Linas Ozeraitis, Developer in Vienna, Austria
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Linas Ozeraitis

Verified Expert  in Engineering

Augmented Reality (AR) Developer

Vienna, Austria
Toptal Member Since
October 20, 2017

Linas is a creative full-stack senior developer. With 10+ years of experience in a broad range of software development projects, he focuses intensely on productivity and quality. Linas looks at software development as a craft and constantly works on improving his skills and knowledge.


WebSockets, WebRTC, Mixed Reality Toolkit (MRTK), BIMserver, Xeogl, Three.js...
Docker, Firebase, GraphQL, REST, Angular, React, Webpack, HTML5, Node.js...
HoloLens, Unity3D, C#, Unity




Preferred Environment

JavaScript, TypeScript, WebXR, Virtual Reality (VR), Augmented Reality (AR), React, Git, Unix

The most amazing...

...I've built: a platform for real-time communication between users and an Arduino robot, playing piano while streaming from the John and Yoko suite in Amsterdam.

Work Experience

Founder | Technical Lead

2018 - PRESENT
  • Developed system architecture and implementation for a BIM-based augmented reality software for quality assurance in architecture, engineering, construction, and facility management industries.
  • Hired and managed back end, unity, and graphics development team. Was responsible for the strategy of further product development. Directly acquired new partners and potential clients.
  • Designed and implemented augmented reality "viewers" for iOS, Android, DAQRI, and Hololens (ARKit, ARCore, MRTK).
  • Designed and implemented a 3D front-end dashboard to view visualize 3D IFC facility models and the sensory/QA data associated with that facility.
  • Designed and implemented a back-end layer to enable CRUD and real-time communication for the IFC data.
  • Investigated and set up a JAVA based BIM server to act as an IFC to geometry converter and revision manager.
  • Developed a 'remote expert' application for Hololens and a web app.
Technologies: WebSockets, WebRTC, Mixed Reality Toolkit (MRTK), BIMserver, Xeogl, Three.js, GraphQL, React, Firebase, Node.js, HoloLens, ARKit, ARCore, Augmented Reality (AR), Unity

Freelance Developer

2017 - PRESENT
  • Created online interactive learning/skill testing tools for Austrian State Agencies.
  • Built an online local food delivery system.
  • Developed a system with real-time data mining, big-data management, and load balancing for an interactive navigation app.
  • Created a browser-based platform for realtime video conferencing.
Technologies: Docker, Firebase, GraphQL, REST, Angular, React, Webpack, HTML5, Node.js, JavaScript, Unity

Hololens Engineer

2020 - 2022
  • Developed a Hololens 2 application, creating holograms (drawings, annotations, animated objects, real-time measuring, and a hand recording) for video and image captures for a pharma 4.0 software company.
  • Created a Hololens 2 application to train lab workers on using a bio-reactor in a clean room.
  • Worked with the DevOps team to devise a solution to configure the Hololens app to use different APIs when installed via MDM (something Microsoft does not provide out of the box).
  • Used ArUco markers, azure object tracking, improved voice commands, and improved QR scanning functionality.
  • Created onboarding scenes teaching users how to employ the app and Hololens (MRTK) interactions, built UX solutions enabling better interaction experience to boost a worker's performance with the custom windowing system and user handedness selection.
Technologies: HoloLens, Unity3D, C#, Unity

Senior JavaScript Graphics Engineer (AR and 3D)

2019 - 2020
Non Disclosure Agreements Constraints
  • Developed a web-based augmented reality player with more than 500,000 views in the first months.
  • Optimized the WebGL rendering performance and the pipeline for faster loading of the 3D models.
  • Adapted the .basis/ktx format to get a massive reduction in GPU memory consumption.
  • Augmented the user experience with 3D special effects.
Technologies: Augmented Reality (AR), Three.js, React

Senior Software Developer

2014 - 2017
  • Designed and developed an augmented reality framework to be used on LAN connected devices.
  • Collaborated with "Volkswagen" on implementing augmented reality training scenarios for an assembly line (
  • Introduced and optimised new workflows to work with browser-based 2D and 3D content.
  • Working with Bank Austria implementing various tools, from interactive chart services ( to user interfaces for ATM machines for Bank Austria.
  • Collaborated with "Karlsruhe Institute of Technology" in implementing and testing principles of "Semantic web" in practical applications.
Technologies: NGINX, Apache, CSS, HTML5, JavaScript, Unity

Software Developer

2010 - 2014
  • Worked on various websites, including award-winning Austrian online Pavilion for World Expo.
  • Collaborated with "Steinway and sons" implementing award-winning online piano tool.
  • Consulted and worked on PHP code and MySQL routines optimisation to bring websites to blazing speed.
Technologies: AS3, Flash, Apache, CSS, HTML5, JavaScript

Senior developer

2009 - 2010
  • Led a team in building an online food delivery service.
Technologies: CSS, HTML, JavaScript, Apache

