diff --git a/compiler/load/build.rs b/compiler/load/build.rs
new file mode 100644
index 0000000000..a3c39c1c91
--- /dev/null
+++ b/compiler/load/build.rs
@@ -0,0 +1,53 @@
+use std::path::PathBuf;
+
+use bumpalo::Bump;
+use roc_module::symbol::ModuleId;
+
+const MODULES: &[(ModuleId, &str)] = &[
+    (ModuleId::BOOL, "Bool.roc"),
+    //    (ModuleId::RESULT, "Result.roc"),
+    //    (ModuleId::LIST, "List.roc"),
+    //    (ModuleId::STR, "Str.roc"),
+    //    (ModuleId::DICT, "Dict.roc"),
+    //    (ModuleId::SET, "Set.roc"),
+    //    (ModuleId::BOX, "Box.roc"),
+    //    (ModuleId::NUM, "Num.roc"),
+];
+
+fn main() {
+    for (module_id, filename) in MODULES {
+        write_subs_for_module(*module_id, filename);
+    }
+}
+
+fn write_subs_for_module(module_id: ModuleId, filename: &str) {
+    // Tell Cargo that if the given file changes, to rerun this build script.
+    println!(
+        "cargo:rerun-if-changed=../builtins/standard_library/{}",
+        filename
+    );
+
+    let arena = Bump::new();
+    let src_dir = PathBuf::from(".");
+    let source = roc_builtins::standard_library::module_source(module_id);
+    let target_info = roc_target::TargetInfo::default_x86_64();
+
+    let res_module = roc_load_internal::file::load_and_typecheck_str(
+        &arena,
+        PathBuf::from(filename),
+        source,
+        &src_dir,
+        Default::default(),
+        target_info,
+    );
+
+    let module = res_module.unwrap();
+    let subs = module.solved.inner();
+    let exposed_vars_by_symbol: Vec<_> = module.exposed_to_host.into_iter().collect();
+
+    let mut output_path = PathBuf::from(std::env::var("OUT_DIR").unwrap());
+    output_path.extend(&[filename]);
+    output_path.set_extension("dat");
+    let mut file = std::fs::File::create(&output_path).unwrap();
+    subs.serialize(&exposed_vars_by_symbol, &mut file).unwrap();
+}
diff --git a/compiler/load/src/lib.rs b/compiler/load/src/lib.rs
index be7ba56d20..3b05a22bdf 100644
--- a/compiler/load/src/lib.rs
+++ b/compiler/load/src/lib.rs
@@ -32,22 +32,6 @@ fn load<'a>(
     )
 }
 
-const BOOL: &[u8] = include_bytes!(concat!(env!("OUT_DIR"), "/Bool.dat")) as &[_];
-
-fn deserialize_help(bytes: &[u8]) -> (Subs, Vec<(Symbol, Variable)>) {
-    let (subs, slice) = Subs::deserialize(bytes);
-
-    (subs, slice.to_vec())
-}
-
-fn read_cached_subs() -> MutMap<ModuleId, (Subs, Vec<(Symbol, Variable)>)> {
-    let mut output = MutMap::default();
-
-    output.insert(ModuleId::BOOL, deserialize_help(BOOL));
-
-    output
-}
-
 pub fn load_and_monomorphize_from_str<'a>(
     arena: &'a Bump,
     filename: PathBuf,
@@ -120,3 +104,33 @@ pub fn load_and_typecheck<'a>(
         TypeChecked(module) => Ok(module),
     }
 }
+
+const BOOL: &[u8] = include_bytes!(concat!(env!("OUT_DIR"), "/Bool.dat")) as &[_];
+// const RESULT: &[u8] = include_bytes!(concat!(env!("OUT_DIR"), "/Result.dat")) as &[_];
+// const LIST: &[u8] = include_bytes!(concat!(env!("OUT_DIR"), "/List.dat")) as &[_];
+// const STR: &[u8] = include_bytes!(concat!(env!("OUT_DIR"), "/Str.dat")) as &[_];
+// const DICT: &[u8] = include_bytes!(concat!(env!("OUT_DIR"), "/Dict.dat")) as &[_];
+// const SET: &[u8] = include_bytes!(concat!(env!("OUT_DIR"), "/Set.dat")) as &[_];
+// const BOX: &[u8] = include_bytes!(concat!(env!("OUT_DIR"), "/Box.dat")) as &[_];
+// const NUM: &[u8] = include_bytes!(concat!(env!("OUT_DIR"), "/Num.dat")) as &[_];
+
+fn deserialize_help(bytes: &[u8]) -> (Subs, Vec<(Symbol, Variable)>) {
+    let (subs, slice) = Subs::deserialize(bytes);
+
+    (subs, slice.to_vec())
+}
+
+fn read_cached_subs() -> MutMap<ModuleId, (Subs, Vec<(Symbol, Variable)>)> {
+    let mut output = MutMap::default();
+
+    output.insert(ModuleId::BOOL, deserialize_help(BOOL));
+    // output.insert(ModuleId::RESULT, deserialize_help(RESULT));
+    // output.insert(ModuleId::LIST, deserialize_help(LIST));
+    // output.insert(ModuleId::STR, deserialize_help(STR));
+    // output.insert(ModuleId::DICT, deserialize_help(DICT));
+    // output.insert(ModuleId::SET, deserialize_help(SET));
+    // output.insert(ModuleId::BOX, deserialize_help(BOX));
+    // output.insert(ModuleId::NUM, deserialize_help(NUM));
+
+    output
+}
diff --git a/compiler/load_internal/src/file.rs b/compiler/load_internal/src/file.rs
index a4e756a202..f5514a6749 100644
--- a/compiler/load_internal/src/file.rs
+++ b/compiler/load_internal/src/file.rs
@@ -3171,8 +3171,6 @@ fn run_solve<'a>(
         .filter(|(k, _)| exposed_symbols.contains(k))
         .collect();
 
-    dbg!(&exposed_vars_by_symbol);
-
     let mut solved_subs = solved_subs;
     let (storage_subs, stored_vars_by_symbol) =
         roc_solve::module::exposed_types_storage_subs(&mut solved_subs, &exposed_vars_by_symbol);