diff --git a/lib/src/wasm/builder.rs b/lib/src/wasm/builder.rs
index 551caec01..4e809172f 100644
--- a/lib/src/wasm/builder.rs
+++ b/lib/src/wasm/builder.rs
@@ -344,6 +344,15 @@ impl WasmModuleBuilder {
             self.main_func.finish(Vec::new(), &mut self.module.funcs);
 
         self.module.exports.add("main", main_func);
+
+        // WasmModuleBuilder::new adds to the WASM module all the functions
+        // that are labeled as #[wasm_export] or #[module_export]. However,
+        // not all the functions are used in the final WASM code because
+        // (ie: some YARA modules are not imported by the rules). This removes
+        // the functions that are not actually used, reducing the size of the
+        // compiled rules.
+        walrus::passes::gc::run(&mut self.module);
+
         self.module
     }
 }