diff --git a/src/build.rs b/src/build.rs
index 345f403..4d97057 100644
--- a/src/build.rs
+++ b/src/build.rs
@@ -11,6 +11,7 @@ pub mod read_compile_state;
 use crate::build::compile::{mark_modules_with_deleted_deps_dirty, mark_modules_with_expired_deps_dirty};
 use crate::helpers::emojis::*;
 use crate::helpers::{self, get_workspace_root};
+use crate::sourcedirs;
 use ahash::AHashSet;
 use build_types::*;
 use console::style;
@@ -344,6 +345,7 @@ pub fn incremental_build(
     let compile_duration = start_compiling.elapsed();
 
     logs::finalize(&build_state.packages);
+    sourcedirs::print(&build_state);
     pb.finish();
     if !compile_errors.is_empty() {
         if helpers::contains_ascii_characters(&compile_warnings) {
diff --git a/src/lib.rs b/src/lib.rs
index e35ee28..b84aed0 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -4,4 +4,5 @@ pub mod cmd;
 pub mod helpers;
 pub mod lock;
 pub mod queue;
+pub mod sourcedirs;
 pub mod watcher;
diff --git a/src/main.rs b/src/main.rs
index 5001219..30a9f73 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,13 +1,7 @@
 use clap::{Parser, ValueEnum};
 use regex::Regex;
 
-pub mod bsconfig;
-pub mod build;
-pub mod cmd;
-pub mod helpers;
-pub mod lock;
-pub mod queue;
-pub mod watcher;
+use rewatch::{build, cmd, lock, watcher};
 
 #[derive(Debug, Clone, ValueEnum)]
 enum Command {
diff --git a/src/sourcedirs.rs b/src/sourcedirs.rs
new file mode 100644
index 0000000..cf452bf
--- /dev/null
+++ b/src/sourcedirs.rs
@@ -0,0 +1,117 @@
+use crate::build::build_types::BuildState;
+use crate::build::packages::Package;
+use ahash::{AHashMap, AHashSet};
+use rayon::prelude::*;
+use serde::Serialize;
+use serde_json::json;
+use std::fs::File;
+use std::io::prelude::*;
+
+type Dir = String;
+type PackageName = String;
+type AbsolutePath = String;
+type PackagePath = String;
+
+#[derive(Serialize, Debug, Clone, PartialEq, Hash)]
+pub struct SourceDirs {
+    pub dirs: Vec<Dir>,
+    pub pkgs: Vec<(PackageName, AbsolutePath)>,
+    pub generated: Vec<String>,
+}
+
+pub fn print(buildstate: &BuildState) {
+    let (_name, package) = buildstate
+        .packages
+        .iter()
+        .find(|(_name, package)| package.is_root)
+        .expect("Could not find root package");
+
+    // First do all child packages
+    let child_packages = buildstate
+        .packages
+        .par_iter()
+        .filter(|(_name, package)| !package.is_root)
+        .map(|(_name, package)| {
+            let path = package.get_bs_build_path();
+
+            let dirs = package
+                .dirs
+                .to_owned()
+                .unwrap_or(AHashSet::new())
+                .iter()
+                .filter_map(|path| path.to_str().map(|x| x.to_string()))
+                .collect::<AHashSet<String>>();
+
+            fn deps_to_pkgs<'a>(
+                packages: &'a AHashMap<String, Package>,
+                xs: &'a Option<Vec<String>>,
+            ) -> AHashSet<(String, PackagePath)> {
+                xs.as_ref()
+                    .unwrap_or(&vec![])
+                    .iter()
+                    .filter_map(|name| {
+                        packages
+                            .get(&name.to_owned())
+                            .map(|package| (name.clone(), package.path.clone()))
+                    })
+                    .collect::<AHashSet<(String, PackagePath)>>()
+            }
+
+            let pinned_dependencies =
+                deps_to_pkgs(&buildstate.packages, &package.bsconfig.pinned_dependencies);
+            let bs_dependencies = deps_to_pkgs(&buildstate.packages, &package.bsconfig.bs_dependencies);
+            let bs_dev_dependencies =
+                deps_to_pkgs(&buildstate.packages, &package.bsconfig.bs_dev_dependencies);
+
+            let mut pkgs = AHashMap::new();
+            pkgs.extend(pinned_dependencies);
+            pkgs.extend(bs_dependencies);
+            pkgs.extend(bs_dev_dependencies);
+
+            let name = path + "/.sourcedirs.json";
+            let _ = File::create(&name).map(|mut file| {
+                let source_files = SourceDirs {
+                    dirs: dirs.clone().into_iter().collect::<Vec<Dir>>(),
+                    pkgs: pkgs
+                        .clone()
+                        .into_iter()
+                        .collect::<Vec<(PackageName, AbsolutePath)>>(),
+                    generated: vec![],
+                };
+
+                file.write(json!(source_files).to_string().as_bytes())
+            });
+            let _ = std::fs::copy(package.get_bs_build_path(), package.get_build_path());
+
+            (&package.path, dirs, pkgs)
+        })
+        .collect::<Vec<(
+            &PackagePath,
+            AHashSet<String>,
+            AHashMap<PackageName, AbsolutePath>,
+        )>>();
+
+    let mut all_dirs = AHashSet::new();
+    let mut all_pkgs: AHashMap<PackageName, AbsolutePath> = AHashMap::new();
+
+    child_packages.iter().for_each(|(package_path, dirs, pkgs)| {
+        dirs.iter().for_each(|dir| {
+            all_dirs.insert(format!("{package_path}/{dir}"));
+        });
+
+        all_pkgs.extend(pkgs.to_owned());
+    });
+
+    let path = package.get_bs_build_path();
+    let name = path + "/.sourcedirs.json";
+    let _ = File::create(name.clone()).map(|mut file| {
+        let all_source_files = SourceDirs {
+            dirs: all_dirs.into_iter().collect::<Vec<String>>(),
+            pkgs: all_pkgs.into_iter().collect::<Vec<(PackageName, AbsolutePath)>>(),
+            generated: vec![],
+        };
+        file.write(json!(all_source_files).to_string().as_bytes())
+    });
+
+    let _ = std::fs::copy(package.get_bs_build_path(), package.get_build_path());
+}