Andro is available for hire

Andro Mikulić

Verified Expert in Engineering

Full-stack Developer

Zagreb, Croatia

Toptal member since October 28, 2021

Expertise

Algorithms Back-end Developers Full-stack Game Development Front End Integration Interim CTOs API Web Development C#

Bio

Andro is a full-stack and Unity developer specializing in scalable web platforms, high-performance interactive applications, and cross-platform game development. He builds robust systems end-to-end: from modern front-end and back-end architectures to optimized 3D experiences, with a strong focus on performance, clean architecture, and shipping production-ready products.

Portfolio

VNTANA

React, Tailwind CSS, HTML, JavaScript, TypeScript, Vite, Single Sign-on (SSO)...

Self-employed

C#, .NET, Java, Google Cloud, Git, Solution Architecture, Unity, TypeScript...

iScape Holdings Inc.

Unity, Android, iOS, Flutter, AI Tools, Claude

Experience

C# - 14 years
Unity - 14 years
Node.js - 12 years
TypeScript - 12 years
Software Architecture - 12 years
Full-stack Development - 9 years
React - 7 years
NestJS - 6 years

Preferred Environment

Node.js, C#, TypeScript, React, Unity, Next.js, NestJS

The most amazing...

...software I've developed is a back-end system that serves music data and metadata to 500,000+ monthly users, plus businesses and venues for Rock My World Media.

Work Experience

Senior Front-end Developer

2025 - PRESENT

VNTANA

Implemented white labeling across the platform, ensuring visual and functional consistency across all ecosystems. The implementation allows for fully customizable color palettes, along with various toggleable feature flags and labels.
Implemented the Lexical rich text editor along with attachments, mentions, and various other styling tools. This replaced the legacy CK editor, saving the company thousands in licensing fees.
Modernized the platform by implementing atomic design, cleaning up deprecated and broken components and fixing visual bugs.
Contributed to product discussions, recommended UX features that got accepted, guided non-technical members to better understand issues, and proposed solutions.

Technologies: React, Tailwind CSS, HTML, JavaScript, TypeScript, Vite, Single Sign-on (SSO), Full-stack, SaaS, Webhooks, Web Development

Educational Content Creator

2020 - PRESENT

Self-employed

Created Unity tutorial videos on game-related topics, from basic Unity components like transform and collider to more advanced topics like AI and real-time weather.
Ran a YouTube channel, acquiring and demonstrating skills in audio and video setup and recording, video editing with DaVinci Resolve, and audio mastering.
Grew my channel, youtube.com/c/rumpledcode, to 1,500 subscribers and 100,000 video views without marketing.

Technologies: C#, .NET, Java, Google Cloud, Git, Solution Architecture, Unity, TypeScript, Unity3D, API Integration, REST APIs, Data Structures, Object-oriented Programming (OOP), DigitalOcean, Front-end, Cloud Firestore, JSON, Software Architecture, GitHub, Software Design

Unity Developer

2024 - 2026

iScape Holdings Inc.

Developed a cross-platform gardenscaping app using Unity, which was fully compatible with existing native iOS and Android apps, importing and exporting modified compatible data.
Implemented the app in embed mode—the entire app was wrapped by a Flutter application written by a different team member, and had complete communication with it. This allowed for great flexibility in terms of deployment and UI.
Proposed and implemented various UX elements, processes, and functions on the Unity side to improve user flow.
Designed and developed a smart caching system, managing both in-memory cache and local storage. Implemented smart hashing of various data to cache runtime-generated textures.
Implemented cross-session AR experiences using Google Cloud Anchors, allowing users to share the same AR world across all platforms.

Technologies: Unity, Android, iOS, Flutter, AI Tools, Claude

Lead Back-end Developer

2021 - 2026

Rock My World

Improved user experience by decreasing loading times by 2x and reducing infrastructure costs by reorganizing and redesigning the database model.
Enhanced security and user safety, as well as prevented attempted intrusions, by applying the latest best practices missing in the legacy back-end systems.
Implemented automatic payment, CRM, and Slack hooks that reduced workload for the entire team, automating workflows and increasing sales acquisition.

