Tomasz Posłuszny, Developer in Warsaw, Poland
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Tomasz Posłuszny

Verified Expert  in Engineering

Bio

Tom is a seasoned full-stack software engineer and solutions architect who specializes in Chromium projects. With experience ranging from Fortune 500 companies to agile startups, he excels in navigating complex native codebases, web technologies, and multiprocess and multithreaded systems. As a lead software engineer, Tom has also taken on project management responsibilities, giving him unique insights into team assembly and project oversight.

Portfolio

Diffbot
Node.js, Express.js, Chrome DevTools Protocol, Chromium, Web Scraping...
Skyrocket Tech Inc
C++, Chromium, Python, JavaScript, TypeScript, Amazon Web Services (AWS), MacOS...
Goldman Sachs
Java 11, Java, Kubernetes, Docker, GitLab CI/CD, GitLab, Apache JMeter, JVM...

Experience

  • C++ - 8 years
  • JavaScript - 7 years
  • Software Design - 7 years
  • Chromium - 6 years
  • Python - 5 years
  • Software Architecture - 4 years
  • Amazon Web Services (AWS) - 3 years
  • Technical Leadership - 3 years

Availability

Part-time

Preferred Environment

Shell Scripting, Visual Studio Code (VS Code), Microsoft Visual Studio

The most amazing...

...digital product I've built is an innovative web browser that speeds up everyday web searches.

Work Experience

Software Engineering Consultant

2024 - PRESENT
Diffbot
  • Developed a production-ready web rendering service that seamlessly integrated with the company's SaaS platform.
  • Achieved a 2.5x reduction in latency for the new web URL rendering endpoint.
  • Implemented API features from the existing rendering service into the new service, ensuring user expectations were met through automated tests.
  • Identified and resolved minor issues and discrepancies during the gradual production rollout, minimizing impact on end-user experience.
  • Increased customer satisfaction by significantly speeding up web crawling jobs.
  • Optimized server hardware utilization, resulting in cost savings.
Technologies: Node.js, Express.js, Chrome DevTools Protocol, Chromium, Web Scraping, Playwright, Apache JMeter, Python

Lead Chromium Developer

2021 - PRESENT
Skyrocket Tech Inc
  • Set up a framework for managing a Chromium-based browser, swiftly updating to the newest Chromium version (Chromium rebasing).
  • Added automation scripts for building, testing, and deploying the Chromium-based browser. Set up GitHub Actions for continuous integration.
  • Set up automated updates using an update server and multiple application version channels (dev and production for Windows and macOS).
  • Rebranded Chromium: replaced strings, links, and any image resources containing branding.
  • Implemented numerous UI/UX improvements and additions using a mix of native and WebUI components.
  • Managed tasks in Jira. Grouped tasks into epics for different domains and phases of development. Crafted stories based on client and team input and planned specific tasks.
  • Implemented improvements around web content loading and lifecycle.
  • Relied on the Agile methodology with frequent communication, progress presentations, and short release cycles. Conducted weekly meetings to present work progress.
Technologies: C++, Chromium, Python, JavaScript, TypeScript, Amazon Web Services (AWS), MacOS, Windows, Objective-C++, GitHub Actions, React, Node.js, Electron, Architecture, Startups, Software Project Management, APIs, ChatGPT, Proof of Concept (POC), OpenAI GPT-4 API, Chrome Extensions, Full-stack, Technical Leadership, Solution Architecture, Artificial Intelligence (AI), Agile Software Development, Continuous Integration (CI), Software Design, HTTP, Software Architecture, Full-stack Development

Software Engineer

2020 - 2021
Goldman Sachs
  • Designed and implemented a new scalable version of a REST service for market data access auditing and permissioning, which improved throughput by over 500%.
  • Implemented a full CI/CD pipeline on GitLab. Implemented unit tests with 91% coverage, separated integration and system tests, and introduced fully automated deployment with Kubernetes and Docker integration to the development environment.
  • Wrote Docker files to build container images and implemented multi-environment Kubernetes deployment configurations.
  • Improved service monitoring with the addition of white-box metrics using Prometheus.
Technologies: Java 11, Java, Kubernetes, Docker, GitLab CI/CD, GitLab, Apache JMeter, JVM, Back-end, REST APIs, Banking & Finance, Architecture, APIs, Agile Software Development, API Integration, Continuous Integration (CI), Software Design, HTTP, Software Architecture, OWASP

