingdom

Senior Software Engineer

Ramp Network

Led the architecture and production deployment of deep learning NLP models, applying transformer architectures for voice-based assistants in a fintech environment.
Built semantic search pipelines using vector embeddings and retrieval-augmented generation (RAG) to improve support automation across user-facing platforms.
Designed and monitored evaluation systems for bot behavior, integrating custom interpretability modules and real-time dashboards for KPI tracking.
Applied MLOps best practices, integrating with GitHub Actions, Docker, and Terraform for CI/CD deployment of ML microservices.
Implemented monitoring frameworks using Prometheus and Grafana to ensure model stability and detect drift.
Translated research insights into performant, reproducible codebases using Jupyter Notebooks, Pytest, and LangChain.
Fine-tuned open-source LLMs via Hugging Face Transformers to handle ambiguous queries with context-aware fallback logic.
Championed model reproducibility, containerizing pipelines for retraining and rollback procedures across cloud stages.
Integrated multilingual support through dynamic prompt injection and real-time language detection pipelines.
Mentored junior developers on prompt engineering, evaluation strategies, and reliability-first ML system design.

Dec 2021 - Nov 2022

1 year

Warsaw, Poland

Senior Software Engineer

C&F

Spearheaded the development of a chat-based assistant for an NFT trading platform, optimizing NLP inference latency and accuracy.
Deployed and maintained Python-based ML services built with FastAPI and React, orchestrated via Docker Compose and AWS Lambda.
Developed a real-time model feedback loop, collecting user interactions to evaluate precision and recall metrics.
Leveraged Watson Assistant and Google NLP APIs to automate support workflows, reducing human intervention by 25%.
Built internal model comparison dashboards for evaluation against baseline QA systems using React and TailwindCSS.
Implemented automated testing suites with Cypress, Pytest, and ESLint to ensure system integrity pre-deployment.
Established cloud-first CI/CD ML workflows with Terraform and AWS ECS, reducing model rollout friction by 40%.
Introduced embedding similarity matching for real-time query ranking, reducing irrelevant results by 60%.
Developed and documented agent-based tools using OpenAI APIs, enabling multi-turn dialog strategies.
Applied FAISS and Pinecone for rapid vector search across knowledge bases, improving retrieval time for support agents.

Aug 2018 - Nov 2021

3 years 4 months

Warsaw, Poland

Software Engineer

IMAGINATION

Designed and deployed voice-first e-commerce assistants using Dialogflow ES, helping increase checkout completions on mobile.
Built intent-driven workflows with fallback recovery patterns to guide users through transactional flows seamlessly.
Constructed backend NLP orchestration layers using Node.js, supporting context management and entity resolution.
Developed NLU training pipelines integrated with form-based user flows, fine-tuned for platform-specific vocabulary.
Applied semantic text analysis with custom scoring metrics to evaluate input quality and bot understanding.
Built hybrid mobile modules using React Native, synchronizing user state with dynamic chat UX components.
Performed weekly audits using Watson NLP metrics, increasing bot accuracy by 28% over six months.
Championed the introduction of automated regression tests for conversational flows via Vitest.
Co-authored internal whitepaper on intent mapping architectures and dynamic slot-filling techniques.
Reduced friction in multilingual transitions by implementing real-time translation middleware.

Aug 2016 - Jul 2018

2 years

Warsaw, Poland

Software Engineer

Order Group

Built early NLP integrations in Laravel-based admin tools, enabling voice-guided reporting and status summaries.
Developed a lightweight text classification pipeline for categorizing system alerts and prioritizing them in dashboards.
Created JWT-secured endpoints to serve chatbot data from internal systems using RESTful JSON APIs.
Designed adaptive admin UIs using React.js, configured to respond to voice-triggered intents via bots.
Integrated chatbot support into WordPress portals, enriching legacy apps with AI-driven assistance.
Collaborated with PMs to define user stories tied to AI enhancements across B2B portals.
Delivered auto-reply engines using rule-based inference and fallback ML classification.
Tracked bot engagement trends across enterprise clients using Cloudflare Analytics and Sentry.
Conducted voice assistant experiments with command-based shortcuts for enterprise dashboards.
Co-developed internal semantic tag engine to detect domain-specific language in tickets and conversations.

Sep 2014 - Sep 2016

2 years 1 month

Warsaw, Poland

Web Developer

Fuero Games

Maintained and enhanced web applications built with PHP, HTML5, CSS3, and JavaScript.
Created responsive UIs that later served as base structures for chatbot UI experiments.
Integrated third-party APIs and tracked user events to improve site behavior prediction models.
Began experimentation with voice UI components embedded in web apps.
Built CMS extensions for WordPress and Joomla with intent-driven UX workflows.
Supported bug tracking and hotfix pipelines via GitHub and Jira.
Developed internal tools for CMS behavior tagging and voice-enabled FAQs.
Conducted performance profiling using Chrome DevTools and Lighthouse.
Laid foundational code for secure input handling and token-based sessions.
Integrated simple REST endpoints to fetch knowledge base content dynamically.

Industries Experience

See where this freelancer has spent most of their professional time. Longer bars indicate deeper hands-on experience, while shorter ones reflect targeted or project-based work.

