Hi, my name is Andrej Gajdos

I’m a full stack developer, specialized in development of web applications using React, Gatsby, Node.js & more

Freelance Full Stack Web App Developer | Andrej Gajdos
Freelance Full Stack Web App Developer | Andrej Gajdos

ABOUT

I work with various industries all around the world to build amazing things for amazing people. I create fast, clean, and maintainable web applications, ready to scale from few users to thousands. I can help you deliver a seamless and engaging experience to your users. Background in computer science and ability as a full stack developer (front end and back end) allow me to create everything from small business websites to custom web applications.

I have over 6 years of experience in delivering web applications and I like making life better through technology. My work currently consists of freelance clients and side projects. My freelance full stack development roots are in React, Node.js and others.

I offer my services as a full stack developer for hire to work with businesses of all sizes. Feel free to get in touch. I’m available during the week to discuss and advise on your project or development needs. Schedule a call with me →

What is a full stack developer ?

A full stack developer has the functional knowledge and ability to take a concept and turn it into a finished product. A full stack developer should have knowledge in front end and back end development. Front end developers build the visible parts of applications that users see and interact with. Back end developers on the other hand, are responsible for building the parts the user does not see, which include core computational logic, server and database.
Front-end

JavaScript

HTML & CSS

Back-end
Others
  • Search engine optimization (SEO)
  • UI Prototyping
  • Designing RESTful APIs
  • Toptal – network of the best freelance software engineers
  • NA logo – custom Gatsby website
  • FA logo – React prototype
  • GLO logo – React Native project
  • SAY logo – full-stack platform
  • ZT logo – pre-sales engineer position
  • ATA logo – software engineer position
Toptal – network of the best freelance software engineers

Full-Stack Developer

September 2016 - Present
I joined the top 3% freelance software engineers to be able to work on amazing projects while striking the right work-life balance. My Toptal profile is available here.
  • Development tools:
  • Javascript
  • React
  • Node.js
  • PostgreSQL

React Developer

July 2018 - May 2019
  • Built company's fully responsive website.
  • Built customizable UI components used across multiple projects.
  • Built functional prototype of funds management and payments system in exchange platform.
  • Development tools:
  • Javascript
  • React
  • Gatsby
  • GraphQL
  • Styled-Components
  • Typescript

React Developer

May 2018 - July 2018
  • Designed and built a functional prototype of event management platform for managing swimming teams and swimming competitions.
  • Designed a new user interface based on customer’s prototypes.
  • Built a functional prototype from scratch as a single page application.
  • Development tools:
  • Javascript
  • React
  • Redux-Saga

React Developer

March 2018 - May 2018
  • Helped deliver a React Native project used for managing fitness studios.
  • Fixed various bugs and issues in the project.
  • Optimized the project for the Android platform.
  • Development tools:
  • Javascript
  • React Native
  • Redux

Full-Stack Developer

August 2017 - May 2018
  • Designed and built an interactive podcast platform.
  • Built a single-page app from scratch with a complex user interface, including user interactions and animations using React.js, Redux, D3.js, Webpack, SVG, and HTML5 Audio.
  • Designed and developed a RESTful API server using Heroku, Amazon S3, Node.js, Koa, PostgreSQL, and integration with Twitter API.
  • Podcasters can upload audio files and add 'spots' to specific moments in their podcasts, which can be anything from links, to social media posts, to other videos or images.
  • Listeners are engaged with content, such as social media posts or preview of external web pages.
  • Development tools:
  • Javascript
  • Node.js
  • Koa
  • Objection.js
  • Knex.js
  • React
  • Redux
  • D3.js
  • Heroku
  • Amazon S3
  • PostgreSQL
  • SVG
  • Webpack
  • Babel
  • Twitter API

