Stefan Annell

Technical Director at Mojang Studios

Stockholm, Sweden

steann87@outlook.com LinkedIn GitHub

Engineering leader
who ships great products.

I'm a software engineer turned technical leader with a mechatronics background and a passion for building strong engineering teams. After shipping Minecraft Dungeons and later working on its DLC and seasonal updates, I moved fully into technical leadership — focusing on clarity, collaboration, and scalable technical strategy in Unreal Engine.

I love helping teams grow, make smart decisions, and ship great products. Tech, people, and product — that's where I thrive.

10+
Years in software
6
Years at Mojang
3
Roles at Mojang
1
Research publication

Career timeline

Mojang Studios
6 years 3 months · Stockholm, Sweden
Technical Director
Current Aug 2024 — Present
  • Set the strategy and technical direction for Minecraft Dungeons II — defining how the team ships features in a fast, safe, predictable, and scalable way.
  • Partner with other discipline leads to align technical direction with the game's vision and requirements.
  • Lead the exploration of how to build AI-assisted workflows for the project, evaluating where they can support the team and how to integrate them into development.
  • Own performance targets across every release platform.
  • Lead and support other leaders, providing the clarity and direction that keep the whole project aligned.

Tech Lead
May 2022 — Aug 2024 · 2 yrs 4 mos
  • Led the Tech & Online branch of Minecraft Dungeons II, owning its technical strategy end-to-end.
  • Designed the online architecture for dedicated servers and full cross-play.
  • Built the game's localisation pipeline.
Senior Software Engineer
Apr 2020 — May 2022 · 2 yrs 2 mos
  • Worked on Minecraft Dungeons in Unreal Engine — leading the design and implementation of cross-platform play, live-ops seasons, entitlements, and other online services.
Netlight
2 years 2 months · Stockholm, Sweden
Software Developer
Apr 2020 — May 2022
FIS
2 years · Stockholm, Sweden
Software Developer
May 2018 — Apr 2020
ÅF
1 year 10 months
Software Developer
Aug 2016 — May 2018
Hartvik Engineering
9 months · Uppsala
Embedded Software Developer
Jan 2015 — Sep 2015

Summer and part-time embedded systems programming.

Core competencies

Technical Leadership Unreal Engine C++ C Java Online Architecture Cross-platform Play Live-ops Dedicated Servers Engineering Strategy Team Leadership Mechatronics Performance Optimisation Localisation Pipelines Embedded Systems Game Development

Building for fun.

WebTessellate main menu
Indie Game · Creator
WebTessellate

A browser-based factory-automation game where you place belts, machines, and hubs to route and transform shapes. Systems run continuously — the factory keeps working even when you're away. Engineered to stay smooth at scale.

TypeScript three.js WebGL2 AI
Meal Planning · Web & iOS
Matplan

A Swedish meal planner that turns recipe links or recipes entered by hand into a recipe library, meal calendar, and combined shopping list. Share plans on the web, estimate grocery costs at Willys, and send selected ingredients to Bring! or a Willys cart.

Meal Planning Recipes Shopping Lists iOS
Language Learning · Web & iOS
Gramatica

A Spanish grammar learning app for web and iPhone, built around short lessons, contextual exercises, and explained feedback. Tappable word meanings and spaced review help reinforce understanding, while the native SwiftUI app works entirely offline.

SwiftUI Spanish Grammar Spaced Review Offline
Driving Companion · iOS · In Development
Fast and Furious

Now called SpeedCue: an iOS driving companion that displays current speed and road speed-limit information in the app and a Live Activity. Built around a provider-neutral backend using Swedish OpenStreetMap road data, with an optional on-device plant garden powered by limit-aware driving distance.

iOS Live Activities OpenStreetMap Cloudflare
ecs-cpp template <typename... Cs> class Entity { // Cache-friendly component storage std::tuple<Cs...> components; template <typename C> C& get() { return std::get<C>(components); } };
Open Source · C++ Library
ecs-cpp

A header-only Entity Component System (ECS) for modern C++20. Components can be added to or removed from entities at runtime, with cache-friendly, arena-allocated storage for fast iteration. Built with templates and concepts to make misuse hard.

C++20 ECS Game Engine Open Source

Publication

Probabilistic Collision Estimation System for Autonomous Vehicles
Research paper · KTH Royal Institute of Technology · Mechatronics

Academic background

KTH Royal Institute of Technology
Master's Degree — Mechatronics
2014 – 2016
KTH Royal Institute of Technology
Civilingenjörsexamen — Mechatronics
2013 – 2016
KTH Royal Institute of Technology
Bachelor's Degree — Mechanical Engineering
2010 – 2014