Ari Arnbjörnsson's Avatar

Ari Arnbjörnsson

@flassari.bsky.social

Senior Software Engineer, Developer Relations at Epic Games. Former Lead Programmer on #Returnal for #PS5 @Housemarque. https://ari.games for my presentations!

1,661 Followers  |  134 Following  |  194 Posts  |  Joined: 22.10.2024
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Posts by Ari Arnbjörnsson (@flassari.bsky.social)

In-Engine · Double Fine's Keeper - Unreal 5 Exploration
YouTube video by Double Fine In-Engine · Double Fine's Keeper - Unreal 5 Exploration

Awesome video where @doublefine.com show you their in-engine Unreal workflows 😍 #uetips

www.youtube.com/watch?v=VMa5...

26.02.2026 09:29 — 👍 5    🔁 0    💬 0    📌 0
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That's how you get zero stutters in your game. You're welcome, game industry. #uetips

18.02.2026 13:27 — 👍 21    🔁 7    💬 1    📌 1
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Profiling with Purpose: Performance Lessons from a Real Unreal Project | Tutorial How does Epic Games’ Technical Developer Relations team profile games? Watch this session recorded at Unreal Fest Stockholm and learn our optimization...

The text version of "Profiling with Purpose: Performance Lessons from a Real Unreal Project" is up! Check it if you, like me, prefer text/images over videos for learning. #uetips

dev.epicgames.com/community/le...

18.02.2026 12:37 — 👍 28    🔁 5    💬 1    📌 1
The Technical Journey of Clair Obscur: Expedition 33 | Unreal Fest Stockholm 2025
YouTube video by Unreal Engine The Technical Journey of Clair Obscur: Expedition 33 | Unreal Fest Stockholm 2025

"Clair Obscur was 95% Blueprints"

I've been eagerly waiting for this talk to be uploaded, great job Tom and team 💪

youtu.be/t1CrbTx6O6w?...

14.02.2026 10:32 — 👍 35    🔁 7    💬 0    📌 1
Oops
Oops

I gave a talk on Slate in Unreal Engine as part of JetBrains GameDev Day, and the individual video is now up!
https://www.youtube.com/watch?v=1n3oIfI7nBM
#UnrealEngine

14.02.2026 10:25 — 👍 16    🔁 4    💬 0    📌 0
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Developing Large Procedural Systems with Low Friction and Fast Generation (Presented by Epic Games) | Agenda | GDC Festival of Gaming The GDC Festival of Gaming program blends expert insight with interactive formats designed to spark ideas, sharpen skills, and connect communities.

I'll be presenting with the awesome @highlyspammable.bsky.social
at the GDC26!! Come say hi :D

Developing Large Procedural Systems with Low Friction and Fast Generation (Presented by Epic Games) #GDC2026 #PCG #UE

schedule.gdconf.com/session/deve...

24.01.2026 18:28 — 👍 7    🔁 3    💬 0    📌 0
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Super early birds get the worms. The discount worms 🪱
200 worms! Or I mean, they get to not have those worms. Uhm...
Anyway, cheap tickets! 😅

Super-early bird pricing at $200 off for Unreal Fest Chicago are now available: unrealengine.com/events/unreal-fest-chicago-2026

21.01.2026 11:29 — 👍 2    🔁 0    💬 0    📌 0

The deadline for submitting talks for Unreal Fest Chicago is this Thursday, Jan 22nd! ⏱️

20.01.2026 13:02 — 👍 5    🔁 1    💬 0    📌 0
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Mastering Async Loading in Unreal Engine | Knowledge base This tutorial explains how async loading works and how to best leverage it.

Check out all the recent work that's been done to make async loading UObjects in the editor a reality. You can give it a try in 5.7:
dev.epicgames.com/community/le...

12.01.2026 14:23 — 👍 20    🔁 2    💬 0    📌 0
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Conferences can be super busy; it can be hard to find the time to eat dinner.
Fun fact: hors d'oeuvres can be a dinner if you just eat enough of them! 🤯

Pic related: me gobbling down finger food while the other person talks.

02.01.2026 14:59 — 👍 5    🔁 0    💬 0    📌 0
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The Great Hitch Hunt: Tracking Down Every Frame Drop | Tutorial Hear ye, developers! A scourge plagues our beloved industry. Grab your pitchforks and rally with Ari “the Hitch Hunter” Arnbjörnsson as he arms you with...

This guide complements The Great Hitch Hunt presentation really well, also check that out if you haven't already: dev.epicgames.com/community/le...

16.12.2025 08:58 — 👍 1    🔁 0    💬 0    📌 0
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Level Streaming Hitching Guide | Tutorial Guide to recognizing common level streaming hitches in your Unreal Insights captures and tips and links to resources to address them. Hitches refers to ...

My coworker Zhi Kang Shao just published the Level Streaming Hitching Guide, a huge resource on the things you can do to prevent hitches during level streaming.

Read it here: dev.epicgames.com/community/learning/tutorials/qpll/unreal-engine-level-streaming-hitching-guide

16.12.2025 08:58 — 👍 7    🔁 2    💬 1    📌 0
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Unreal Fest 2026 is coming to Chicago next June, and I want YOU to present there!

Call for proposals is open until January 22nd, speakers get free hotel accommodation and conference tickets 🤘

Apply here: unrealengine.com/news/apply-to-present-at-unreal-fest-chicago-2026

I hope to see you there!

