Pavel Puzikov, Data Visualization Developer in Amsterdam, Netherlands
Pavel Puzikov

Data Visualization Developer in Amsterdam, Netherlands

Member since October 2, 2014
Pavel was a founding CTO in a startup sold at $17m evaluation, built largest data science competition platform in Africa and has work featured on Working since 2008, he mostly enjoys working on new things in small teams. Passionate about speed, humane interfaces and data visualisation.
Pavel is now available for hire




Amsterdam, Netherlands



Preferred Environment

OS X, Vim, Tmux

The most amazing...

...thing I've built is, the largest data science competition site in Africa


  • Full Stack

    2018 - PRESENT
    • I'm the sole developer of an internal platform for a data analysis company with an academic background which provides consultations for city and country management on when and which water pipes to replace.
    • I inherited a rather antiquated codebase and rewrote most of it making everything fast and stable at last.
    • Especially proud of the new statistic calculations and visualization module.
    Technologies: Ruby on Rails, React, D3.js, MySQL
  • Data Visualization

    2020 - 2020
    • Built a front-end for a COVID-19 graph exploration tool.
    • Tried and tuned several graph layout algorithms, providing natural, timeline and map-oriented views.
    • The tool provides exploring node relatives and finding the shortest path to other nodes in a clean interface with google maps-like panning and zooming.
    Technologies: React, D3.js, Docker
  • Full Stack

    2018 - 2020
    • Zindi is the largest data science competition site in Africa.
    • I worked with founders from the start to figure out what it is we're creating, then architected and built the tech.
    • I built Ruby on Rails API backend, deployed into an auto-scaling pool in the cloud.
    • And React frontend. There are rendering servers and a CDN static version it falls back to when under heavy load. It makes it almost impossible to break or take down.
    • Zindi hit 10k competing data scientists early 2020 and has Microsoft, Uber and Amazon as partners.
    Technologies: React, Flowtype, Ruby on Rails, PostgreSQL, Docker, AWS, Azure
  • Developer

    2016 - 2017
    • Co-founded a company to create an iOS messaging and notes application.
    • Our idea was to consider the user's environment to find the best moments to deliver information—e.g., send someone a note or a song to be delivered only when they're traveling, or home alone on Friday evening.
    • I handled all tech and most of UX development. Have used location, movement, weather data, etc to train prediction models and figure out particular moments; and built a series of prototypes, including Facebook Messenger bot, website, and iPhone app.
    Technologies: React, React Native, Ruby, AWS, PostgreSQL, TensorFlow
  • Full Stack

    2016 - 2016
    Votecastr | with
    • Votecastr was publicly providing real-time election results during the US 2016 election day in a way that was only available to candidates before — by using pre-trained models and live exit polls data.
    • I was responsible for designing and building all tech except mobile applications and prediction models itself.
    • API for the mobile app for people at polling places.
    • Internal tool for communicating with remote agents and the data validation.
    • Infrastructure to re-run the models as data was updated.
    • The interactive dashboard on and our website.
    Technologies: Ruby, React, PostgreSQL, D3.js, Twilio
  • Full Stack

    2015 - 2015
    Predictions Dashboard
    • Data analysis and predictions company needed a nice and secure way to display their very complex data to their client. I was given huge CSV files, updated weekly and a carte blanche in system design.
    • Querying was the first problem — I decided to go with Google Cloud Bigtable database for guaranteed latency and created a scheduled service to parse and sync new CSVs from AWS S3 into Bigtable weekly.
    • Built a Rails-based back-end with two-factor authentication for data API and user management panel.
    • Created the front-end with React and heavy use of D3.js. It was a complicated graph with customizable projections, filters, and contextual data. I just finished Edward Tufte's dataviz book at a time and was very happy to put my new knowledge at work.
    Technologies: React, D3.js, Ruby, Bigtable, PostgreSQL
  • CTO

    2012 - 2014
    • Worked with founders right from the start on the social marketing platform, building the first version as a contractor and joining them later as a CTO. It was recently sold at a $17 million valuation. I architected and built all tech, including:.
    • Client and managers cabinets for setting up and managing campaigns.
    • Customer-facing part constructors — for various landing pages, emails and pop-ups.
    • An embedded minimum impact JavaScript library for data exchange and loading widgets.
    Technologies: Ruby, MySQL, PostgreSQL, Angular, AWS, Chef
  • Web Developer

    2010 - 2013
    • Founded and ran a web consultancy.
    • Worked with a variety of clients, mostly startups on early stages. Clients included (a real estate site inspired by, (a job board inspired by, (electronic music forum), and (a video hosting and social recommendations site).
    • Aimed to be kind of an outsourced CTO, working with founders from the very beginning, making early prototypes, planning architecture, building the actual product, and then hiring and transferring a project to an in-house team.
    Technologies: Ruby on Rails, jQuery, Google Closure Library, AWS
  • Lead Developer

    2009 - 2010
    • Worked closely with founder to rebuild a project from scratch. It was the first time I was responsible for the whole project.
    Technologies: Ruby on Rails, jQuery, Google Closure Library
  • Lead Front-end Developer

    2008 - 2009
    Thematic Media
    • Joined as a front-end developer and ended up being a team lead.
    Technologies: JavaScript, HTML, CSS, jQuery, Mootools, Google Closure Library
  • Front-end Developer

    2008 - 2008
    • Developed all front-end features for this startup company.
    Technologies: JavaScript, HTML, CSS


  • Zindi Africa (Development)

    The biggest platform for hosting data science competitions in Africa. Worked very close with founders to architect and built it. Hit 10k users early 2020 and has Microsoft, Uber and Amazon as a partners. It's Ruby on Rails and React, hosted on Azure and partially on AWS.

  • Dorsia (Development)

    I was the sole and then the lead developer in the from-the-ground-up rebuild of this very good looking website. The map was real fun to work on, we experimented a lot with it. Rails API and React frontend.

  • Votecastr (Development)

    Real-time voting coverage and prediction app for US 2016 elections in partnership with Slate. I was responsible for data processing, live dashboards, and maps on our website and, admin panel, and dashboard for monitoring and curating incoming data and API to communicate with people in field—in short, for all tech except the Android app and actual prediction models.


  • Languages

    TypeScript, HTML, Ruby, JavaScript, Clojure, Elm, Python, R
  • Frameworks

    Redux, Ruby on Rails (RoR), React Native, ClojureScript
  • Libraries/APIs

    D3.js, Node.js, React
  • Tools

  • Paradigms

    Web Performance Optimization (WPO), Functional Programming
  • Platforms

    Amazon Web Services (AWS), Azure, Google Cloud Platform (GCP), Docker
  • Storage

    MySQL, PostgreSQL
  • Other

    Data Visualization, Software Engineering, Google, Google Software Engineer


  • Coursework in Computer Science
    2004 - 2008
    Saint Petersburg State University of Information Technologies, Mechanics and Optics - Saint-Petersburg, Russia


  • John Hopkins Data Science
    John Hopkins University | via Coursera
  • Bioinformatics Algorithms
    UC San Diego | via Coursera
  • Andy Ng's Machine Learning Course
    JUNE 2014 - PRESENT
    Stanford University | via Coursera

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