Filip Defar, Developer in Zagreb, Croatia
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Filip Defar

Verified Expert  in Engineering

Data Visualization Developer

Zagreb, Croatia

Toptal member since May 12, 2014

Expertise
Data VisualizationGitCSSJavaScriptRubyRuby on RailsReact.jsD3.jsAgile DevelopmentjQueryPostgreSQLTypeScriptVue.jsPython
Bio

Filip is a full-stack web developer with a special interest in data visualization. He has several years of professional experience working remotely on large-scale applications and building MVPs. Filip has built data visualization dashboards used by the government of Saudi Arabia, refactored and saved de-railed web applications, and helped with developing the Toptal platform you are currently using.

Portfolio

Captario AB
React, D3.js, Python, TypeScript, Visx, Pandas, Data Visualization...
Samedi
HTML, CSS, JavaScript, TypeScript, Ruby, Ruby on Rails (RoR)...
African Budget Safaris
JavaScript, Vue, HTML, CSS, Webpack, User Interface (UI)

Experience

  • JavaScript - 8 years
  • CSS - 8 years
  • React - 3 years
  • PostgreSQL - 3 years
  • Data Visualization - 3 years
  • D3.js - 3 years
  • TypeScript - 2 years
  • Python - 1 year

Availability

Part-time

Preferred Environment

Git, Visual Studio Code (VS Code), Linux, Windows Subsystem for Linux (WSL)

The most amazing...

...work experience I've had was helping build Toptal's talent platform in collaboration with a team of over 100 remote developers.

Work Experience

Front-end Developer

2021 - 2022
Captario AB
  • Consulted with the client on best practices regarding developing interactive data visualizations with D3.js and React.
  • Refactored existing front-end data visualization code and added new features, such as "brush and zoom," to existing visualizations.
  • Built new data visualizations, working across full-stack, and developing custom interactive front-end within React ecosystem. Prepared and cleaned large datasets on the back end with Python and pandas.
  • Worked with the design team on maintaining and developing the UI surrounding the data visualization dashboards.
Technologies: React, D3.js, Python, TypeScript, Visx, Pandas, Data Visualization, User Interface (UI), Redux, Unit Testing, Jest

Full-stack Developer

2018 - 2021
Samedi
  • Led the technical side of a web portal redesign, ensuring CSS/HTML code follows best practices.
  • Gave feedback on designs and helped improve technical UI issues as well as UX issues.
  • Spearheaded the integration of PayPal payments API into an existing React application with a Ruby on Rails back end.
  • Reworked an existing React application to use SEO-friendly URLs.
  • Worked on fixing cross-client rendering issues in HTML email templates.
Technologies: HTML, CSS, JavaScript, TypeScript, Ruby, Ruby on Rails (RoR), User Interface (UI), React, Responsive UI, Redux, Unit Testing, Jest

UI Developer

2019 - 2020
African Budget Safaris
  • Built a web application for searching and dynamic filtering of safari tours. This application is the core of the new (unreleased) website. It uses the Vue.js framework for the front end and communicates with Google Cloud Functions API.
  • Created a simple webpack configuration to use modern JavaScript while retaining compatibility with legacy browsers.
  • Worked with the client on fixing various layout (CSS/HTML) issues across the new website.
Technologies: JavaScript, Vue, HTML, CSS, Webpack, User Interface (UI)

Front-end Developer

2018 - 2019
AlignAlytics
  • Implemented a customizable SVG-based multi-column visualization for comparing data in various forms, including text, lists, bar charts, and heat maps.
  • Created a value chain visualization for a client company.
  • Built a CLI for synchronizing code between the local development environment and the Alytic.io web service.
  • Developed a generic radar chart template to be used as part of the Alytic.io platform.
  • Designed and created a custom chart showing relationships between three datasets.
  • Created several variations of interactive tree chart visualizations.
Technologies: D3.js, CSS, JavaScript, Git, Data Visualization, HTML, Affinity Designer, User Interface (UI)

Front-end Developer

2017 - 2018
Wasphi
  • Created a set of reusable React and D3.js visualization components for basic charts.
  • Built several custom non-standard chart components with D3.js.
  • Helped design and build a dashboard allowing data exploration of Saudi workers abroad.
  • Designed and built a dashboard that allows the data exploration of average student grades in various educational institutions.
  • Created a dashboard showing Saudi labor market trends.
Technologies: TypeScript, React, D3.js, CSS, JavaScript, Git, Data Visualization, HTML, Affinity Designer, User Interface (UI), Dashboards

Front-end Developer

2017 - 2017
Dekunu Technologies
  • Built an interactive visualization dashboard with positional data collected from skydivers during jumps.
  • Developed an algorithm to clean up spotty GPS data.
  • Developed an algorithm for detecting moments when the skydiver exited the plane, opened the parachute, and landed.
Technologies: D3.js, JavaScript, CSS, Git, Data Visualization, HTML, Affinity Designer, User Interface (UI)

