This issue exists since at least v8.4.2 (the oldest version available in the playground). The following code triggers error `File "compiler/core/lam_compile_external_call.ml", line 424, characters 11-17: Assertion failed`: ```rescript @get external foo: unit => string = "foo" let x = foo() ``` [Playground link](https://rescript-lang.org/try?version=v12.0.0-beta.2&module=esmodule&code=AIcwpgLgUGAeFgE4DsCGAbABAMwPa4C5MBXZASwkwF4A+TAZwkTORGswCI9cOop1ImWO24AKAJRA) Relevant compiler code: https://github.com/rescript-lang/rescript/blob/ac6a87d2bec19c37e23f57705e8ea5e5ecdf240c/compiler/core/lam_compile_external_call.ml#L416-L424 Not calling `foo` compiles fine though: ```rescript @get external foo: unit => string = "foo" ```