make eval configurable, add help text to cli args

src/config.rs

@@ -1,9 +1,28 @@
 #[derive(clap::Parser, Debug)]
 pub struct Options {
     #[arg(long = "system", short)]
+    /// list of systems to build for
     pub systems: Vec<String>,
+
+    #[arg(long, default_value = ".#checks")]
+    /// flake ref to evaluate for jobs
+    pub flake_path: String,
+
     #[arg(long)]
+    /// whether to check the cache status for derivations
+    ///
+    /// if true, cached derivations will not be built
     pub check_cached: bool,
+
     #[arg(long)]
+    /// store uri where build outputs will be uploaded to
     pub copy_to: Option<String>,
+
+    #[arg(long, default_value = "4")]
+    /// maximum number of evaluation workers
+    pub eval_workers: u8,
+
+    #[arg(long, default_value = "4096")]
+    /// maximum allowed amount of memory in mib per eval worker
+    pub eval_worker_memory: u32,
 }

src/eval.rs

@@ -16,15 +16,14 @@ pub async fn nix_eval_jobs(
     result_tx: Sender<NixCiResult>,
 ) -> anyhow::Result<()> {
     let mut command = Command::new("nix-eval-jobs");
-    // TODO: make this configurable
     command.args(&[
         "--force-recurse",
         "--max-memory-size",
-        "3072",
+        format!("{}", opts.eval_worker_memory).as_str(),
         "--workers",
-        "4",
+        format!("{}", opts.eval_workers).as_str(),
         "--flake",
-        ".#checks",
+        opts.flake_path.as_str(),
     ]);
     if opts.check_cached {
         command.arg("--check-cache-status");