Ruby Developer

2016 - 2017
Toptal
  • Worked in a team of over 100 developers on maintaining the very platform you are using right now.
  • Led the development of the Top Scheduler application used for scheduling meetings with Toptal clients.
  • Continuously worked with PMs on directing the product and making sure code deliveries are made on time.
  • Acted as an Agile coach for our team, making sure our Kanban-based process is running smoothly.
Technologies: Ruby on Rails (RoR), Ruby, CSS, Test-driven Development (TDD), PostgreSQL, Agile Software Development, Git, HTML, Object-oriented Programming (OOP), Object-oriented Design (OOD)

Back-end Ruby Developer

2015 - 2015
DirectVest (via Toptal)
  • Created an API wrapper for a folio institutional service.
  • Constructed a full test suite for existing features.
  • Refactored the application (From 1.5 to 3.9+ GPA on CodeClimate).
  • Implemented multistep forms for the investment process.
  • Built a dashboard that heavily relies on external APIs as well as low-level caching for increased performance.
Technologies: Ruby on Rails (RoR), CSS, Ruby, Test-driven Development (TDD), PostgreSQL, Git, HTML, Object-oriented Programming (OOP), Object-oriented Design (OOD)

Full-stack Ruby/JavaScript Developer

2015 - 2015
BizRevr (via Toptal)
  • Helped design and develop new features.
  • Created an interface for bulk editing records similar to an Excel spreadsheet.
Technologies: jQuery, JavaScript, Ruby on Rails (RoR), CSS, Ruby, Test-driven Development (TDD), PostgreSQL, Git, HTML, Object-oriented Programming (OOP), Object-oriented Design (OOD), User Interface (UI)

Full-stack Ruby/JavaScript Developer

2014 - 2015
ThinkCERCA (via Toptal)
  • Created a one-page JavaScript application for assigning lessons to students.
  • Maintained, improved, and added new features to existing Ruby on Rails and Ember.js code.
Technologies: CoffeeScript, PostgreSQL, Ember.js, Ruby on Rails (RoR), CSS, JavaScript, Ruby, Test-driven Development (TDD), Agile Software Development, Git, HTML, Object-oriented Programming (OOP), Object-oriented Design (OOD), User Interface (UI)

Back-end Ruby Developer

2013 - 2014
CampWire
  • Created a working payments system.
  • Improved old core features and created new ones.
  • Introduced new developers to the application.
  • Wrote a full test suite for the application.
Technologies: Heroku, PostgreSQL, jQuery, Ruby on Rails (RoR), CSS, Ruby, Test-driven Development (TDD), Git, HTML, Object-oriented Programming (OOP), Object-oriented Design (OOD)

Back-end Ruby Developer

2012 - 2013
Whitespectre
  • Developed a web service for creating mobile application presentations.
  • Created a web application test suite using RSpec.
Technologies: PostgreSQL, Ruby on Rails (RoR), CSS, Ruby, Test-driven Development (TDD), Git, HTML, Object-oriented Programming (OOP), Object-oriented Design (OOD), jQuery

Experience

My Codepen Account

https://codepen.io/dabrorius
I am an active member of the CodePen community, building CSS and JavaScript examples in my free time. This includes everything from data visualizations, SVG experiments, animated UI components to an occasional visual art project.

Rotten Unicorns Website

Rotten Unicorns is a local band collective for which I designed, built and deployed a responsive website.

I used Sketch for prototyping and Affinity Designer for logo design. The website was built with HTML5, SCSS, and Webpack and deployed to GitHub Pages.

My Blog

http://filipdefar.com/
This is my blog where I write about technologies that currently interest me as well as my thoughts and experiences as a remote developer.

Education

2011 - 2013

Master's Degree in Computer Science

University of Zagreb - Zagreb, Croatia

2007 - 2011

Bachelor's Degree in Software Design

University of Zagreb - Zagreb, Croatia

Skills

Libraries/APIs

React, D3.js, jQuery, Vue, Liquid, Pandas, Three.js, Node.js

Tools

Git, Webpack, Affinity Designer

Languages

HTML, CSS, JavaScript, Ruby, TypeScript, Python, CoffeeScript

Frameworks

Ruby on Rails (RoR), Ember.js, Redux, Jest

Paradigms

Object-oriented Programming (OOP), Test-driven Development (TDD), Agile Software Development, Object-oriented Design (OOD), Unit Testing

Platforms

Visual Studio Code (VS Code), Heroku, Linux, Shopify

Storage

PostgreSQL

Other

Data Visualization, User Interface (UI), Visx, Windows Subsystem for Linux (WSL), Computer Science, Software Design, Shopify Theme, Responsive UI, Dashboards

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