Lead Software Engineer

2020 - 2020
Beestripe, LLC.
  • Customized the Chromium browser to provide a unique internet browsing experience under a new brand called Bright Browser.
  • Integrated an auto-update software with Chromium to provide seamless software updates for Windows and Mac.
  • Customized the Omaha client, an auto-update software for Windows. I also developed an installer for Bright Browser.
  • Integrated the Sparkle project, an auto-update component for macOS.
  • Designed and led the implementation of the Chromium upgrade process to stay up-to-date with the most recent Chromium-stable version.
  • Set up and optimized the Bright Browser build and deployment process from the technical side.
  • Integrated the Omaha server written in Django with client-side auto-update components.
Technologies: Django, HTML, CSS, JavaScript, Bash, Git, Python, C++, Chromium, Architecture, Startups, Software Project Management, APIs, Proof of Concept (POC), Full-stack, Technical Leadership, Agile Software Development, Continuous Integration (CI), Software Design, HTTP, Software Architecture, Full-stack Development, Windows

Back-end Developer

2018 - 2020
Goldman Sachs
  • Designed and implemented an authentication system.
  • Designed and implemented user management and user settings microservices.
  • Supported the platform for the pricing and trading of structured financial products.
  • Implemented REST API for brokerage firms to provide information about offered structured products.
  • Supported software development by doing code reviews, maintaining continuous integration, and a local deployment profile.
  • Oversaw deployment configuration and setup using in-house and cloud technologies. Performed production releases.
  • Implemented Kafka Streams applications to combine, enrich, and process financial data in real time with low latency and high throughput.
  • Supported the implementation of a rewards program on back-end side.
Technologies: JSON Web Tokens (JWT), OAuth, Spring, Jersey, Vert.x, Apache Kafka, MongoDB, GraphQL, REST, Microservices, Java 8, Back-end, REST APIs, Banking & Finance, GitLab CI/CD, GitLab, Architecture, APIs, Agile Software Development, API Integration, Solution Architecture, Continuous Integration (CI), Software Design, HTTP, Software Architecture, Data Engineering, Financial Markets, OWASP

Software Engineer

2015 - 2017
Vewd (Formerly Opera TV)
  • Supported the integration of an embedded Linux platform for Smart TVs.
  • Assisted with the SDK for Smart TVs, which provided HTML5 rendering.
  • Oversaw the SDK integration with an OpenGL back end on specific Smart TV platforms and models.
  • Debugged obfuscated JavaScript code of Smart TV apps.
  • Designed and implemented SDK integration tests in Python.
  • Implemented specific SDK functions as per client needs.
  • Participated in the recruitment process as the technical interviewer.
Technologies: Python, JavaScript, CSS, HTML, Streaming, Chromium, Linux, C++, C, APIs, Full-stack, Embedded Systems, Software Design, HTTP, Software Architecture, Embedded C, Embedded C++

Software Engineer | Computer Vision Specialist

2014 - 2017
DevPeer
  • Researched and improved a line segment detection algorithm in C++ using OpenCV core (client: http://www.geomagical.com/).
  • Designed and implemented a simple image search engine in Python using OpenCV.
  • Developed photo background removal tool in Python using OpenCV.
  • Created relative 360 camera pose estimation algorithm for virtual tours application (client: http://www.vizlifes.com/) using C++ and RANSAC algorithm.
Technologies: .NET, Robot Operating System (ROS), OpenCV, Python, C++, Startups, Software Project Management, APIs, Proof of Concept (POC), Software Design, Software Architecture

Junior Software Engineer

2012 - 2015
Samsung Electronics
  • Participated in developing voice UI control middleware for the Tizen mobile platform.
  • Assisted in the development of a web browser for Tizen Smart TV. Implemented logic for managing multiple tabs and Native UI elements, to name a few.
  • Participated in implementing software development processes and process requirements.
  • Created and presented project and patent proposals to the client.
  • Conducted technical training on Enlightenment Foundation libraries.
Technologies: C++, C, Linux, Embedded Systems, Software Design, HTTP, Software Architecture, Embedded C, Embedded C++, TCP/IP

Experience

GSMarkets

https://drive.google.com/file/d/1h-Raanj5lyzu12CiwpdKyRDEVu9h1ZV9/view?usp=sharing
This is a marketing platform for structured financial products (gsmarkets.de).

My responsibilities included supporting the design and implementation of the microservices platform and building authentication and user management microservices, which enabled user experience personalization.

I helped build assets and prices streaming microservices to process and deliver hundreds of thousands of financial data messages within seconds. I have supported the implementation of the monitoring system (metrics, request tracing), which helps find anomalies and bugs quickly and improve performance.

I also supported the deployment configuration, which included packaging, package delivery, deployment scripts, network configuration, scaling, and database sharding.

Automated Trading Solutions

Personal development project around (semi)automated trading:
• backtester in C++
• trading bot in C++
• real-time data collector in C++
• ETL jobs in Python
• data analysis and visualization in Python
• scripts for managing "data lake" in S3

Image Annotation Tool

https://drive.google.com/file/d/15MQQAF0x2ANpe2ay7X68ezSslBd8iavm/view?usp=sharing
I implemented an image annotation tool for Windows from scratch. It was a Windows desktop application whose primary purpose was to facilitate the creation of a training dataset for supervised learning algorithms (such as neural networks). Technologies used: .NET framework, managed C++, and MVC pattern. Views and flows were implemented according to the UI and UX designs.

