Bartosz Chodnicki, Developer in Warsaw, Poland
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Bartosz Chodnicki

Verified Expert  in Engineering

Bio

Bartosz (Bart) is a passionate back-end developer who enjoys the challenge of creating high-traffic applications. He is a fan of building microservice applications with tight integrations to machine learning platforms and streaming processing to optimize business impact. His products handle hundreds of millions of active users and have high-scale push notifications and ML models that make predictions. He is happiest transforming ideas into apps and seeing users enjoy the tools he has built.

Portfolio

WisePatient
Python, Flutter, Node.js, React, Next.js, AWS Amplify, Amazon Cognito...
dotData
Scala, Akka, ZIO, PostgreSQL, Redis, OpenAI GPT-4 API...
DataLake
Scala, Akka, TypeScript, Solidity, Microservices, Google Cloud Platform (GCP)...

Experience

  • Microservices - 4 years
  • Scala - 3 years
  • Akka - 3 years
  • Cassandra - 2 years
  • Kubernetes - 2 years
  • Google Cloud Platform (GCP) - 2 years
  • Flink - 2 years
  • Play - 2 years

Availability

Part-time

Preferred Environment

Linux, IntelliJ IDEA, Scala, Apache Flink

The most amazing...

...tool I've developed is a streaming application based on Apache Flink that can detect "not nice" or "inappropriate" users.

Work Experience

CTO

2023 - PRESENT
WisePatient
  • Developed Android and iOS applications for patients.
  • Developed a web panel for clinics and physicians.
  • Oversaw the entire business as a co-founder.
Technologies: Python, Flutter, Node.js, React, Next.js, AWS Amplify, Amazon Cognito, Amazon DynamoDB, Amazon S3 (AWS S3), Firebase, Firebase Hosting, Firebase Authentication, Cloud Firestore, iOS, Android, Serverless Architecture, JavaScript, APIs, NoSQL, Architecture, Back-end, Stripe, Payment Gateways, TypeScript, Full-stack, API Integration, Databases, Full-stack Development, Web Development, Amazon Web Services (AWS), Algorithms, Data Science, Technical Leadership, Google Cloud, CSS, HTML, Dart, Front-end, Startups, Dashboards

Senior Developer

2023 - 2024
dotData
  • Proposed and created new functionalities based on ChatGPT.
  • Designed and led projects for new auto machine learning (ML) platform features.
  • Designed and created licensing mechanisms supporting very custom architectural specifications.
Technologies: Scala, Akka, ZIO, PostgreSQL, Redis, OpenAI GPT-4 API, Large Language Models (LLMs), Akka Actors, Python, Git, Jenkins, Streamlit, Amazon Web Services (AWS), Data Visualization, APIs, SQL, NoSQL, Architecture, Back-end, OpenAI API, API Integration, Databases, Algorithms, BigQuery, Data Science, OpenAI, Prompt Engineering, OpenAI GPT-3 API

Head of Development

2022 - 2023
DataLake
  • Designed, implemented, and maintained a web application for medical consents saved on the blockchain.
  • Collaborated closely with company co-founders to transform their business ideas into IT systems.
  • Assisted an external company in auditing our applications.
  • Created architecture for the data anonymization process.
  • Developed smart contracts and integrated them with our application.
  • Maintained infrastructure in the Google Cloud Platform (GCP).
Technologies: Scala, Akka, TypeScript, Solidity, Microservices, Google Cloud Platform (GCP), Kubernetes, Vault, Know Your Customer (KYC), Integration, Data Engineering, Webhooks, APIs, SQL, NoSQL, Architecture, Back-end, Node.js, React, Full-stack, API Integration, Databases, Full-stack Development, Web Development, Algorithms, Data Science, Technical Leadership, Google Cloud, HTML, Startups

Senior Scala Developer

2020 - 2022
GetInData
  • Developed microservices that handle hundreds of millions of active users.
  • Created streaming pipelines for real-time alerts.
  • Built an MLOps platform firmly integrated with other microservices.
Technologies: Scala, Play, Akka, Akka Actors, Akka Streams, Functional Programming, gRPC, REST, Apache Kafka, Cassandra, Redis, Elasticsearch, Kubernetes, Cloud, Google Cloud Platform (GCP), Prometheus, Grafana, Jenkins, Spinnaker, Flink, Machine Learning Operations (MLOps), CI/CD Pipelines, MLflow, Artificial Intelligence (AI), APIs, SQL, NoSQL, Architecture, Back-end, API Integration, Databases, Algorithms, BigQuery, Data Science, Google Cloud, Machine Learning, Dashboards

