Antonin is available for hire
Hire AntoninAntonin Januska
Verified Expert in Engineering
Software Developer
Boulder, CO, United States
Toptal member since April 8, 2020
Bio
Antonin is a versatile full-stack developer with a strong JavaScript background. He has built entire products from scratch in Node.js, React, Angular, and other popular JavaScript technologies. He also comes from a PHP background with WordPress proficiency and has experience building APIs with Elixir/Phoenix.
Portfolio
Check
Python 3, Django, React
Leapfin
React, Scala, Java, Docker, Snowflake, PostgreSQL
Community.com
TypeScript, React, Cypress, Elixir
Experience
- Node.js - 7 years
- React - 7 years
- Angular - 6 years
- Elixir - 4 years
- TypeScript - 3 years
- GraphQL - 3 years
Availability
Part-time
Preferred Environment
Tmux, Linux, Vim Text Editor, Visual Studio Code (VS Code), Adobe Illustrator, Adobe Photoshop
The most amazing...
...thing I've developed was a land management system as a sole and later senior developer that grew as a product to serve enterprise-level businesses.
Work Experience
Software Engineer
2023 - 2024
Check
- Developed a report for employers to check the validity of their data, significantly decreasing the number of issues at tax filing time.
- Built in-depth documentation to help with the on-call process and tackle frequent tasks developers had to work on.
- Developed logic to export contractor data for sending tax documents and generating PDFs for 2023 tax documents.
Technologies: Python 3, Django, React
Lead Full-stack Engineer
2023 - 2023
Leapfin
- Built a UI library from scratch during a more extensive redesign.
- Upgraded legacy UI system with a new build system, better testing, better test helpers, and a new React version.
- Delivered in-depth documentation on front-end UI standards to get back-end developers up to speed.
Technologies: React, Scala, Java, Docker, Snowflake, PostgreSQL
Staff Software Engineer
2022 - 2023
Community.com
- Led web team in restructuring itself and tackling significant web tech debt and related initiatives.
- Built features for front-end applications, including the UI for client-side data modeling and filtering. This included TypeScript type modeling for robust type safety around arbitrary data.
- Helped make key architectural decisions for front-end applications, from providing input on cross-team initiatives to setting standards.
Technologies: TypeScript, React, Cypress, Elixir
Senior Software Engineer
2020 - 2022
Community.com
- Planned, oversaw, and implemented a large-scale refactor on a business-critical part of the front-end web React application from JavaScript and a Redux architecture to use TypeScript and React query.
- Led the web team and web team initiatives. Including merging a dozen front-end applications into a monorepo, which encouraged cross-collaboration and knowledge/code sharing across applications.
- Built an Elixir service for fetching and displaying website metadata for user-submitted links.
Technologies: React, Cypress, CircleCI, Elixir
Senior Engineer
2015 - 2020
Landdox
- Built a front-end single-page application in AngularJS and spear-headed efforts to migrate and hybridize into an Angular application, and then worked on rewriting the application from scratch in React and Redux.
- Decided on the stack, streamlined the dev workflow, worked on performance, and created a comprehensive test suite and a collaboration protocol. Developed application architecture.
- Managed project development and momentum and hired for the team in the initial years of the startup.
Technologies: PostgreSQL, Optical Character Recognition (OCR), Angular, AngularJS, React, Phoenix, Elixir, Node.js
Full-stack Development and Design
2005 - 2020
Freelance
- Speedily converted Photoshop and Illustrator designs to WordPress websites and implemented a performant workflow for the process.
- Designed numerous websites for small businesses and converted those into WordPress websites.
- Oversaw the deployment of web properties to servers.
- Developed sites in Wix, Squarespace, and Webflow for small businesses to showcase their portfolios and services and empowered them to make content updates.
Technologies: React, AngularJS, WordPress, Node.js, Adobe Photoshop, Adobe Illustrator
AngularJS Consultant
2014 - 2015
ZURB
- Built out the AngularJS side of an open-source product called "Foundation for Apps."
- Helped manage the open-source aspect of "Foundation for Apps."
- Worked on the popular Foundation CSS framework for bug fixing and bug triage.
Technologies: Gulp, Sass, AngularJS, JavaScript
Applications Developer
2013 - 2014
Consumer Media Network
- Developed an email remarketing aspect to the lead generation funnel.