Freelance Web Developer

2003 - 2009
  • Worked with organizations from around the world, developing websites that include eCommerce, booking, portfolio, blog, and multilingual functionalities.
  • Increased traffic and enhanced page ranking by improving website structure, performing Search Engine Optimization (SEO) and Search Engine Marketing (SEM) for local improvements.
  • Developed UI/UX strategies that include wireframes and mockups and for small and medium-sized companies.
  • Designed and implemented .NET interface for local newspaper archiving platform.
  • Designed and developed several content management systems based on LAMP stack.
Technologies: JavaScript, Flash ActionScript, XML, HTML, .NET, Unity

Web Developer

2001 - 2003
IDEA "Interaktyvi reklama"
  • Built state of art (for that time) websites.
  • Developed and maintained in-house CRM and CMS.
  • Designed web-based games with Flash (AS2/AS3).
Technologies: JavaScript, HTML, Apache

AR-AQ-Bau — Use of Augmented Reality for Acceptance and Quality Assurance on Construction Sites
I developed an augmented reality application for quality assurance in the AEC industry.

The project consists of two main parts:
- The dashboard is a web app where the user can upload/view/manage their building information models (BIM).
- The augmented reality (AR) app is an app where the user can precisely position and track virtual models within the actual environment.

HoloLens Remote Expert
I developed and customized a remote-expert system for HoloLens and web platforms.
The remote expert enables a person to see and 'feel' the environment of another person wearing HoloLens.

- Two-way audio/video communication.
- Spatial geometry streaming from HoloLens and rendering in the web app.
- Freehand drawing tool in AR.
- Screen sharing: PC to HoloLens.
- File sharing: PC to HoloLens.
- Remote screen recording (record HoloLens video/audio/holograms and instantly save on remote PC).

Senior JavaScript Graphics Engineering (AR and 3D)

I developed a web-based augmented reality player with more than 500,000 views in the first months.
I also optimized the WebGL rendering performance and the pipeline for faster loading of the 3D models and adapted the .basis/ktx format to get a massive reduction in GPU memory consumption.

AR Research Project for VW
Research project for Volkswagen, implementing educational training with AR glasses for an assembly line.

React/Redux Page — Oegreissler
Oegreissler is a platform for farmers and their clients to provide the best experience for delivering local products to nearby neighborhoods.

Gentics Mesh UI
An Angular CLI-based UI for a headless content management system.

React/Redux Page — Online Test
A website for an Austrian state agency to test the skills of young people to determine if they are ready to become an entrepreneur.

Piano for Peace — Amsterdam
A live stream in memory of the legendary bed-in by John Lennon and Yoko Ono

On March 26, 2012, a live stream of the “Piano for Peace” campaign recalled the legendary bed-in by John Lennon and Yoko Ono in the Hilton Hotel in Amsterdam. The microsite linked the event with the online community. From March 23-25, users could play their songs via a virtual piano on the microsite and optionally save a picture of themselves.

Always up for a Challenge

It's a Chrome experiment with a Halloween cam. Transform your face into ghost mime using face detection and WebGL filters. It can be used for Chrome and Firefox only and needs good lighting conditions.

• Edit: Now Edge, Safari, Android, and iOS. For iOS, it only has image uploads.

Fluent in Manipulating Pixels on Your Browser

A browser-based game with some awesome nostalgia graphics and sounds.
It came out as a weekend project just for practicing game development on pixel shader skills. Graphics and audio used for the game were already in the public domain.

Stack used: JavaScript/Canvas/PhaserJS

Spermex | Educational Game
Spermex is an educational, tap-fast-as-you-can game for "Österreichische Gesellschaft für Familienplanung."



Sass, CSS, HTML5, C#, JavaScript, TypeScript, AS3, HTML, XML, Flash ActionScript, GraphQL, SQL, Java, Python


Angular Material, Unity3D, .NET, Angular, Unity, Redux, Chrome, ARKit


Three.js, WebXR, React, Node.js, WebRTC, WebGL, OpenGL


8th Wall SDK, Canvas, Angular CLI, Adobe Photoshop, HoloLens, Sketch, Git, Apache, NGINX, Flash, Webpack


Firebase, Docker, Unix, Visual Studio Code (VS Code), iOS, Android, ARCore


MongoDB, NoSQL


WebSockets, Augmented Reality (AR), Virtual Reality (VR), Mixed Reality Toolkit (MRTK), Basketball, Mixed Reality (MR), Xeogl, BIMserver, Games, Education, Browsers, HTTP Live Streaming (HLS), Headless Software, Artificial Intelligence (AI)


Unit Testing, REST, Testing

2005 - 2007

Bachelor's Degree in Computer Science

Vilnius Gedinimas Technical University - Vilnius, Lithuania

2001 - 2004

Bachelor's Degree in Computer Science

Vilnius Business College - Vilnius, Lithuania

2002 - 2003

Erasmus Exchange in Computer Science

University of Bedfordshire (Erasmus) - Luton, UK

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