16.12.2025 08:44 — 👍 1    🔁 0    💬 0    📌 1
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Level Streaming Hitching Guide | Tutorial Guide to recognizing common level streaming hitches in your Unreal Insights captures and tips and links to resources to address them. Hitches refers to ...

Another one for my #UnrealEngine required reading list: dev.epicgames.com/community/le...

15.12.2025 18:47 — 👍 8    🔁 3    💬 0    📌 0

Oh god 😅

15.12.2025 12:19 — 👍 1    🔁 0    💬 1    📌 0
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"Mafia: The Old Country: Using MetaHuman in a AAA Character Pipeline" is a fantastic talk on Hangar 13's use of MetaHuman for their amazing-looking characters! 🤩

Watch it here: youtube.com/watch?v=V8rL1r_1IcQ

15.12.2025 12:13 — 👍 4    🔁 0    💬 0    📌 0

Ari and I both said a lot of words on stage at #UnrealFest Stockholm, and I think these are the most important. How to think about profiling, how to read the unicorn barf that is Unreal Insights, and tips for looking at GPU captures.

11.12.2025 13:56 — 👍 12    🔁 6    💬 2    📌 0
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Wow, perfect timing! I was just writing up some info on that internally for my teammates 😄
See image. The link goes here: dev.epicgames.com/documentatio...

12.12.2025 15:05 — 👍 3    🔁 0    💬 1    📌 0
Profiling with Purpose: Performance Lessons from a Real Unreal Project | Unreal Fest Stockholm 2025
YouTube video by Unreal Engine Profiling with Purpose: Performance Lessons from a Real Unreal Project | Unreal Fest Stockholm 2025

How do we profile games at Epic Games? Check out this presentation where @mattoztalay.bsky.social and I examine perf captures from Arctic Hazard's "NORSE: Oath of Blood" and show you how to use Unreal Insights and PIX.
www.youtube.com/watch?v=C-Aj...

11.12.2025 12:30 — 👍 18    🔁 2    💬 0    📌 1

Hæ from Reykjavík! Huge thanks to @flassari.bsky.social for being part of the very first Reykjavík Game Summit, and for capturing this great moment along the way! 📸

05.12.2025 21:59 — 👍 5    🔁 2    💬 0    📌 0

There are no stupid questions!
That's basically what's already happening. They shouldn't get compiled every game start, they get cached by the GPU driver. UE still needs to send those requests to make sure every one of them is still cached, but it's much faster on subsequent runs.

05.12.2025 12:57 — 👍 1    🔁 0    💬 1    📌 0
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When an Unreal 5.3+ game runs, it will immediately kick off precompilation of global shaders. You should wait for that to complete before starting the game, otherwise you'll likely get hitches. You do that with the NumPrecompilingPSOsRemaining node. #uetips

04.12.2025 12:01 — 👍 69    🔁 7    💬 1    📌 0
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I got to be a part of history! Super grateful to be able to participate on stage at Reykjavík Game Summit's inaugural conference 🤩
"Hi from Reykjavík!" 👋

03.12.2025 10:51 — 👍 4    🔁 0    💬 0    📌 1
New GPU Profiler and RHI Submission Pipeline | Unreal Fest Stockholm 2025
YouTube video by Unreal Engine New GPU Profiler and RHI Submission Pipeline | Unreal Fest Stockholm 2025

I've been waiting on this one! See how to use our new and immensely powerful GPU profiler in Unreal Engine 5.6+, and how it helps you debug GPU crashes! #uetips

www.youtube.com/watch?v=vnbA...

03.12.2025 09:02 — 👍 13    🔁 2    💬 1    📌 0

I was not able to make it to Unreal Fest Stockholm, but thanks to @flassari.bsky.social I still ended up on stage!

You can find me at 1:50:46 in the video, when I show the Unreal asset browser feature to rotate thumbnails of 3D assets.

30.11.2025 14:27 — 👍 10    🔁 4    💬 1    📌 0
101 Unreal Engine Tips & Tricks: The Reckoning | Unreal Fest Stockholm 2025
YouTube video by Unreal Engine 101 Unreal Engine Tips & Tricks: The Reckoning | Unreal Fest Stockholm 2025

We attempted to cram over 100 #uetips into a single presentation at Unreal Fest Stockholm. Did we succeed? Find our right here 👇
www.youtube.com/watch?v=4w0P...

30.11.2025 09:43 — 👍 15    🔁 3    💬 1    📌 1
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We managed to fill the room at CCP Games for the Reykjavík Unreal Engine Evening, no wonder with those banger presentations 🤩
"Hi from Reykjavík!" 👋

29.11.2025 09:27 — 👍 13    🔁 1    💬 0    📌 0
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Did that Super Mario Galaxy movie trailer get your nostalgia running? Feel like getting it out of your system by creating something? Why not start with the Custom Gravity tutorial, it will make for a great base for tiny planet hopping!
🌍🏃‍♂️‍➡️🌏

dev.epicgames.com/community/le...

14.11.2025 15:29 — 👍 9    🔁 1    💬 0    📌 0
Unreal Engine 5.7 MEGAPLANTS Crash Course #ad
YouTube video by William Faucher Unreal Engine 5.7 MEGAPLANTS Crash Course #ad

UE 5.7 is out, featuring our new Megaplants plugin: procedural instanced nanite skeletal meshes that voxelize in the distance 👀

@williamfaucher.bsky.social just released a great "getting-started" tutorial on it:
www.youtube.com/watch?v=3f7m...

13.11.2025 12:19 — 👍 30    🔁 6    💬 3    📌 1