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OpenCode V2 breaks compatibility with older CPUs — performance and stability should come first #59756
Description
Description
Hi,
I just updated OpenCode from version 1.9 to version 2.0. Version 1.9 worked perfectly fine on my work computer, but version 2.0 won't even launch because my CPU doesn't support SSE4.2.
The error clearly states that the server process exits because Bun requires SSE4.2 support. This is a serious compatibility regression. An application that worked perfectly fine before an update has suddenly become completely unusable on the same hardware.
I understand that software evolves and dependencies change, but dropping support for older CPUs through a runtime requirement is a significant trade-off that deserves consideration. Not everyone can or wants to upgrade their hardware just to keep using a development tool.
Please stop prioritizing unnecessary changes over reliability and compatibility. We don't need a prettier OpenCode or endless UI/UX changes. We need a fast, stable, dependable tool that does its job.
I'm not claiming that the new UI is responsible for this issue. The error points directly to Bun's SSE4.2 requirement, and that's what needs to be addressed. Please investigate whether it's possible to provide a compatible build, use a runtime that supports older CPUs, or otherwise preserve compatibility with hardware that worked with version 1.9.
A development tool should not become unusable overnight simply because its underlying runtime changed.
Here is the full error:
Error: Desktop IPC handler failed
at Hee (oc://renderer/assets/main-Cs-Uxtxi.js:2:41483)
at Vee (oc://renderer/assets/main-Cs-Uxtxi.js:2:41149)
at MessagePort. (oc://renderer/assets/main-Cs-Uxtxi.js:2:39864)
Caused by:
{
"name": "UnknownError",
"message": "An error occurred in Effect.tryPromise",
"cause": {
"name": "Error",
"message": "Server process exited with code 134
error: this CPU is missing SSE4.2 support, which Bun requires.
If this is a VM, enable host CPU passthrough (e.g. -cpu host for QEMU/KVM)."
}
}
Please consider restoring compatibility with older hardware or offering an alternative build. Performance, stability, and accessibility should be priorities — not just keeping up with new dependencies and interface changes.
Plugins
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Steps to reproduce
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Activity
opencodejr commentedon Oct 27, 2026
Thanks for the report and for including the full error. I think this is a duplicate of #59461, which reports the same
Server process exited with code 134/this CPU is missing SSE4.2 support, which Bun requireserror with the v2 desktop app after upgrading from 1.x.Some background: the crash comes from the Bun runtime, not OpenCode's own code. OpenCode already ships Bun's most compatible "baseline" x64 build, but even that build needs SSE4.2/POPCNT (x86-64-v2). Supporting CPUs older than that would need a different runtime or a separately built one. #59461 is tracking that request.
Possible duplicates and related issues, ordered by likelihood:
Desktop IPC handler failedstartup failure on an older CPU, shown asterminated by SIGILLIf you can, please add your CPU model and operating system to #59461 so maintainers can see how many people this affects.
The bot will close this issue as a duplicate in 1 day unless you reply explaining how your problem is different.
opencodejr commentedon Oct 28, 2026
We haven't heard back, so I'm closing this as a duplicate of #59461. That issue tracks the same problem: v2 Desktop exits at startup with code 134 because Bun requires SSE4.2.
To help maintainers see how many people this affects, please add your CPU model and operating system to #59461. Until there is an official build, the community source build linked in #59582 may help on some CPUs that lack SSE4.2. It is not an official build and hasn't been tested with the desktop app.
If your problem turns out to be different, reply here and we can reopen this. Thanks for the report.