diff --git a/tools/rust_analyzer/lib.rs b/tools/rust_analyzer/lib.rs
new file mode 100644
index 0000000..68db7e0
--- /dev/null
+++ b/tools/rust_analyzer/lib.rs
@@ -0,0 +1,79 @@
+use std::path::Path;
+use std::process::Command;
+
+use anyhow::anyhow;
+use runfiles::Runfiles;
+
+mod aquery;
+mod rust_project;
+
+const SYSROOT_SRC_FILE_RUNFILES_PREFIX: &str = "rules_rust";
+
+pub fn generate_crate_info(
+    bazel: impl AsRef<Path>,
+    workspace: impl AsRef<Path>,
+    rules_rust: impl AsRef<str>,
+    targets: &[String],
+) -> anyhow::Result<()> {
+    log::debug!("Building rust_analyzer_crate_spec files for {:?}", targets);
+
+    let output = Command::new(bazel.as_ref())
+        .current_dir(workspace.as_ref())
+        .arg("build")
+        .arg(format!(
+            "--aspects={}//rust:defs.bzl%rust_analyzer_aspect",
+            rules_rust.as_ref()
+        ))
+        .arg("--output_groups=rust_analyzer_crate_spec")
+        .args(targets)
+        .output()?;
+
+    if !output.status.success() {
+        return Err(anyhow!(
+            "bazel build failed:({})\n{}",
+            output.status,
+            String::from_utf8_lossy(&output.stderr)
+        ));
+    }
+
+    Ok(())
+}
+
+pub fn write_rust_project(
+    bazel: impl AsRef<Path>,
+    workspace: impl AsRef<Path>,
+    rules_rust_name: &impl AsRef<str>,
+    targets: &[String],
+    execution_root: impl AsRef<Path>,
+    rust_project_path: impl AsRef<Path>,
+) -> anyhow::Result<()> {
+    let crate_specs = aquery::get_crate_specs(
+        bazel.as_ref(),
+        workspace.as_ref(),
+        execution_root.as_ref(),
+        targets,
+        rules_rust_name.as_ref(),
+    )?;
+
+    let workspace_name = match rules_rust_name.as_ref().trim_start_matches('@') {
+        "" => SYSROOT_SRC_FILE_RUNFILES_PREFIX,
+        s => s,
+    };
+    let sysroot_path = format!(
+        "{}/rust/private/rust_analyzer_detect_sysroot.rust_analyzer_sysroot_src",
+        workspace_name
+    );
+    let r = Runfiles::create()?;
+    let path = r.rlocation(sysroot_path);
+    let sysroot_src = std::fs::read_to_string(&path)?;
+
+    let rust_project = rust_project::generate_rust_project(&sysroot_src, &crate_specs)?;
+
+    rust_project::write_rust_project(
+        rust_project_path.as_ref(),
+        execution_root.as_ref(),
+        &rust_project,
+    )?;
+
+    Ok(())
+}