diff --git a/crates/notgraph/src/main.rs b/crates/notgraph/src/main.rs
index 7f7732e..4be8a6a 100644
--- a/crates/notgraph/src/main.rs
+++ b/crates/notgraph/src/main.rs
@@ -1,3 +1,90 @@
-fn main() {
-    println!("notgraph");
+use notgraph_lib::{analysis, crate_graph, emit, module_graph, symbols};
+use anyhow::{Context, Result};
+use clap::Parser;
+use std::path::PathBuf;
+
+#[derive(Parser)]
+#[command(name = "notgraph", about = "Workspace module graph and symbol analysis")]
+struct Cli {
+    #[arg(long, default_value = "docs/graph")]
+    output: PathBuf,
+
+    #[arg(long)]
+    fail_on_cycles: bool,
+
+    #[arg(long, default_value_t = 10)]
+    top: usize,
+}
+
+fn main() -> Result<()> {
+    let cli = Cli::parse();
+    let manifest = find_workspace_manifest()?;
+    let workspace_root = manifest.parent().unwrap().to_path_buf();
+
+    let crate_g = crate_graph::build(&manifest)
+        .context("failed to build crate graph")?;
+
+    let meta = cargo_metadata::MetadataCommand::new()
+        .manifest_path(&manifest)
+        .no_deps()
+        .exec()?;
+
+    let mut module_graphs = Vec::new();
+    let mut symbol_tables = Vec::new();
+
+    for pkg in &meta.packages {
+        if !meta.workspace_members.contains(&pkg.id) {
+            continue;
+        }
+        let src_dir = PathBuf::from(pkg.manifest_path.as_str())
+            .parent().unwrap().join("src");
+        if !src_dir.exists() {
+            continue;
+        }
+        module_graphs.push(
+            module_graph::build(pkg.name.clone(), &src_dir)
+                .with_context(|| format!("module_graph failed for {}", pkg.name))?
+        );
+        symbol_tables.push(
+            symbols::build(pkg.name.clone(), &src_dir)
+                .with_context(|| format!("symbols failed for {}", pkg.name))?
+        );
+    }
+
+    let stats = analysis::analyse(&crate_g, &module_graphs, cli.top);
+
+    let output_dir = if cli.output.is_absolute() {
+        cli.output.clone()
+    } else {
+        workspace_root.join(&cli.output)
+    };
+
+    emit::write_all(&output_dir, &stats, &symbol_tables)
+        .context("failed to write reports")?;
+
+    println!("notgraph: reports written to {}", output_dir.display());
+
+    if cli.fail_on_cycles && !stats.cycles.is_empty() {
+        eprintln!("notgraph: {} cycle(s) detected", stats.cycles.len());
+        for cycle in &stats.cycles {
+            eprintln!("  {}", cycle.join(" -> "));
+        }
+        std::process::exit(1);
+    }
+
+    Ok(())
+}
+
+fn find_workspace_manifest() -> Result<PathBuf> {
+    let mut dir = std::env::current_dir()?;
+    loop {
+        let candidate = dir.join("Cargo.toml");
+        if candidate.exists() {
+            let content = std::fs::read_to_string(&candidate)?;
+            if content.contains("[workspace]") {
+                return Ok(candidate);
+            }
+        }
+        anyhow::ensure!(dir.pop(), "could not find workspace Cargo.toml");
+    }
 }
diff --git a/crates/notgraph/src/module_graph.rs b/crates/notgraph/src/module_graph.rs
index ca184c1..0d2c857 100644
--- a/crates/notgraph/src/module_graph.rs
+++ b/crates/notgraph/src/module_graph.rs
@@ -55,7 +55,7 @@ pub fn build(krate: CrateName, src_dir: &Path) -> Result<ModuleGraph> {
     for entry in WalkDir::new(src_dir)
         .into_iter()
         .filter_map(|e| e.ok())
-        .filter(|e| e.path().extension().map_or(false, |x| x == "rs"))
+        .filter(|e| e.path().extension().is_some_and(|x| x == "rs"))
     {
         let path = entry.path();
         let content = std::fs::read_to_string(path)?;
diff --git a/crates/notgraph/src/symbols.rs b/crates/notgraph/src/symbols.rs
index eb56472..7e6a833 100644
--- a/crates/notgraph/src/symbols.rs
+++ b/crates/notgraph/src/symbols.rs
@@ -64,7 +64,7 @@ pub fn build(krate: CrateName, src_dir: &Path) -> Result<SymbolTable> {
     for entry in WalkDir::new(src_dir)
         .into_iter()
         .filter_map(|e| e.ok())
-        .filter(|e| e.path().extension().map_or(false, |x| x == "rs"))
+        .filter(|e| e.path().extension().is_some_and(|x| x == "rs"))
     {
         let path = entry.path();
         let content = std::fs::read_to_string(path)?;