Unity 6.6 is now available

[u/unitytechnologies]

Howdy everyone! Your friendly neighborhood Community Man Trey here to share the news that Unity 6.6 is now available!

This is a Supported release. So, for those of you who don’t know what that means, it carries the same stability and critical update commitments as our LTS versions. 

One heads up before the feature list, because it changes how the Editor behaves out of the box: the default setting for entering playmode is now reload scene only for all new projects. Code won't reload and static state won't reset between runs. Existing projects keep whatever you've already got set. It's the biggest workflow change in the release, and it's deliberate prep for Unity 7, where domain reloads go away entirely. If you're planning that migration, making your code domain-reload-safe now is the cheapest time to do it. There's a technical upgrade guide on Discussions if you want the details.

Beyond that, here's a taste of what's in there:

• Native Dictionary Serialization: put [SerializeField] on a dictionary field and it just works, with a two-column key/value layout in the Inspector and a compile-time analyzer that flags unsupported key or value types
• Content Directories: load and hold only the assets a scene actually needs instead of whole bundles, using the same Addressables API you already have. Existing AssetBundle groups convert with a right-click, and AssetBundles aren't going anywhere for remote content
• Build Analysis window: build history plus views for your largest assets, long dependency chains, per-step timings, and the actual root cause of a failed build instead of all the surrounding noise
• Shader Build Settings: opt into DXC for DX12 (Shader Model 6, wave intrinsics, native 16-bit) and let Unity convert keywords into dynamic branches. A clean build of Survival Kids went from 1 hour 46 minutes down to 32 minutes with that turned on
• New Hierarchy window is now on by default: better performance in large scenes, horizontal scrolling, reorderable custom columns, public APIs for extending it, and support for non-GameObject items. The legacy window is still there if you'd rather stay put
• Unity Compute Light Baker: lightmaps, light probes, and adaptive probe volume data now bake through Unity compute shaders and the Unified Ray Tracing API, so baking can lean on hardware-accelerated ray tracing where you've got it
• 2D: rendering layer support for 2D lights on top of sorting layers, 2D shadows that finally work with GPU skinning, and new Profiler modules for 2D Animation, Tilemap, and 2D Graphics
• Web: WebGPU is production ready, which brings compute shaders, GPU skinning, indirect rendering, and VFX Graph to browser builds. WebGL 2 is still the default until you opt in. Also Progressive Asset Loading for per-scene downloads instead of one big upfront pull, and WebAssembly64 for projects that need to go past the 4 GB heap ceiling
• UI: a SafeArea component for uGUI that keeps content clear of cutouts and gesture areas without per-device margins, max width and height on layout elements, and backdrop-filter in UI Toolkit for frosted glass and dimmed overlays with no render textures or custom shaders
• Package signing for .unitypackage: publishers can sign .unitypackages so you can confirm authorship and that its contents haven't been tampered with after publishing

All the details are in the Discussions post. Feel free to head there to ask questions of the experts, or here and I’ll do my best to chase down what I don’t know.

Cheers,
- Trey
Community Man @ Unity

[u/Mechabit_Studios]

Native Dictionary Serialization

dang, it's been a long time coming

[u/unitytechnologies → u/Mechabit_Studios]

https://giphy.com/gifs/FoH28ucxZFJZu

- Trey
Community Man @ Unity

[u/DoctorShinobi → u/unitytechnologies]

[u/unitytechnologies → u/DoctorShinobi]

https://giphy.com/gifs/tBARTh0PZ6XCMlVEhi

- Trey
Community Man @ Unity

[u/P0mdap → u/Mechabit_Studios]

https://giphy.com/gifs/IxLeSDtUaZRmSiyCTf

[u/yoitstoast → u/Mechabit_Studios]

i’m not usually one to jump on the latest versions but this has had me chomping at the bit for 6.6’s full release

[u/Nilloc_Kcirtap → u/Mechabit_Studios]

I've been using Odin for a while now, so I sort of forgot that wasnt a native feature. It's mind boggling that it took them this long to implement it.

[u/QuitsDoubloon87]

I love how fast these have been flying out since 6.0, feels like a whole new Unity. 

If i could ask you to pass along one cristisim, its that the new hierarchy is just to big. The text/per line space should be half that size, or be scaleable freely. Thanks!

[u/unitytechnologies → u/QuitsDoubloon87]

I shall pass that along! Thanks!

- Trey
Community Man @ Unity

[u/QuitsDoubloon87 → u/unitytechnologies]

Thank you Trey! Your effort is truly apriciated!

