Maciej Karaś

Senior Software Engineer at MongoDB

Warsaw, Mazowieckie, Poland

About

As a Software Engineer with over 15 years of experience, I've witnessed firsthand how rapidly technology evolves. My journey has taken me from building Java Enterprise applications with EJBs and SOAP interfaces, through the era of Kotlin and Spring Boot development and Android applications, to today's lightning-fast GO applications deployed in the cloud and on Kubernetes clusters. While the tech stack has transformed dramatically, my core philosophy remains unchanged: putting customers first and focusing on product experience. I'm a technology enthusiast who thrives on learning—whether it's new frameworks, tools, programming languages, or innovative approaches to problem-solving. But here's what experience has taught me: users don't care about the elegance of your clean architecture or the novelty of your tech stack. They care about whether your solution solves their problems effectively and efficiently. This perspective is what I consider my greatest strength: the ability to match the right technology to real user needs, drawing from over a decade and a half of hands-on experience across diverse platforms and architectures.

Experience

  • Senior Software Engineer at MongoDB
    Aug 2024 - Present · 1 yr 11 mos

  • Form3 (Warsaw, Mazowieckie, Poland · Remote)
    • Technical Lead
      May 2023 - Jul 2024 · 1 yr 3 mos

      Technical Lead for Events Team. Helping team maintain and develop micro-services and libraries used in Form3 platform. Working with high volume of transactions demands lot of attention to performance and stability. Supervising cost reduction initiatives for services and databases used in the team. Working on daily bases with product team and making sure the team work is aligned with what is needed. Organising work for the team and being a mentor and a helping hand.

    • Senior Software Engineer
      May 2022 - May 2023 · 1 yr 1 mo

      Senior Software Engineer in Auth and Events teams. Maintaining and developing micro- services and libraries used in Form3 platform. Biggest project so far was migrating services to the Cloud Agnostic platform. Worked in teams focused on platform authorization, events messaging and contracts, audit and billing. Most applications written in Go/Java, run in K8s multi-cloud stacks.

  • Senior Software Engineer at Operator Chmury Krajowej
    Jan 2020 - May 2022 · 2 yrs 5 mos

    Senior Software Engineer mainly focused on backend services deployed on Google Cloud Platform. Responsible for architecting and developing backend components in major projects: - e-Wizyta - online doctor consultation platform based on Google Meet videoconference engine, deployed to resolve need for medical assistance during Pandemic - e-Rejestracja - national COVID-19 vaccine registration system Other projects include infrastructural project in Terraform/Terragrunt for GCP, applications mainly written in GO and deployed on GCP and many devops assignments.

  • Senior Software Engineer at KMD Poland
    Apr 2019 - Dec 2019 · 9 mos

    Tech lead and Scrum Master for STS Java Team. Taking care of development process continuously improving it. Responsible for overall quality of code and releasing it successfully to production, maintaining it and making sure it meets desired SLA's. Mentoring, facilitating knowledge sharing and communication inside team.

  • Braintri (Warsaw, Masovian District, Poland · On-site)
    • Software Architect
      Sep 2017 - Apr 2019 · 1 yr 8 mos

      Responsible for delivery of backend/mobile solutions in Banking/Insurance sector from start to finish (gathering business requirements, designing application architecture, project management and development). Required proficiency in JVM languages, enterprise frameworks (JEE, Spring etc) and architectural solutions.

    • Android and Java Software Developer
      Apr 2015 - Sep 2017 · 2 yrs 6 mos

      Mainly Android Developer, but also involved in other developments, such as: Java EE backend for mobile applications; Hadoop solutions with Flume and Scala applications based on AWS architecture. Biggest project by far has been Android application for a leading universal bank.