diff --git a/build.rs b/build.rs
index 6998d60a4..5a9ce3cd5 100644
--- a/build.rs
+++ b/build.rs
@@ -6,6 +6,8 @@ use std::io::Write;
 use std::path::Path;
 
 pub fn main() {
+    // println!("cargo:warning=Running build.rs");
+
     if let Ok(profile) = env::var("PROFILE") {
         println!("cargo:rustc-cfg=build={:?}", profile);
     }
@@ -15,6 +17,11 @@ pub fn main() {
     let override_prefix: &str = "uu_";
 
     let out_dir = env::var("OUT_DIR").unwrap();
+    // println!("cargo:warning=out_dir={}", out_dir);
+    let manifest_dir = env::var("CARGO_MANIFEST_DIR").unwrap().replace("\\", "/");
+    // println!("cargo:warning=manifest_dir={}", manifest_dir);
+    let util_tests_dir = format!("{}/tests/by-util", manifest_dir);
+    // println!("cargo:warning=util_tests_dir={}", util_tests_dir);
 
     let mut crates = Vec::new();
     for (key, val) in env::vars() {
@@ -33,6 +40,7 @@ pub fn main() {
     crates.sort();
 
     let mut mf = File::create(Path::new(&out_dir).join("uutils_map.rs")).unwrap();
+    let mut tf = File::create(Path::new(&out_dir).join("test_modules.rs")).unwrap();
 
     mf.write_all(
         "type UtilityMap = HashMap<&'static str, fn(Vec<String>) -> i32>;\n\
@@ -46,8 +54,8 @@ pub fn main() {
 
     for krate in crates {
         match krate.as_ref() {
-            k if k.starts_with(override_prefix) => mf
-                .write_all(
+            k if k.starts_with(override_prefix) => {
+                mf.write_all(
                     format!(
                         "\tmap.insert(\"{k}\", {krate}::uumain);\n",
                         k = krate[override_prefix.len()..].to_string(),
@@ -55,18 +63,38 @@ pub fn main() {
                     )
                     .as_bytes(),
                 )
-                .unwrap(),
-            "false" | "true" => mf
-                .write_all(
+                .unwrap();
+                tf.write_all(
+                    format!(
+                        "#[path=\"{dir}/test_{k}.rs\"]\nmod test_{k};\n",
+                        k = krate[override_prefix.len()..].to_string(),
+                        dir = util_tests_dir,
+                    )
+                    .as_bytes(),
+                )
+                .unwrap()
+            }
+            "false" | "true" => {
+                mf.write_all(
                     format!(
                         "\tmap.insert(\"{krate}\", r#{krate}::uumain);\n",
                         krate = krate
                     )
                     .as_bytes(),
                 )
-                .unwrap(),
-            "hashsum" => mf
-                .write_all(
+                .unwrap();
+                tf.write_all(
+                    format!(
+                        "#[path=\"{dir}/test_{krate}.rs\"]\nmod test_{krate};\n",
+                        krate = krate,
+                        dir = util_tests_dir,
+                    )
+                    .as_bytes(),
+                )
+                .unwrap()
+            }
+            "hashsum" => {
+                mf.write_all(
                     format!(
                         "\
                         \tmap.insert(\"{krate}\", {krate}::uumain);\n\
@@ -88,20 +116,41 @@ pub fn main() {
                     )
                     .as_bytes(),
                 )
-                .unwrap(),
-            _ => mf
-                .write_all(
+                .unwrap();
+                tf.write_all(
+                    format!(
+                        "#[path=\"{dir}/test_{krate}.rs\"]\nmod test_{krate};\n",
+                        krate = krate,
+                        dir = util_tests_dir,
+                    )
+                    .as_bytes(),
+                )
+                .unwrap()
+            }
+            _ => {
+                mf.write_all(
                     format!(
                         "\tmap.insert(\"{krate}\", {krate}::uumain);\n",
                         krate = krate
                     )
                     .as_bytes(),
                 )
-                .unwrap(),
+                .unwrap();
+                tf.write_all(
+                    format!(
+                        "#[path=\"{dir}/test_{krate}.rs\"]\nmod test_{krate};\n",
+                        krate = krate,
+                        dir = util_tests_dir,
+                    )
+                    .as_bytes(),
+                )
+                .unwrap()
+            }
         }
     }
 
     mf.write_all(b"map\n}\n").unwrap();
 
     mf.flush().unwrap();
+    tf.flush().unwrap();
 }