Pre-sales Engineer

June 2016 - June 2017
  • Presented and demonstrated products to potential customers from all over the world.
  • Demonstrated product features to developer teams and showed how to use them in the development process with a specific workflow, environment, and toolset.
  • Helped sales associates close deals by presenting our products in specific use-cases.
  • Trained sales associates in how to effectively present and sell our tools to developer teams and managers.
  • Assisted customers with installation, troubleshooting, and other customer service for configuration issues.
  • Development tools:
  • Java

Software Engineer

April 2015 - June 2016
  • Implemented new features and fixed bugs in enterprise applications used for data quality management and rewrote UI components to use modern technologies.
  • Designed and implemented the front-end of an interactive web application for customer data management.
  • Designed and implemented server-to-sever communication and server pushes in a GWT application.
  • Development tools:
  • Javascript
  • Java
  • ES6
  • React
  • Flux
  • Immutable.js
  • Backbone.js
  • jQuery
  • Bootstrap
  • SCSS
  • Webpack
  • Gulp
  • Babel
  • D3.js
  • JSP
  • JSTL
  • JMS
  • ActiveMQ
  • Errai
LinkedIn Profile
  • auth-flow-spa-node-react
  • neo-transfer
  • newsfeed-cryptogoods
  • webpack-react
  • nested-datatables
  • svg-sprite-to-png
auth-flow-spa-node-react
User authentication in a single page application (SPA), built with Node.js and React. Local authentication – users can log in using username, passport and authentication through Facebook.
  • Development tools:
  • Javascript
  • Node.js
  • React
  • Redux
  • Redux-Saga
  • Passport.js
  • Koa.js
  • Oath
Neo-transfer allows you to login with a private key, see balance and transfer NEO or GAS within TestNet. Project is based on JS SDK for NEO blockchain.
  • Development tools:
  • Javascript
  • React
  • Redux
  • Redux-Saga
  • Neon
  • Blockchain
Newsfeed for events on cryptogoods. Single, responsive page for newsfeed. Polling occurs every 15s for new events to update newsfeed in real-time.
  • Development tools:
  • Javascript
  • React
  • Redux
  • Redux-Saga
  • Blockchain
  • Nonfungible
  • Cryptocollectibles
  • Polling
A sample project to demonstrate bundling ES6, React, SASS and Bootstrap with Webpack.
  • Development tools:
  • Javascript
  • React
  • Webpack
  • Bundling
  • Bootstrap
jQuery DataTables plugin for rendering nested DataTables in rows. Inner tables are independent of the data and layout from the outer table.
  • Development tools:
  • Javascript
  • Jquery
  • Datatables
  • Nested-structures
A gulp workflow converts SVG sprite into PNG images utilising Gulp.
  • Development tools:
  • Javascript
  • Gulp
Github Profile
Nash

Blazing fast static website built with React & Gatsby. All pages are fully responsive and optimised for mobile viewing.

DEVELOPMENT TOOLS
  • React
  • Gatsby
  • Styled-Components
  • Typescript
custom website of decentralized exchange | portfolio item
Saycaster (rebranded to Bitcast)

A podcast platform where podcasters can upload audio files and add 'spots' to specific moments in their podcasts. Podcasters can add anything from links, to social media posts, to other videos or images. Listeners are engaged with content, such as social media posts or preview of external web pages. I developed a RESTful API and built a single-page app from scratch.

DEVELOPMENT TOOLS
  • Node.js
  • PostgreSQL
  • Heroku
  • React
  • Redux
  • D3.js
full stack podcast platform | portfolio item
Andrej Gajdos

My website & freelance software development blog. Built with Wordpress & JavaScript.

DEVELOPMENT TOOLS
  • Wordpress
  • JavaScript
portfolio Andrej Gajdos | andrejgajdos.com
FastSwims

Event management platform for managing swimming teams and swimming competitions. I designed a new user interface based on customer’s prototypes and built a functional prototype.

DEVELOPMENT TOOLS
  • JavaScript
  • React
  • Redux
React prototype of event management platform | portfolio item
javascript portfolio item

THINGS PEOPLE SAY

After working with over a dozen developers from several different countries, it was absolutely refreshing to have had the pleasure to work with Andrej in building a full stack, dynamic web app.

