diff --git a/crates/fj-proc/src/lib.rs b/crates/fj-proc/src/lib.rs
index fceb173cd..6432a25b0 100644
--- a/crates/fj-proc/src/lib.rs
+++ b/crates/fj-proc/src/lib.rs
@@ -63,7 +63,9 @@ pub fn model(_: TokenStream, input: TokenStream) -> TokenStream {
 
     let function_boilerplate = quote! {
         #[no_mangle]
-            pub extern "C" fn model(args: &HashMap<String, String>) -> fj::Shape
+            pub extern "C" fn model(
+                args: &std::collections::HashMap<String, String>
+            ) -> fj::Shape
     };
 
     quote! {
diff --git a/models/cuboid/src/lib.rs b/models/cuboid/src/lib.rs
index 59a09995f..6ce903ae5 100644
--- a/models/cuboid/src/lib.rs
+++ b/models/cuboid/src/lib.rs
@@ -1,5 +1,3 @@
-use std::collections::HashMap;
-
 #[fj::model]
 pub fn model(
     #[value(default = 3.0)] x: f64,
diff --git a/models/spacer/src/lib.rs b/models/spacer/src/lib.rs
index 7cb687eb8..385ad5328 100644
--- a/models/spacer/src/lib.rs
+++ b/models/spacer/src/lib.rs
@@ -1,5 +1,3 @@
-use std::collections::HashMap;
-
 use fj::syntax::*;
 
 #[fj::model]
diff --git a/models/star/src/lib.rs b/models/star/src/lib.rs
index e8e29d2aa..b8af50107 100644
--- a/models/star/src/lib.rs
+++ b/models/star/src/lib.rs
@@ -1,5 +1,5 @@
 use fj::Angle;
-use std::{collections::HashMap, f64::consts::PI};
+use std::f64::consts::PI;
 extern crate fj;
 
 #[fj::model]
diff --git a/models/test/src/lib.rs b/models/test/src/lib.rs
index cf4ce09c2..c35fa16af 100644
--- a/models/test/src/lib.rs
+++ b/models/test/src/lib.rs
@@ -1,4 +1,4 @@
-use std::{collections::HashMap, f64::consts::PI};
+use std::f64::consts::PI;
 
 use fj::{syntax::*, Angle};