The situation:
Generating a TypeScript client for my Encore API crashed the compiler with Internal compiler error [E0001]: An unhandled panic occurred in the Encore compiler: runtime error: invalid memory address or nil pointer dereference. A minimal repro showed it only happens when you use an inline type in an api definition, that inline type references a named type, AND the service folder name doesnt match the service name. The maintainer confirmed the fix version in January 2026.
What actually fixes it (verified in the thread):
This was a compiler bug in Encore's client generation, triggered by that specific combination of an inline type referencing a named type with a mismatched service/folder name. Its fixed in encore v1.53.7, so run encore version update and regenerate. The workaround if youre stuck on an older version is to not use the inline type: define the full request type as a named type before the api definition, which one reporter confirmed avoids the panic.