- Developed high-performance APIs and front-ends to serve data to millions of users.
- Developed and tuned existing lead generation engine to increase conversion rates as well as performance.
Technologies: Ansible, Puppet, Chef, Vagrant, Ruby on Rails (RoR), Ruby, Node.js, Symfony, PHP, AngularJS
Lead Developer
2012 - 2013
PushFire
- Developed an internal set of tooling for others on the team to use.
- Managed project development from start to finish as well as tracked feature development.
- Utilized UX and UI popular design principles to improve application experience.
Technologies: PostgreSQL, Knockout (Knockout.js), Sass, Laravel, PHP
Front-end Developer
2012 - 2012
SIOPCO
- Developed a link-sharing feature with preview fetching for a social network.
- Established CSS architecture and patterns for others to follow.
- Developed a link preview aspect of a link-sharing social network.
Technologies: CSS, Knockout (Knockout.js), C#
Director of Development
2011 - 2012
Adhere Creative
- Developed and streamlined a WordPress development flow to increase productivity.
- Designed and presented website and logo designs for various companies in their rebranding process.
- Implemented up-to-date search engine optimization recommendations on WordPress sites and streamlined the SEO process for new projects.
- Implemented website designs in Hubspot -- a low-code, marketing-first CMS that allows users to easily update content on their own.
Technologies: Adobe Illustrator, HubSpot, CSS, WordPress, PHP
Experience
Hydra
A Node.js API back end that accessed and served multiple vast datasets (government data as well as custom-gathered data) that front-end developers could utilize to create rich and interactive applications. With heavy caching, it was able to support millions of users every month.
Tseczka Framework
https://github.com/AntJanus/Tseczka-Wordpress-ThemeA WordPress and CSS framework I developed in order to rapidly develop client projects as well as rapidly convert Photoshop/Illustrator files into premium WordPress websites. It handled everything from having a CSS framework to being SEO-compliant
Ng-Redux
https://github.com/angular-redux/ng-reduxI took over active development and open source community management for ng-redux, an AngularJS wrapper for Redux. I rewrote majority of the code to provide more flexibility to redux/angularjs users and was able to collaborate with other developers in order to increase the quality of the project
Foundation for Apps
https://github.com/zurb/foundation-appsI developed an AngularJS architecture for this rapid application prototyping framework. I collaborated with Zurb's best designers to create an easy-to-use toolkit for designers to build interactive AngularJS prototypes that could also be used by developers to further build on.
Tech.Pro
A social media website for developers to chat, ask questions, and look for work. I worked on an initial link-sharing feature and feed similar to how Reddit or HackerNews work which included backend work for storing the data, tagging, implementing search, and scraping submitted sites to retrieve an image, description, title, and other data for displaying to users utilizing C#.
I also worked on the voting part of the feature, structuring CSS for the entire site, and building KnockoutJS views to display the feed and the data.
I also worked on the voting part of the feature, structuring CSS for the entire site, and building KnockoutJS views to display the feed and the data.
PUCL Podcast Website
A niche podcast website that I fully redesigned from scratch, built in WordPress with a custom SASS/CSS framework I wrote on top of a custom WP theme, and deployed to a Digital Ocean server I created and supported for several years.
I worked on solving UI issues and performance problems present in the previous iteration to provide the best experience for visiting users.
I worked on solving UI issues and performance problems present in the previous iteration to provide the best experience for visiting users.
Education
2010 - 2012
Bachelor's Degree in Computer Science, Physics, and Math
University of Houston - Houston, TX
Skills
Libraries/APIs
Node.js, React
Tools
Adobe Photoshop, Adobe Illustrator, Vim Text Editor, Tmux, Gulp, Vagrant, Chef, Puppet, Ansible, CircleCI
Languages
CSS, Elixir, Sass, PHP, TypeScript, JavaScript, Ruby, C#, GraphQL, Scala, Java, Snowflake, Python 3
Frameworks
Bootstrap, Redux, Angular, Phoenix, AngularJS, Symfony, Ruby on Rails (RoR), Laravel, Knockout (Knockout.js), Cypress, Django
Platforms
WordPress, Linux, HubSpot, Visual Studio Code (VS Code), Docker
Storage
PostgreSQL
Other
Optical Character Recognition (OCR)
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