Filip Mamcarczyk

Software Engineer

Cracow, Poland10 yrs 11 mos experience
Most Likely To Switch

Key Highlights

  • Over 10 years of frontend development experience.
  • Led migration of legacy codebases to modern frameworks.
  • Contributed to products used by millions globally.
Stackforce AI infers this person is a SaaS and Fintech expert with strong frontend development skills.

Contact

Skills

Core Skills

React.jsJavascriptTypescriptAngularApplication ArchitectureUser InteractionOptimization

Other Skills

PlaywritingRedux.jszustandRepresentational State Transfer (REST)Front-End DevelopmentProduct RequirementsProduct DevelopmentWeb Application DevelopmentRxJSSoftware as a Service (SaaS)jQueryGitPhotoshopAmazon Web Services (AWS)SASS

About

Making Frontend parts of successful products (Hotjar, Codewise) shiny and neat for over 10 years now. Life's too short to keep cool things locally on the branch, let's be pragmatic - done is better than perfect!

Experience

10 yrs 11 mos
Total Experience
2 yrs 4 mos
Average Tenure
5 yrs 9 mos
Current Experience

Kit

Senior Software Engineer

Jan 2026Present · 4 mos · Remote

Doist

Frontend Engineer

Jun 2025Jan 2026 · 7 mos · Remote

  • contributing to and improving the frontend layer of the Todoist App, used by over 30 million people around the world
  • proposed and implemented the automated flow for maintaining the feature flags in the frontend app
  • contributed to async-first collaboration culture through clear documentation, RFCs, and thoughtful code reviews
React.jsJavaScriptPlaywritingRedux.jszustandTypeScript

Focal systems

Senior Frontend Developer

May 2024Jun 2025 · 1 yr 1 mo · Remote

  • extended the frontend layer of the FocalOS app used to manage almost 2k stores
  • boosted the app performance by detecting the bottlenecks and addressing them with fixes and improvements to the rendering and fetching logic
  • led the cross-team process of migrating the old legacy codebase (React 17, Redux Saga, Thunks, Ramda) to modern solutions in the other parts of the app (React 18, RTK Query)
  • developed the e2e testing framework in Playwright and set up the automated sanity checks in GitHub actions that saved 2 hours of daily manual testing by the QA engineers
Representational State Transfer (REST)React.jsApplication ArchitectureJavaScriptUser InteractionFront-End Development+3

Hotjar

Software Engineer, Frontend

May 2022May 2024 · 2 yrs

  • developing the frontend layer of Hotjar’s core product, session recording tool
  • developing the frontend features used horizontally across different Hotjar’s products
  • taking part in cross-squad initiatives focused on a11y and observability
Representational State Transfer (REST)TypeScriptReact.jsProduct DevelopmentApplication ArchitectureUser Interaction+3

Backbase

Senior Frontend Developer

Jun 2021May 2022 · 11 mos · Cracow, Małopolskie, Poland

  • developing frontend layer of a Backbase banking platform (with a focus on batch payments used by US banks)
  • taking part in the process of creating new prodcut team from scratch (establishing process and workflows)
  • cooperating with FE devs from different teams to provide improvements for the FE guild
Representational State Transfer (REST)Web Application DevelopmentTypeScriptAngularApplication ArchitectureJavaScript+4

Jak zacząć programować?

Creator

Aug 2020Present · 5 yrs 9 mos

  • https://www.youtube.com/channel/UCF4jzVCa2J45NXnNtf6XBoA?sub_confirmation=1
  • "Jak zacząć programować?" powstało z myślą o osobach, które chcą postawić swoje pierwsze kroki w kodzeniu lub dowiedzieć się więcej o pracy programisty i branży IT. W materiałach, które tworzymy przekazujemy wiedzę i porady, które sami chcielibyśmy usłyszeć na starcie naszej przygody z programowaniem.

Codewise.com

Senior Frontend Developer

Jul 2016Jun 2021 · 4 yrs 11 mos · Kraków, Mazowieckie, Poland

  • Developing Frontend layer of Voluum - cloud-hosted tracking software that provides data analytics insights and AI-powered optimization tools to make advertising easier and more profitable.
  • Technologies used:
  • Angular, RxJS, Typescript, Less, Jasmine, Protractor, AWS, Jade, Jenkins, Circle CI
  • Main responsibilities:
  • developing frontend layer of Voluum (https://demo.voluum.com/)
  • creation of components library used in Voluum project
  • taking part in the recruitment process - preparing exercises, reviewing CVs and taking part in job interviews
  • writing unit and e2e tests
  • mentoring interns and junior devs that joined the team
  • sharing knowledge among the team during frontend tech talks
Representational State Transfer (REST)Application ArchitectureUser InteractionOptimizationProduct Requirements

Vml poland

2 roles

Front-End Developer

Feb 2016Jun 2016 · 4 mos · Kraków, Mazowieckie, Poland

  • Developing frontend layer of Brand Fibres Project (social media analysis system): user panel customization, creation of new widgets (charts, word clouds, etc.), refactoring old modules (both .css and .js)
  • Technologies used: HTML, SCSS, JS, jQuery, Backbone.js
Representational State Transfer (REST)User InteractionOptimizationProduct Requirements

Junior Front-End Developer

Apr 2015Jan 2016 · 9 mos · Kraków, Mazowieckie, Poland

  • Creating frontend layer of big advertising campaigns for major brands (Lays, PZU, Orange and others).
  • Technologies used: HTML, CSS, SCSS, JS, jQuery
Optimization

Education

Cracow University of Technology

Inżynier (Inż.)

Jan 2012Jan 2015

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