Technologies: NestJS, Node.js, TypeScript, PostgreSQL, Back-end, MySQL, HTTPS, Technical Leadership, Slack, Project Management, Express.js, REST APIs, Git, SQL, Solution Architecture, Networking, Encryption, API Integration, Leadership, JavaScript, Linux, HTML, CSS, Docker, Microservices, REST, Security, API Development, Team Leadership, API Documentation, Databases, React, Data Structures, Object-oriented Programming (OOP), MERN Stack, API Architecture, Next.js, Full-stack, TypeORM, Back-end Development, Front-end Development, Full-stack Development, JSON, APIs, Software Architecture, Cloud, Database Modeling, GitHub, Stripe API, Stripe, Data Architecture, Amazon Web Services (AWS), Redis, Web Applications, Web Development, Algorithms, Payment Gateways, Stripe Checkout, Architecture, Authentication, Shopify, Shopify API, Integration, Email, Technical Requirements, Software Design, Webhooks

Technical Lead

2024 - 2024

Gryd Digital Media LTD

Developed a WebGL MVP for apartment touring using 360 pictures with Unity and C#.
Implemented a minimap system that maps 1:1 with the actual space and keeps check of the point of view.
Optimized the bundle size and compressed images, making the build around 20% smaller than source pictures while still preserving quality.
Allowed for fully customizable starting positions and shareable links that hold the complete state of the 360 virtual tour via URL query parameters.
Implemented a simple and easy-to-use system for tour management, allowing for quick (O(1)) reference to all data, reducing loading times, and improving user experience.

Technologies: Three.js, React, Augmented Reality (AR), 3D, Web Architecture, JavaScript, REST, Integration, Technical Requirements, Software Design

Unity and AR Developer

2023 - 2023

LightboxStudio

Improved performance, reduced loading time, and added version control and automatic deployment systems. Fixed several issues with the existing project.
Developed a web AR app that automatically applies textures to furniture models and places that model into the AR scene with complete controls like scale and rotate.
Implemented automatic QR code generation and embedded various material and model data to streamline the user experience from the furniture configurator to the web AR app.

Technologies: Augmented Reality (AR), WebGL, WebXR, Unity, C#, Full-stack, JSON, Software Architecture, Mobile Game Development, iOS, GitHub, Web Applications, Web Development, Algorithms, Android, Mobile Development, Integration, Technical Requirements, Software Design

Senior Back-end Node.js Engineer

2023 - 2023

Kickstage

Developed API endpoints and features that track and calculate energy consumption and CO2 emissions for each machine, machine category, and location for the Mymuenet portal (www.mueller-frick.com/technologies/digital-solutions/mymuenet/).
Boosted code output and reduced debugging time by improving the project's code consistency. Implemented project-wide formatting and linting standards, including pre-commit hooks for automating the entire pre-commit process.
Participated and contributed to business logic and features discussion and decisions in meetings.
Increased feature development speed by creating quick mock API endpoints so front-end developers could build their side in tandem with the back-end team.

Technologies: JavaScript, TypeScript, Node.js, GraphQL, Docker, PostgreSQL, Sequelize, Knex.js, Express.js, TypeORM, Back-end Development, JSON, APIs, Software Architecture, Cloud, Database Modeling, GitHub, Data Architecture, Redis, Algorithms, Architecture, Authentication, Integration, Technical Requirements, Software Design, Agile, SaaS

Senior Unity Consultant

2022 - 2022

Mobeus

Improved user retention and client satisfaction by building pixel-perfect UIs according to Figma specifications.
Increased development speed by applying audio controls in the settings page to be used throughout the app, enabling other developers to focus on more important tasks.
Collaborated with 10+ developers to implement core product features.

Technologies: Unity, C#, .NET, WebGL, Unity3D, REST APIs, API Documentation, Databases, Data Structures, Object-oriented Programming (OOP), Front-end, JSON, APIs, Software Architecture, Cloud, iOS, GitHub, Mobile Development, Integration, Technical Requirements, Software Design, Mobile

Senior Unity Developer

2022 - 2022

Jadu

Enhanced development speed by developing the core audio system to facilitate easier audio handling for other developers.
Increased user retention, decreased dropoffs, and reduced app storage size by implementing smart caching systems for audio data.
Improved user experience and increased engagement by fixing core issues and bugs.

Technologies: Unity, C#, Unity3D, Slack, REST APIs, Git, API Integration, .NET, REST, 3D Games, Augmented Reality (AR), Databases, Data Structures, Object-oriented Programming (OOP), Front-end, Web 3.0, Game Development, JSON, APIs, Software Architecture, Cloud, Mobile Game Development, iOS, GitHub, Android, Mobile Development, Integration, Technical Requirements, Software Design, Mobile

Senior Unity Engineer and Consultant

2021 - 2022

TuringSense

Improved realism and user experience significantly by developing a new and improved algorithm that reduced avatar glitching and pass-through, also known as avatar inner body penetration.
Enhanced and implemented new UI elements for all versions of the mobile app.
Implemented stat tracking using local and API data, which gamified the app flow and made the users more involved in the product, increasing retention and engagement.

