Gleam Language Server crash on Visual Studio Code open

[ocapmycap]

Upon opening VS Code I get this error:

The Gleam Language Server server crashed 5 times in the last 3 minutes. The server will not be restarted. See the output for more information.

And this is the output for more information: Pastebin

And the version of VS Code I'm using, if that helps:

Version: 1.108.1 (Universal)
Commit: 585eba7c0c34fd6b30faac7c62a42050bfbc0086
Date: 2026-01-14T14:55:44.241Z
Electron: 39.2.7
ElectronBuildId: 12953945
Chromium: 142.0.7444.235
Node.js: 22.21.1
V8: 14.2.231.21-electron.0
OS: Darwin arm64 24.6.0

[seafoamteal]

Hi! Is there any chance you can share the code you were working on, or a minimal reproduction that causes the same crash? Thanks!

[lpil]

From the error it looks like a problem with the compiler rather than the LS.

Once we have the code that produces the crash we can investigate 👍

[ocapmycap]

Hi! This is a pretty big project and I was jumping about. I cannot remember precisely what I was working on when I first started seeing (and ignoring) the error, but here is the tomfool thing I just reverted and stopped seeing the crash:

I had my Lustre model in the top level of my client/src/. I wanted to refactor it. I created a module named model/v2 and created a file named model.gleam that contained a pub type Model. To illustrate (simplified):

.
└── src
    ├── model_v2
    │   └── model.gleam
    └── model.gleam

3 directories, 2 files

I reread the compiler crash message -- "Panic: compiler-core/src/type_/expression.rs:3435
Field exists
Gleam version: 1.14.0
Operating system: macos"
The "field exists" part made me thin it was this shadowing. When I changed the name of this file to model_v2.gleam, I stopped getting the crashes.

.
└── src
    ├── model_v2
    │   └── model_v2.gleam
    └── model.gleam

3 directories, 2 files

However, I don't see the crashes in the minimal example above.

[lpil]

Please share the code you had when the error occurred, we are not able to debug with only file names 🙏

[ocapmycap]

But the idea of sharing this code in its current state provokes every anxiety I have! 😅I will provide when I get a chance.

…

On Sun, Jan 18, 2026, 11:04 AM Louis Pilfold ***@***.***> wrote: *lpil* left a comment (gleam-lang/gleam#5296) <#5296 (comment)> Please share the code you had when the error occurred, we are not able to debug with only file names 🙏 — Reply to this email directly, view it on GitHub <#5296 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ADT36I4SWU6UYLAV2YIDRIT4HKWXVAVCNFSM6AAAAACR75UAEWVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTONRUGM4TIMJUGE> . You are receiving this because you authored the thread.Message ID: ***@***.***>