Andrej has all of the required technical expertise that one could hope for when it comes to building a highly scalable and dynamic website. For me, this meant taking designs from an early stage and building the entire front and back end of the project, release ready.

He also exhibits a particular pride in his attention to detail (a trait which had been hard to find previously). This meant that after giving Andrej direction, you can always be confident that the code will be delivered exactly as required. Equally in my experiences, If Andrej see’s a better method, he will always suggest it, helping us end up with the best product possible.

All in all, Andrej was indispensable to our team and certainly one of the best developers that I have had the pleasure to work with.

Marcus Scott, Founder and Director of SayCaster (rebranded to Bitcast)

I had the pleasure of managing Andrej for about 1 year at Zeroturnaround. His natural ability to recognize deficiencies and address them made him an immediate asset to the team and the company.

Andrej would regularly think of different ways to provide our clients with the best grasp of the benefits that our tools offered. This allowed him to grow in respect from our clients and his co-workers. Andrej was a pleasure to work with and is always looking for ways to provide himself with personal growth.

Andrej also is an excellent orator. His clear and concise voice allowed customers to feel comfortable working with him and collaborating with him. This lead to his sales team being able to close many deals that they were previously unable to close.

I would love to be able to work with Andrej again someday and comes with my highest of recommendations.

Curtis Johnson, Sales Engineering Manager at ZeroTurnaround (acquired by Rogue Wave Software)

Andrej was a great help in creating a vision and front-end prototype for our startup. I have very little technical knowledge, and he was so knowledgeable in finding us technologies that would work for our needs. He is very professional, friendly, honest, and his communication is excellent. I highly recommend Andrej!

Carlene Takaki, Professional Swim Coach at Palo Alto Stanford Aquatics

SELECTED ARTICLES

How to Hire a Front-end Developer How to Hire a Front-end Developer Front-end developers are responsible for building the parts of applications that users see and interact with. (In most cases, front-end development refers particularly to web applications as interpreted by a user’s browser.) If we want to provide an engaging experience to our users, hiring good front-end developers is key. Over time, web user interfaces (UIs) have become more interactive. They have also spread to new contexts, like mobile, wearables, and cars. Front-end developers once easily mastered the three main technologies: HTML, CSS, and JavaScript. Read More →
A Guide to Managing Webpack Dependencies A Guide to Managing Webpack Dependencies The concept of modularization is an inherent part of most modern programming languages. JavaScript, though, has lacked any formal approach to modularization until the arrival of the latest version of ECMAScript ES6. In Node.js, one of today’s most popular JavaScript frameworks, module bundlers allow loading NPM modules in web browsers, and component-oriented libraries (like React) encourage and facilitate modularization of JavaScript code. Webpack is one of the available module bundlers that processes JavaScript code, as well as all static assets, such as stylesheets, images, and fonts, into a bundled file. Read More →
Authenticating Users in SPA using Node, Passport, React and Redux Authenticating Users in SPA using Node, Passport, React and Redux Implementing user authentication can be a difficult task, because we can use various libraries and authentication strategies. There are a lot of tutorials on this topic, but often times they miss fundamental information or don’t reflect set up of our project. In this blog post, I don’t attempt to write an universal tutorial for user authentication. However, I will point out some parts in authentication flow I didn’t find in other tutorials. We will be building a user authentication in a single page application with Node, React, Redux and Koa combined with Passport. Read More →
List of Free Online Tools For Front-end Web Development List of Free Online Tools For Front-end Web Development Often times, as a front-end developer you are required to do tasks, which are more related to web design. For instance, you are asked to make some animations, add “nice background colors”, “readable fonts”, etc. As an engineer, dabbling in anything related to web design can be both fun and frustrating. I use this list often when I develop front-ends. In this list you will find unique tools with a short description and a .gif preview or screenshot. I decided to make a preview of these tools, because if I want to use a specific tool, I remember only visual content of the tool, not the name or url. Read More →
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