Technologies: Unity, Unity3D, API Integration, .NET, C#, WebGL, REST, Security, REST APIs, Databases, Data Structures, Object-oriented Programming (OOP), Front-end, JSON, APIs, Software Architecture, Cloud, iOS, GitHub, Data Architecture, Algorithms, Android, Mobile Development, Integration, Technical Requirements, Software Design, Mobile

Lead Software Developer

2016 - 2022

Murphy Bevelacqua Consultants and Associates, LLC

Enhanced knowledge retention and learning speed significantly for hazardous materials (hazmat) trainees by developing 3D educational simulations, each with its unique scenario and 3D environment.
Allowed weaker and old hardware (iPads) to run the simulations by introducing smart optimization techniques.
Increased sales by recording videos and images from the 3D space to be used in the hazmat educational book as promotional material.

Technologies: Unity, C#, WebGL, Technical Leadership, Project Management, REST APIs, Git, Solution Architecture, Leadership, Node.js, .NET, JavaScript, REST, Unity3D, Virtual Reality (VR), Augmented Reality (AR), API Development, Team Leadership, API Documentation, Data Structures, Object-oriented Programming (OOP), Front-end, MERN Stack, WebSockets, Python, Swift, Full-stack, Firebase, Back-end Development, Full-stack Development, JSON, Software Architecture, GitHub, Algorithms, Authentication, Android, Mobile Development, Integration, Technical Requirements, Software Design, Mobile

CTO and Co-founder

2018 - 2021

Double Lens Solutions

Increased client conversion and boosted sales by creating sophisticated and hyper-realistic VR walkthroughs of unbuilt real estate using Unreal Engine.
Led the development of a website's front end for a large real estate investor, attracting an average of 4,000 unique monthly visitors.
Built a VR experience using Unity for the Faculty of Forestry in Zagreb. The experience featured six scenes, each showing the progression of climate change and its effects.
Consulted and led the entire IT infrastructure for a massive real estate project, including a website, emails and other communication, VR walkthroughs, and sales data.

Technologies: Unity, C#, HTML, CSS, JavaScript, Solution Architecture, Linux, C++, Networking, C, Encryption, API Integration, CTO, Leadership, .NET, WebGL, REST, Unity3D, Virtual Reality (VR), Security, API Development, Team Leadership, Fintech, REST APIs, API Documentation, MySQL, Java, Databases, Data Structures, Object-oriented Programming (OOP), DigitalOcean, Front-end, Web 3.0, MERN Stack, Game Development, Cloud Firestore, WebSockets, Python, API Architecture, Express.js, Full-stack, Firebase, Back-end Development, Full-stack Development, Front-end Development, JSON, APIs, Software Architecture, Cloud, Database Modeling, iOS, HLSL, 3D Games, GitHub, Stripe API, Stripe, Data Architecture, Redis, Web Applications, Web Development, Algorithms, Payment Gateways, Architecture, Authentication, Unity2D, Android, Mobile Development, Integration, Technical Requirements, Software Design, Mobile

Lead Game Developer

2019 - 2019

STEM Games

Designed and developed the client side of the game for the Technology Arena at the 2019 STEM Games event. Making the experience more engaging for competitors made the event more impactful.
Collaborated and assisted the back-end developers of the Technology Arena game, streamlining the entire process and allowing the competitors to focus on the competition.
Set up a local network at the event to grant everyone internet access. Peak network usage was around 1,000 concurrent users.

Technologies: Unity, C#, REST, Solution Architecture, Networking, API Integration, Leadership, .NET, JavaScript, HTML, TypeScript, Unity3D, HTTPS, 2D Games, Team Leadership, REST APIs, Databases, Data Structures, Object-oriented Programming (OOP), Front-end, Game Development, JSON, APIs, Software Architecture, Mobile Game Development, 3D Games, GitHub, Authentication, Unity2D, Technical Requirements, Software Design

Software Consultant and Developer

2018 - 2019

Smart Lumies

Developed games shipped for the Smart Toy app. Coached the junior game designer in preparing the documentation for a cleaner and simpler development process.
Created a data pipeline as a bridge for sending Bluetooth information from the iOS native app and embedded Unity game.
Mentored a junior Swift developer and a junior Unity developer, enabling them to perform better and increase their development speed and quality.
Increased process speed and reliability by consulting on best practices for game development and software architecture to deliver better and quicker results.

Technologies: Unity, C#, Swift, Linux, Networking, API Integration, .NET, HTML, CSS, WebGL, REST, TypeScript, Unity3D, Back-end, 2D Games, 3D Games, Augmented Reality (AR), API Development, Team Leadership, REST APIs, API Documentation, Java, Data Structures, Object-oriented Programming (OOP), DigitalOcean, Front-end, Game Development, Full-stack, JSON, APIs, Software Architecture, Cloud, Mobile Game Development, iOS, GitHub, Data Architecture, Web Applications, Web Development, Algorithms, Android, Mobile Development, Integration, Technical Requirements, Software Design, Agile, Mobile

Senior Node.js Developer

2018 - 2019

Kickstage

Developed the authentication microservice for the Wintrado forex platform using Node.js, taking that load off other services and allowing for faster development.
Contributed to the messaging implementation of RabbitMQ for the microservices used by the Wintrado forex platform, which increased the stability and uptime of the entire system.
Tracked and fixed bugs in multiple microservices with the help of Sentry, making the user experience cleaner and more consistent.

