Add ability to build nix derivations

Signed-off-by: Marcel Müller <neikos@neikos.email>

nixie-cli/src/main.rs

@@ -0,0 +1,53 @@
+use clap::Parser;
+use clap::Subcommand;
+use nixie_build::NixBackend;
+use nixie_build::NixBuilder;
+use nixie_build::NixCliBackend;
+
+#[derive(Debug, Parser)]
+#[command(version, about)]
+struct Args {
+    #[clap(subcommand)]
+    command: ArgCommand,
+}
+
+#[derive(Debug, Subcommand)]
+enum ArgCommand {
+    Build { installable: String },
+}
+
+#[tokio::main]
+async fn main() -> anyhow::Result<()> {
+    let args = Args::parse();
+
+    run(args).await
+}
+
+async fn run(args: Args) -> anyhow::Result<()> {
+    match args.command {
+        ArgCommand::Build { installable } => {
+            build_and_report(NixCliBackend::new("nix".to_string()), installable).await?;
+        }
+    }
+
+    Ok(())
+}
+
+async fn build_and_report<B: NixBackend>(backend: B, installable: String) -> anyhow::Result<()> {
+    let builder = NixBuilder::new(backend);
+
+    let build_result = builder.build(installable).await?;
+
+    for (drv, result) in build_result {
+        println!(
+            "Built:\t{drv}: {}",
+            if result.success() {
+                "Succesfully"
+            } else {
+                "Errored"
+            }
+        )
+    }
+
+    Ok(())
+}