Recommended expert

Mateusz Majchrzak

Senior Software Engineer

Mateusz Majchrzak
Warsaw, Poland

Experience

Nov 2022 - Present
3 years 3 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.

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

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