Technologies: Node.js, RabbitMQ, Docker, Microservices, Linux, Networking, Encryption, API Integration, JavaScript, SQL, HTML, REST, PostgreSQL, TypeScript, Back-end, HTTPS, Security, API Development, Fintech, REST APIs, API Documentation, Databases, Data Structures, Object-oriented Programming (OOP), DigitalOcean, MERN Stack, Cloud Firestore, WebSockets, API Architecture, Express.js, TypeORM, Back-end Development, JSON, APIs, Software Architecture, Cloud, Database Modeling, GitHub, Data Architecture, Amazon Web Services (AWS), Redis, Algorithms, Architecture, Authentication, Integration, Technical Requirements, Software Design, Agile, SaaS

Experience

Unity Gravity Simulation

https://github.com/AndroMikulic/GravitySimulation

A gravity simulation that I designed and developed in Unity using compute shaders to simulate thousands of bodies without lag. Using Newton's gravitational pull formula, the simulation calculates gravity between all bodies in each frame and applies the resulting forces.

STEM Games | Technology Arena Client Game

https://github.com/AndroMikulic/STEM-Games-Technology-Game

A project to gamify the Technology Arena competition at the 2019 international STEM Games. The players use this text-based game to navigate a maze with hidden programming challenges. I developed it using Unity and connected it to the back-end REST API, which was also created for the game. The project was a huge success, and we received plenty of kind words and compliments for the operation.

Full-stack Multiplayer Unity and Server Development

https://github.com/AndroMikulic/Unity-Multiplayer-City-Builder

Designed and developed an example of a multiplayer city-building game in Unity as a part of a tutorial series published on YouTube. The technologies used were Unity, .NET, SQLite. The project is open-source and available for download on GitHub.

Portfolio Website

https://rumpledcode.com

I developed my portfolio website using React and Next.js. The website was built as a static website that has all pages pre-rendered. It features analytics, dynamic page generation from data, and a responsive design.

VoxBox | A MagicaVoxel Asset-sharing Platform

https://voxbox.store/

VoxBox is a MagicaVoxel asset-sharing platform where users can easily upload and share their .vox 3D models. The site includes registration, email verification, model upload and edit functions, a rating system, and featured content.

Education

2019 - 2021

Master's Degree in Information Technology

University of Zagreb, Faculty of Electrical Engineering and Computing - Zagreb, Croatia

2014 - 2019

Bachelor's Degree in Software Engineering

University of Zagreb, Faculty of Electrical Engineering and Computing - Zagreb, Croatia

Certifications

JUNE 2013 - PRESENT

C1 English

University of Cambridge

Skills

Libraries/APIs

Node.js, REST APIs, API Development, Stripe API, WebGL, React, WebXR, Stripe, Shopify API, Three.js, Mantine

Tools

GitHub, Slack, Git, Stripe Checkout, Shadcn, RabbitMQ, Sequelize, Knex.js, Claude

Languages

C#, JavaScript, TypeScript, HTML, CSS, Java, C, Python, GraphQL, SQL, C++, Swift, HLSL

Frameworks

Unity, .NET, NestJS, Unity3D, Express.js, Unity2D, Next.js, Tailwind CSS, Material UI, Flutter

Paradigms

REST, Object-oriented Programming (OOP), API Architecture, Microservices, Mobile Development, Agile, Web Architecture

Platforms

iOS, Mobile, Linux, DigitalOcean, Firebase, Amazon Web Services (AWS), Android, Docker, Shopify, Mailgun

Storage

PostgreSQL, Databases, JSON, Database Modeling, MySQL, Cloud Firestore, Redis, SQLite, Google Cloud

Industry Expertise

Project Management

Other

Back-end, Solution Architecture, Networking, API Integration, CTO, 3D Games, Security, Team Leadership, API Documentation, Data Structures, Front-end, Game Development, WebSockets, Full-stack, TypeORM, Back-end Development, Full-stack Development, APIs, Software Architecture, English, Mobile Game Development, Data Architecture, Web Development, Algorithms, Architecture, Authentication, Integration, Email, Technical Requirements, Software Design, HTTPS, Technical Leadership, Encryption, Leadership, 2D Games, Virtual Reality (VR), Augmented Reality (AR), MERN Stack, Cloud, Web Applications, Payment Gateways, AI Tools, Single Sign-on (SSO), SaaS, Webhooks, Fintech, Web 3.0, Front-end Development, 3D, Vite

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