Dejan Velimirovic
Full-Stack Software Engineer
Part of FatCat Coders since:
August 2020
Dejan is an experienced software architect and engineer with over 19 years in web technologies. He excels in product development across healthcare, finance, and SaaS solutions, and has led complex software architecture projects. Dejan is a great fit for you if you are seeking highly adaptable, versatile engineer and architect that has DevOps expertise.
Enjoy Good Health
Client ProjectJuly 2023 - ongoing
Clean and pure vitamin supplements are specifically designed for people who experience sinus and allergy problems.
Led the integration of Contentful CMS and Google Merchant Center, enabling efficient content updates and improving product visibility.
Implemented secure Stripe payment integration, ensuring compliance with American data privacy regulations and industry standards.
Developed a custom user review system and leveraged existing APIs for streamlined product management, reducing development time.
Established a scalable architecture for future growth, collaborating with a cross-functional e-commerce team under Scrum methodology.
Main tech stack:
Gatsby (Vercel), Contentful, Stripe,
ProvideHealth - Vitamed
Client Project)February 2021 - ongoing
ProvideHealth is an App created by doctors that offers custom product selections for your health needs.
Implemented a Custom Provider Share Medication Recommendation Process with Twilio SMS deep linking, boosting engagement and conversion rates.
Integrated Shippo for efficient order fulfillment and Stripe for secure, user-friendly checkout, ensuring compliance with industry regulations.
Developed a comprehensive admin panel for app owners, enabling full control over purchases, metrics, and product management.
Led a development team in optimizing the payment infrastructure for U.S. exclusivity, working within an m-commerce team under Scrum methodology.
Main tech stack:
NodeJS, NestJS, PostgreSQL, ReactJS, React Native, AWS, Stripe
ConvertMore
Client ProjectAugust 2022 - December 2022
A customizable widget that helps you get more customers from your current website visitors.
Enhanced the Convertmore service by adding new features and fixing bugs in a customizable widget for converting website visitors into customers.
Implemented key features such as Mexican phone number support, tracking, account deletion, phone number spoofing, and analytics integration.
Tackled complex technical issues, leveraging extensive experience as a key engineer on the team.
Collaborated closely with the Convertmore team, including the project manager and QA, to ensure smooth project execution.
Main tech stack:
NodeJS, PostgreSQL, ReactJS, AWS
Badi.rs
БадиJanuary 2022 - ongoing
Badi.rs is B2B software designed for eFiscalization purposes in Serbia. It serves as a modern platform for managing retail establishments, functioning as an advanced Electronic Sales Invoice Registry (ESIR) system.
Dejan led the entire development process for the Badi project, from conceptualization to deployment.
Badi includes key eFiscalization features such as product reporting, receipt exporting, and real-time stock management, with seamless third-party integration.
The project uniquely uses Golang to create the Electronic Sales Data Controls (ESDC) component, which signs fiscal receipts via a smart card and submits them to the Serbian Tax Authority.
Badi is accessible on Windows, macOS, Linux, and mobile web browsers, with a mobile app version currently in development.
Main tech stack:
NodeJS, PostgreSQL, ReactJS, Electron, Golang
TradeCo
TradeCorJanuary 2017 - February 2020
TradeCore is a platform-as-a-service provider that enables fintechs to build next-generation banking and investment products.
Developed a backend trading service platform accessible via API for other companies.
Led the development of a mobile app for trading cryptocurrencies.
Created features for a stock market web platform, including real-time pricing aggregation and modular architecture for flexible integration.Evolved to Lead Architect, managing feature planning and documentation, including a real-time notification system with Redis and Lua, and utilizing InfluxDB for fast data querying. Worked with a small team of two developers and one designer.
Main tech stack:
NodeJS, PostgreSQL, Redis, InfluxDB, AWS, ReactJS, React Native, Lua
ShiftPlanning / Humani
ShiftPlanning / HumanitSeptember 2011 - June 2016
ShiftPlanning is a B2B software solution for shift planning and workload coordination.
Initially made smaller changes to the product during its final stages.
Planned and developed a mobile web application from scratch to release.
Took on high-level managerial responsibilities, working closely with the hiring manager during the app development phase.
Led frontend development, focusing on a Single Page Application (SPA) using JavaScript and Can.js, and collaborated with the DevOps team to implement database replication for multi-server functionality.
Main tech stack:
PHP, MySQL, JavaScript, Redis, CanJS
WayI
WayIDOctober 2009 - May 2011
WayIDo was a social network for creatives to showcase portfolios in various multimedia formats such as videos, pictures, and music, similar to Facebook, with features including chatting, commenting, and interaction.
Conducted a full migration from PHP to C++ backend, ensuring backward compatibility and evaluating performance between PHP and C++.
Implemented a video chat feature using JavaScript and a Flash component, and developed a file conversion feature for social network compatibility.
Managed DevOps tasks, introduced functionalities in Redis, developed a Redis Client in PHP, and led the transition from Memcached to Redis.
Worked in a team of 6-8, including designers, a database developer, developers, and a DevOps engineer.
Main tech stack:
PHP, MySQL, JavaScript, Redis, C++, Java, Red5
MasCode
MasCoderMarch 2008 - September 2009
MasCoders was an outsourcing company for web page development in various industries and niches.
Primarily worked on web pages utilizing Drupal and Joomla frameworks.
Undertook a notable project involving the development of an Admin Panel resembling C-panel for a hosting company, alongside a custom solution tailored for a Dutch company's hosting management needs.
Collaborated within a team of 5 to 6 full-stack developers to deliver projects efficiently.
Main tech stack:
PHP, JavaScript, MySQL, Drupal, Joomla
First Beat Med
First Beat MediNovember 2005 - August 2008
First Beat Media was a web development company in the niche of advertising and the adult entertainment industry.
Implemented modifications to the internal advertising system, adapting ad formats for high-traffic webpages
Independently led the integration of a payment gateway.
Collaborated within a small team consisting of two developers and one manager.
Main tech stack:
PHP, MySQL, JavaScript
Masaryk University, Faculty of Informatics,
Brno, Czech Republic
English - C1 
Czech - B1
Owner of the PetShop “Moja Mačkica”
Founder of “DVSoftware”