[u/WatchMeEatOranges]

Hot dog, native dictionary serialization will come in handy!

[u/tetryds]

It finally looks like progress is happening!

[u/antiNTT]

Is CoreCLR gonna release with Unity 7 then?

[u/RichardFine → u/antiNTT]

There's a technical preview of the CoreCLR Player for desktop platforms in 6.7, but the Editor is planned for 7.0, yes.

[u/antiNTT → u/RichardFine]

Gotcha, thanks!

[u/100radsBar → u/RichardFine]

I thought 7.0 is 6.7

[u/RichardFine → u/100radsBar]

No, 7.0 has taken the place of 6.8, not 6.7. 6.7 alpha is already out.

[u/100radsBar → u/RichardFine]

aah thanks

[u/GameplayTeam12]

new about graph toolkit?

[u/unitytechnologies → u/GameplayTeam12]

Yep! https://discussions.unity.com/t/unity-6-6-is-now-available/1735357#p-7340332-graph-toolkit-26

- Trey
Community Man

[u/GameplayTeam12 → u/unitytechnologies]

awesome! keep pushing more, I love the current package and the missing piece for me is the built in runtime without doing all the boilerplate. I hope we can get that at some point!

[u/Rlaan]

Love the new changes.

Especially happy with the UITK improvements. A lot of effects we've made ourselves in 6.0 and 6.3 but this will simplify things for the future. Also nice that UITK now has a profiler integrated in the profiler itself. And really big that may go unnoticed, but we can SetText without allocations now.

But also the general profiler changes, and editor changes. Good job. Looking forward to use this in the future.

[u/SmileLonely5470]

Wow thats actually a lot of good stuff. I wasn't expecting there to be multiple changes that are actually relevant to my project.

[u/TheDevilsAdvokaat]

Nice.. There's going to be a lot of hubbub....

Edit: wow. My project now loads from the hub and is ready to run in 7.8 seconds. And play mode is instant, no lag at all.

[u/OstrakaSystems]

Christmas has come early! I'm most interested in the serialized dictionaries and 2D lighting changes but I'll have to explore the other ones this week.

[u/unitytechnologies → u/OstrakaSystems]

- Trey
Community Man @ Unity

[u/R4G_TIME]

OMG Native Dict serialization. The only thing Unity missed along Odin Visual Designer.

[u/pararar]

New hierarchy window? Is this something that has been introduced before? Did I miss this? Does anyone have experience with it already?

[u/EntropiIThink]

Thank you Trey 🫡

[u/nvidiastock]

I know that Unity had a rough couple of years but with releases like these it's finally turning around. Thank you to all the team, I am still excited to use Unity in future projects.

[u/DanQZ]

Holy SHIT what an update!

[u/colbsatron]

No more coding custom inspectors to render dictionaries, I am shocked how long this took.

[u/imwatchingyou-_-]

!RemindMe 6 hours

[u/RemindMeBot → u/imwatchingyou-_-]

I will be messaging you in 6 hours on 2026-09-01 22:28:12 UTC to remind you of this link

1 OTHERS CLICKED THIS LINK to send a PM to also be reminded and to reduce spam.

^{Parent commenter can delete this message to hide from others.}

RemindMeBot is switching to username summons. Instead of !RemindMe 1 day, use u/RemindMeBot 1 day. More info.

---

Info	Custom	Your Reminders	Feedback

[u/kenzogamesreddit]

Nice birp is still available so i can use this version

[u/Doraz_]

sadly, the new unity versions dropped support for many old devices :/

[u/WazWaz → u/Doraz_]

Mobile devices? I've recently updated because of API requirements from Google and looking closer they were all so old it's unlikely anyone with such an old device actually buys anything, so not a market loss. It's nice to keep supporting existing players on old devices, but not at the detriment of far more new players.

[u/CrazyNegotiation1934]

Is DX12 crashing randomly fixed ?

[u/SozINh]

will unity ever have a 3D/4D terrain system? those kinds of games hold a disproportionate amount of ROI, demand, etc. Minecraft and enshrouded/ other games being so big i assumed this would be a terrain component a long time ago.. Was one of the selling points of everquest next, the method of doing so is also on github.
Its a feature thats a large bottleneck for creative maps

[u/WazWaz → u/SozINh]

The method is there, so you don't need a specific implementation in Unity. There are far too many implementation-specifics for this to be something shipped with Unity - Minecraft and Space Engineers aren't the same thing for example.

[u/NeitherManner]

Does that shader compilation thing improve urp build times?