diff --git a/src/ast.rs b/src/ast.rs
index f4bc7310..5e99c454 100644
--- a/src/ast.rs
+++ b/src/ast.rs
@@ -505,9 +505,7 @@ impl Book {
     }
     let mut book = hvm::Book { defs: Vec::new() };
     for (fid, name) in &fid_to_name {
-      let Some(ast_def) = self.defs.get(name) else {
-        panic!("missing `@main` definition");
-      };
+      let ast_def = self.defs.get(name).expect("missing `@main` definition");
       let mut def = hvm::Def {
         name: name.clone(),
         safe: true,
diff --git a/tests/snapshots/run__file@empty.hvm.snap b/tests/snapshots/run__file@empty.hvm.snap
index c2ad3ff0..b5b4735e 100644
--- a/tests/snapshots/run__file@empty.hvm.snap
+++ b/tests/snapshots/run__file@empty.hvm.snap
@@ -4,6 +4,6 @@ expression: rust_output
 input_file: tests/programs/empty.hvm
 ---
 exit status: 101
-thread 'main' panicked at src/ast.rs:509:9:
+thread 'main' panicked at src/ast.rs:508:41:
 missing `@main` definition
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace