Jacek Szarski

Full stack Elixir / Ruby engineer

About me

I am a full-stack programmer passionate about web development.
I’ve been working with Ruby and JavaScript continuously since 2007 and Elixir since 2018.

I believe technical knowledge is only a part of the equation. Communication, planning, persistence, proactiveness, thoughtfulness and passion take equally big part of being a great programmer. I believe people with the right attitude are the most important part of any company. I value quality, innovation, being practical and serious about what we do and having fun at the same time. I want to work with people that think alike.

I am based in Krakow, Poland. I’m looking for remote jobs, but I’m open to traveling when needed.

What I use

Languages: Ruby, Elixir, JavaScript (&CoffeeScript)

Ruby frameworks: Ruby On Rails, Padrino, Sinatra

JavaScript libraries: React.js, Backbone.js, handlebars, Knockout, Underscore.js, jQuery

Testing: RSpec, Behavior Driven Development, (/Test Driven Development)

Hosting: AWS (ec2, s3, Route53), Heroku, custom solutions

Communication: standups, iteration planning, ticketing system, pull requests (code reviews), group chat and pair programming

Versioning: proficient in Git

Experience with: building APIs, integrating with APIs, pure JavaScript applications, JavaScript UI, Service Oriented Architecture, continuous integration, silent releases, databases, configuration management (Chef), containerization and virtualization (Vagrant, VirtualBox, VmWare etc), social media integration

Other standards: OpenAPI, HTTP, REST, CRUD, HTML, CSS, SASS, JSON, XML, AJAX, OAuth, markup languages

Soft skills: problem solving, organizing work, implementing and improving processes, fast learning

Not just slogans to me: Extreme Ownership, “Be the master of your domain”, “Work smarter, not harder”, “If you can’t measure it, you can’t manage it”, “Work with small tasks only”, “Leave your ego at the door”, “Be conservative about your work and liberal about the work of others”


[REMOTE] FULL STACK SOFTWARE ENGINEER @ UpHex (uphex.com) / Patient Stream (mypatientstream.com)

July 2017 - June 2021

UpHex is a small, full-remote startup originating in Charlottesville, Virginia. patientstream.com is an advanced system for automating Facebook campaign creation, that uses algorythms to optimize ads for maximum results. uphex.com analyzes marketing campaign data to give its users better insight into their online ad spend.

  • building and maintaining an Elixir application for high-throughput data fetching from Facebook Ads and Google Adwords APIs
  • working very closely with Facebook Marketing API to create campaign creation and optimization algorythms in Elixir
  • designing and maintaining an architecure of microservices (Rails and Elixir) connected via internal APIs
  • building beautiful UI in React.js and Padrino (Ruby)


November 2015 - February 2017

Stack Builders is a distributed-first software house based in Quito, Ecuador, with skilled developers working from all around the world. I was working on two customer projects:

ROR DEVELOPER FOR HAYSTAK (now www.dealer.com)

November 2016 - February 2017

  • building a high-performance integration with Google Adwords and Bing Ads

ROR DEVELOPER FOR DURST (portal.durst.org, via57west.com, helena57west.com and other)

November 2015 - November 2016

  • building a real-estate platform for improving the leasing business
  • integrating with external leasing services


  • participating in creating company’s long-term policies regarding communication, growth and quality

RAILS SOFTWARE ENGINEER @ BASE CRM (now Zendesk Sell, zendesk.com/sell)

April 2013 - October 2015

Base CRM was a startup based in Krakow, Mountain View and San Francisco. Its goal was to make sales teams 10x more productive by betting on new technology and innovative solutions. Later acquired by Zendesk.

  • tearing off layers of a monolith Rails app and rebuilding as microservices in a large SOA infrastructure
  • building multiple external integrations, interactive tour system for users and many other components
  • maintaining quality and reliability of microservices responsible for the key features of the system
  • building and maintaining a pure-javascript frontend application
  • helping newcomers get up to full speed


October 2007 - April 2013

Applicake was a Krakow-based software house building web services mostly for clients from U.S., England, Canada and Germany. Some of my most interesting roles:


October 2012 - April 2013

As GPM my responsibility was leading the Dev Team of about 25 people spread across 5-8 client-facing teams. My daily duties included:

  • building customer relationships and teaching our process to them
  • establishing development scope, team members, rates, agreement type, deadlines, release milestones
  • managing schedules for all project teams: assigning to teams, managing company availability
  • mentoring teams on keeping the right focus, aligning vision with the client, implementing agile practices, estimating new features, maintaining development roadmap, release planning and maintaining code quality


May 2012 - October 2012

  • researching and integrating best technologies to implement an innovative one-page video streaming platform
  • developing a flexible application to allow for quick pivots and testing multiple strategies


December 2010 - January 2012

  • coordinating work of five internal developers, dev-ops and client’s remote team (designers, back end developer, wordpress developers)
  • developing a matching mechanism for online dating - joining flexibility, performance and 100% reliability
  • maintaining very quick feature release paste by enforcing high visibility within the team
  • recruiting client’s US-based team members
  • coordinating project hand off to an external company


November 2008 - November 2010

  • laying the groundwork for the service and implementing primary features
  • integrating with PayPal payments system


Master of Science, Electronics & Telecommunications 2005 - 2012
@ AGH University Of Science And Technology, Krakow, Poland

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