Experienced in Information Technology (9.5 years), Banking and Finance (3.5 years), Retail (3.5 years), and Media and Entertainment (2 years).

Information Technology

Banking and Finance

Retail

Media and Entertainment

Business Areas Experience

The graph below provides a cumulative view of the freelancer's experience across multiple business areas, calculated from completed and active engagements. It highlights the areas where the freelancer has most frequently contributed to planning, execution, and delivery of business outcomes.

Experienced in Information Technology (11.5 years), Product Development (11.5 years), and Quality Assurance (4.5 years).

Information Technology

Product Development

Quality Assurance

Summary

Senior Software Engineer with over 10 years of experience architecting, training, and deploying production-grade machine learning systems across healthcare, fintech, and conversational AI domains. Adept at bridging the research-to-production gap, I specialize in building deep learning pipelines, transformer-based NLP models, and MLOps workflows that scale across cloud environments. With a strong foundation in statistical learning, real-time model evaluation, and CI/CD automation, I bring a rare blend of curiosity, reproducibility discipline, and systems thinking to ML engineering. Recognized for designing robust, interpretable models and implementing semantic search and agent-based systems aligned with real-world applications.

Skills

Languages

Python
Javascript
Typescript
Php
Sql
Yaml
Json
Bash
Scss
Html5
Css3

Ml & Ai Libraries

Tensorflow
Pytorch
Scikit-learn
Xgboost
Lightgbm
Spacy
Nltk
Hugging Face Transformers
Sentence-transformers
Openai
Langchain
Fasttext
Pandas
Numpy
Matplotlib
Seaborn
Pydantic
Mlflow

Llms & Semantic Search

Gpt-4
Gpt-3.5
Rag
Faiss
Pinecone
Weaviate
Bm25
Tf-idf
Elasticsearch
Bert
Roberta
Openai Apis
Langchain Agents

Frameworks & Tools

Fastapi
Flask
Node.js
Nestjs
Express.js
Laravel
Django
Apollo
Rest
Graphql
Websockets
Trpc
Next.js
React
Vue.js

Cloud & Deployment

Aws Lambda
Aws Ecs
Aws S3
Aws Cloudwatch
Aws Fargate
Azure Functions
Gcp
Docker
Kubernetes
Jenkins
Github Actions
Mlflow
Airflow

Vector Dbs & Data Infra

Faiss
Pinecone
Chromadb
Postgresql
Mysql
Redis
Mongodb
Supabase
Prisma
Sequelize

Monitoring & Testing

Sentry
Prometheus
Grafana
Pytest
Jest
Cypress
React Testing Library
Vitest

Productivity & Visualization

Jupyter
Streamlit
Dash
Plotly
Figma
Jira
Slack
Zeplin

Apis & Sdks

Openai Sdk
Google Maps Api
Stripe Api
Github Api
Langchain
Restful Apis
Graphql Apis

Methods & Workflow

Agile
Scrum
Kanban
Tdd
Dora Metrics
Rfcs
Adrs
Git Flow

Languages

Polish

Native

English

Advanced

Education

Oct 2011 - Jun 2015

Polish-Japanese Academy of Information Technology

Bachelor's degree, Computer Science · Computer Science · Warsaw, Poland

Profile

Created

December 2025

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Frequently asked questions

Do you have questions? Here you can find further information.

Where is Mateusz based?

Mateusz is based in Warsaw, Poland.

What languages does Mateusz speak?

Mateusz speaks the following languages: Polish (Native), English (Advanced).

How many years of experience does Mateusz have?

Mateusz has at least 12 years of experience. During this time, Mateusz has worked in at least 3 different roles and for 5 different companies. The average length of individual experience is 2 years and 4 months. Note that Mateusz may not have shared all experience and actually has more experience.

What roles would Mateusz be best suited for?

Based on recent experience, Mateusz would be well-suited for roles such as: Senior Software Engineer, Software Engineer, Web Developer.

What is Mateusz's latest experience?

Mateusz's most recent position is Senior Software Engineer at Ramp Network.

What companies has Mateusz worked for in recent years?

In recent years, Mateusz has worked for Ramp Network, C&F, and IMAGINATION.

Which industries is Mateusz most experienced in?

Mateusz is most experienced in industries like Information Technology (IT), Banking and Finance, and Retail. Mateusz also has some experience in Media, Entertainment and Publishing.

Which business areas is Mateusz most experienced in?

Mateusz is most experienced in business areas like Information Technology (IT), Product Development, and Quality Assurance (QA).

Which industries has Mateusz worked in recently?

Mateusz has recently worked in industries like Information Technology (IT), Banking and Finance, and Retail.

Which business areas has Mateusz worked in recently?

Mateusz has recently worked in business areas like Information Technology (IT), Product Development, and Quality Assurance (QA).

What is Mateusz's education?

Mateusz holds a Bachelor in Computer Science from Polish-Japanese Academy of Information Technology.

What is the availability of Mateusz?

Mateusz is immediately available full-time for suitable projects.

What is the rate of Mateusz?

Mateusz's rate depends on the specific project requirements. Please use the Meet button on the profile to schedule a meeting and discuss the details.