Senior Scala Developer

2020 - 2020
LogicAI
  • Developed web service that contain machine learning models used for making predictions.
  • Migrated and cleaned old repositories to newer technologies.
  • Completed benchmarks and tests of different technologies to meet client requirements.
Technologies: Scala, Akka, Akka Actors, Play, Spark, APIs, SQL, Back-end, TypeScript, API Integration, Databases, Algorithms, Data Science, Technical Leadership, Machine Learning, Artificial Intelligence (AI)

System Architect

2015 - 2019
IIIT
  • Designed and developed many services used for different marketing channels.
  • Developed a high-scale push notification system used for advertisement campaigns.
  • Designed and optimized databases used with our applications.
  • Analyzed network traffic with bot detection streaming algorithms.
  • Communicated with the business, planned project roadmaps, and worked in an Agile environment.
Technologies: Java, Python 3, PHP, Symfony, Django, Flask, Akka, Lua, Apache Kafka, MySQL, MongoDB, Redis, Pandas, Git, CI/CD Pipelines, Jenkins, Angular, Celery, Flink, eCommerce, Digital Marketing, APIs, SQL, NoSQL, Architecture, Back-end, JavaScript, TypeScript, Node.js, Full-stack, Springbot, API Integration, Databases, Full-stack Development, Web Development, Algorithms, Data Science, Technical Leadership, Machine Learning, Artificial Intelligence (AI), CSS, HTML, Front-end

Full-stack Developer

2011 - 2015
Orange
  • Developed a network quality monitoring system that allows the creation of different testing scenarios and presents results on a web platform.
  • Developed active robots based on the Linux operating system that allows network monitoring from an E2E perspective.
  • Deployed a network monitoring system in various European countries.
  • Contacted clients, gathered system requirements, planned the roadmap, and assisted with system usage.
Technologies: PHP, Linux, jQuery, APIs, SQL, Back-end, JavaScript, Full-stack, API Integration, Databases, Full-stack Development, Web Development, Algorithms, CSS, HTML, Front-end

Experience

ML Server with ZIO

https://github.com/bartchodnicki/zio-ml-server
This is an example of how to create an HTTP server for serving ML prediction with the ZIO HTTP library and MLeap. It enables the use of machine learning models made in Python or Spark with Scala applications. The project shows how to load the ML model saved in a file and use it to make predictions for incoming HTTP requests.

Education

2007 - 2012

Bachelor of Science Degree in Engineering of Informatics Systems

Warsaw University of Technology - Warsaw, Poland

Skills

Libraries/APIs

React, Akka Streams, Node.js, OpenAI API, jQuery, Pandas, ZIO, AWS Amplify, Stripe

Tools

Git, Flink, Jenkins, BigQuery, Celery, Grafana, IntelliJ IDEA, Vault, Amazon Cognito, Firebase Authentication

Languages

Scala, JavaScript, SQL, PHP, Python 3, TypeScript, Python, HTML, Dart, Java, Lua, Solidity, CSS

Frameworks

Play, Akka, Angular, Flutter, Next.js, Symfony, Django, Flask, Spark, gRPC, Streamlit

Paradigms

REST, Microservices, Functional Programming, Serverless Architecture

Platforms

Firebase, Linux, Apache Kafka, Kubernetes, Google Cloud Platform (GCP), Amazon Web Services (AWS), Spinnaker, Apache Flink, iOS, Android

Storage

MySQL, NoSQL, Databases, MongoDB, Redis, Cassandra, Google Cloud, Elasticsearch, PostgreSQL, Amazon DynamoDB, Amazon S3 (AWS S3), Cloud Firestore

Other

Software Development, Akka Actors, APIs, Architecture, Back-end, Full-stack, API Integration, Full-stack Development, Web Development, Algorithms, Technical Leadership, Startups, Cloud, Machine Learning, OpenAI GPT-4 API, Artificial Intelligence (AI), eCommerce, Data Science, OpenAI, Prompt Engineering, OpenAI GPT-3 API, Front-end, Dashboards, CI/CD Pipelines, Prometheus, HTTP, Machine Learning Operations (MLOps), MLeap, Know Your Customer (KYC), Integration, Data Engineering, Large Language Models (LLMs), Firebase Hosting, MLflow, Webhooks, Data Visualization, Digital Marketing, Payment Gateways, Springbot

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