Design and Implementation of an Extraction Process

Publication:
While working on the project, I contributed to OpenCV and fixed the MOG2 algorithm implementation. The extraction process involved moving objects in videos.

Posłuszny, Tomasz, and Barbara Putz. "An Improved Extraction Process of Moving Objects' Silhouettes in Video Sequences." Advanced Mechatronics Solutions. Springer International Publishing, 2016. 57-65.
(See list of contributors here: https://opencv.org/opencv-3-0/)

Bright Browser

Led the development of a Chromium-based internet browser. Integrated an auto-update feature for both Windows and Mac using open-source projects.
https://github.com/google/omaha
https://github.com/omaha-consulting/omaha-server
https://sparkle-project.org/

I designed and implemented a process for syncing with upstream Chromium major releases. I also developed and documented build and release processes. I implemented minor browser customizations and features.

RocksDB Development (on Behalf of Evolved Binary, Ltd.)

https://github.com/facebook/rocksdb/commits/master?author=alucarded
An extended RocksDB Java API (RocksJava) related to options.
I added event listeners to RocksJava, which allows better monitoring and control of RocksDB internal operations. I also implemented multiple JNI benchmarks to optimize getting DB values via RocksJava, founding some approaches to be faster in certain scenarios.

Education

2009 - 2015

Master's Degree in Robotics

Warsaw University of Technology - Warsaw, Poland

Certifications

AUGUST 2023 - PRESENT

AWS Cloud Quest: Machine Learning

Amazon Web Services Training and Certification

MAY 2023 - PRESENT

AWS Cloud Quest: Solutions Architect

Amazon Web Services Training and Certification

JANUARY 2021 - PRESENT

Microservices Foundation

LinkedIn Learning

JUNE 2020 - JUNE 2023

AWS Certified Solutions Architect – Associate

Amazon Web Services (AWS)

APRIL 2015 - PRESENT

PRINCE2® Foundation Certificate

PeopleCert

Skills

Libraries/APIs

REST APIs, Pandas, JAX-RS, NumPy, OpenCV, React, Node.js, Interactive Brokers API, Scikit-learn, Visual Studio SDK, Playwright

Tools

IntelliJ IDEA, Apache Maven, Git, GitLab CI/CD, Kafka Streams, CMake, GitLab, Apache JMeter, ChatGPT, AWS Glue, Amazon Elastic MapReduce (EMR), Amazon Elastic Block Store (EBS), Amazon Elastic Container Registry (ECR), AWS ELB, AWS IAM, AWS Key Management Service (KMS), Amazon Simple Queue Service (SQS), Amazon Simple Email Service (SES), AWS Fargate, Amazon CloudWatch, AWS CloudTrail, Amazon Elastic Container Service (ECS), Makefile, Subversion (SVN), Microsoft Visual Studio, JSX

Languages

Java, Java 8, C++, JavaScript, Python, HTML, Bash, HTML5, CSS, C, Python 3, C++17, Embedded C, Embedded C++, GraphQL, SQL, XML, Java 11, C++11, Python 2, TypeScript

Paradigms

REST, Unit Testing, Continuous Integration (CI), Microservices, Object-oriented Programming (OOP), Scalable Application, Agile Software Development, Test-driven Development (TDD), MVC Design, E2E Testing, Waterfall Development, ETL

Platforms

Linux, Amazon Web Services (AWS), Apache Kafka, Docker, Windows, Amazon EC2, Kubernetes, JVM, Visual Studio Code (VS Code), Android, Tizen, AWS Lambda, Windows UI, MacOS

Storage

MongoDB, Spring Data MongoDB, Elasticsearch, NoSQL, Amazon S3 (AWS S3), Amazon EFS

Frameworks

Spring Boot, JUnit, Django, Spring, Jersey, OAuth 2, Google Test, Redux, Boost, JSON Web Tokens (JWT), .NET, JNI, JMH, Vert.x, Windows PowerShell, Electron, Express.js

Industry Expertise

Banking & Finance

Other

Chromium, APIs, Back-end, Proof of Concept (POC), Full-stack Development, HTTP, Full-stack, Software Architecture, Software Design, Technical Leadership, Data Engineering, Computer Vision, Machine Learning, Minimum Viable Product (MVP), Architecture, Startups, Software Project Management, Chrome Extensions, Embedded Systems, Solution Architecture, Artificial Intelligence (AI), API Integration, Financial Markets, Amazon API Gateway, Amazon Kinesis, Streaming, Video Streaming, Leadership, Shell Scripting, OAuth, OANDA API, Big Data, Robot Operating System (ROS), Algorithms, Objective-C++, GitHub Actions, OpenAI GPT-4 API, Prompt Engineering, Trading, TCP/IP, OWASP, Chrome DevTools Protocol, Web Scraping

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