diff --git a/src/main.rs b/src/main.rs
index e0789db..76bfae3 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,3 +1,5 @@
+use std::fs;
+
 use clap::{Args, Parser, Subcommand};
 use color_eyre::eyre::Result;
 use reqwest::Client;
@@ -13,6 +15,14 @@ struct Cli {
 #[derive(Subcommand)]
 enum CliCommands {
     Track(Track),
+    GetDiff(GetDiff),
+}
+
+#[derive(Args, Debug, Default)]
+struct GetDiff {
+    pr: String,
+    #[arg(long, default_value_t = ("./patches/PR".to_string()))]
+    path: String,
 }
 
 #[derive(Args, Debug, Default)]
@@ -31,8 +41,10 @@ const BRANCHES: &[&str] = &[
 struct PR {
     title: String,
     state: String,
+    merged: bool,
     merged_at: Option<String>,
     merge_commit_sha: String,
+    mergeable: bool,
 }
 
 #[derive(Debug, Deserialize)]
@@ -65,6 +77,14 @@ async fn contains(branch: &str, pr: &PR, client: &Client) -> Result<bool> {
     }
     Ok(false)
 }
+async fn get_diff(pr: &str, path: &str, client: &Client) -> Result<()> {
+    let req = client
+        .get(format!("https://github.com/nixos/nixpkgs/pull/{}.diff", pr))
+        .send();
+    let text = &req.await?.text().await?;
+    fs::write(format!("{}/{}.diff", path, pr), text)?;
+    Ok(())
+}
 
 #[tokio::main]
 async fn main() -> Result<()> {
@@ -78,6 +98,9 @@ async fn main() -> Result<()> {
                 println!("{}: {}", i, contains(i, &pr, &client).await?);
             }
         }
+        CliCommands::GetDiff(opts) => {
+            get_diff(&opts.pr, &opts.path, &client).await?;
+        }
     };
     Ok(())
 }