Hi, my name is Dan Zajdband.  I’m an Argentinian software developer currently living in Colombia. I’m passionate about real-time technologies, open source projects, Virtual Reality and Open Journalism.  I contribute to a wide diversity of open source projects including both end user software and tools for developers.  My interest in Open Journalism led me to participate and be part of the Hacks/Hackers Buenos Aires and Media Party core team.  I help building the community by encouraging colleagues to join, creating projects like HackDash and data visualizations (e.g. Real-Time geolocated tweets, Protests in Buenos Aires).  I enjoy sharing my experience and learning from others.  I co-created BAFrontend, one of the top web technology meetups in Argentina,  I’m part of the JSConf Argentina organization team, and I also write articles and give technical talks at Conferences and meetups.

My skills include both Front end and Back end software development, allowing me to build apps from scratch.  I usually work in interdisciplinary teams, especially with journalists and designers.  My experience includes collaborating in newsrooms and events.  I’m continually improving my skills by learning new tools and languages like JavaScript, Python, PHP, Go, HTML5 and WebGL.

  • Guri VR (GitHub repo): This project allows non-programmers to create VR scenes by describing what they want to see on an online text editor. The generated scenes are instantly available for sharing and works with desktop browsers, mobile devices, and headsets like the Oculus Rift and Google Cardboard.
  • HackDash (GitHub repo): I built HackDash as a tool for creating dashboards for hackathons.  It was born to be used by Hacks/Hackers Buenos Aires at the 2012’s Media Party hackathon.  A further explanation can be found on this blog post.  Ever since HackDash was born it was used by governments (both the Buenos Aires City and the Argentinean National Government official hackathons) and organizations like OpenNews and National Geographic. The usefulness of HackDash is not limited to organizing hackathons but for showcasing many different projects.  To date, +3,100 projects were created by +5,400 users around the world.  The project is under heavily development having a paid developer dedicated to it.
  • Tuiter: Tuiter is a library intended to ease the usage of the Twitter APIs for node.js developers. Since the nature of node has a lot to do with real-time applications along with the success of Socket.io makes a lot of sense to use Tuiter to build Twitter visualizations.  Using Tuiter I made a Real-time geolocated tweets visualization that has been featured in The Guardian and VentureBeat, among others.  I also made other visualizations that have had wide impact, such as this Real-time Twitter clients distribution chart.
  • Next.js: Next is a Framework for server-rendered React apps. I’m one of the framework authors and maintainers.
  • DatoCHQ: DatoCHQ is a platform aiming to broaden the chequeado.com datasets by enabling the public to share their own information.  After being reviewed by the Chequeado.com staff, the validated data is incorporated to the database used to improve the fact-checking process. I had the original idea for this project, and helped with the project management and development.  DatoCHQ was awarded and got funding from the World Bank, the ICFJ, and HacksLabs.
  • More projects with Chequeado.com: Since 2012 I’ve been working with Chequeado.com, the largest fact-checking website in Latin America. I work with them evaluating project and building tools and visualizations.  I’d like to feature two projects where I was deeply involved and that I really like.  The first one consists in a tool developed specifically to enable the real-time fact checking of Argentina’s “State of the Union” speech delivered by the President to the Congress.  Journalists and experts in different areas gather at the University of Buenos Aires Law School to check the facts included in the speech. I was involved in the development of the tool as well as in supporting the event.  The second is a learning tool that allows the public to use the same methodology applied by Chequeado in fact-checking.  This app shares the robust and proven methodology of chequeado.com with users so that they may fact check quotes on their own.
  • Balloons.IO (GitHub repo): Balloons.IO is a web multi-room chat server and client ready to use.  It’s built with the help of node.js, Express, Socket.IO and Redis.  Balloons uses PassportJS for authentication with Twitter and Facebook.  The idea behind Balloons.IO is to show the power of node.js combined with a cutting edge database like Redis and a nice UI. It got the attention of many developers and sites because it was one of the first projects showing the node.js capabilities.
  • 8n Hack (GitHub repo): There was a large political demonstration on November 8, 2012 in Buenos Aires. With the help of Hacks/Hackers Buenos Aires members, I built a set of real-time visualizations-featuring the events of the demonstration. It was covered in several media sites.
  • CartoDB node.js library: CartoDB is an excelent tool for creating map visualizations. I like their work, so I helped them rebuild the CartoDB API wrapper for node.js.
  • Instapolls (GitHub repo): Instapolls is a product I built while I was working at Vulsai. It is a real-time polling web system. The users can create polls just by adding choices and see in real-time the public answers. One of the best features is the embeddable widget, used for inserting polls into other websites. I created it with the help of a designer in two days. It was pretty fun and it was used in many ways including a TV show from Argentina’s national TV.

Personal Information


  • Engineer – Daffy (2021 – present): I’m currently working at Daffy a startup trying to make giving a habit.
  • Engineer – Accel Robotics (2019 – 2021): I worked at Accel Robotics building next-generation retail experiences using AI.
  • Back End Team Lead – Brubank (2017 – 2019): Lead and managed the Back End team behind Brubank.
  • Knight-Mozilla Fellow – Coral Project (Mozilla / New York Times / Washington Post) (2016 – 2017): Collaborating with the Coral Project Open Source projects and also experimenting with VR in Journalism.
  • Lead Front End Developer – Mango (2013 – 2015): Online payment solution for developers & businesses in Latin America.  I created and maintain the Customers control panel, wrote the JavaScript SDK and development libraries.
  • IT advisor – Chequeado (2012 – present): Argentinian fact-checking newsroom.  I work with the team creating apps and visualizations.  I help with the evaluation and implementation in all the technology-related projects.
  • Freelance Developer (2007 – 2013): Mostly web development doing Back End and Front End work.
  • Senior Developer – theLIFT (2012 – 2013): Digital innovation agency based in San Diego, CA.  I worked along with startups and large companies like Sony and Qualcomm building creative and robust web-based products and campaigns.  I developed the first version of what became the Zappos Pop-Up Shop machines and worked on many other projects for organizations like Qualcomm and the Red Cross.
  • Senior Developer – Vulsai (2011 – 2012): Digital creative studio based in Buenos Aires, Argentina.  I built applications for Disney and Univision while contributing to open source projects.
  • Co-founder – Gravity On Mars (2009 – 2011): GoM was a studio that created Open Source projects that provided solutions to the community and companies.  I co-founded the studio and built several apps like Balloons.IO.


In the media

Online Courses I taught



  • University of Buenos Aires – B.Sc. Computer Science Candidate (Relevant coursework: Statistics, Algorithms, Operating Systems, Natural Language Processing)


Programming languages

  • JavaScript
  • Go
  • PHP
  • Python
  • Erlang
  • C
  • C++
  • R
  • Web technologies (CSS, HTML)


  • MySQL
  • PostgreSQL
  • Redis
  • MongoDB
  • ElasticSearch

Social Media