diff --git a/src/build/compiler.rs b/src/build/compiler.rs
index 3db58db..7177206 100644
--- a/src/build/compiler.rs
+++ b/src/build/compiler.rs
@@ -396,6 +396,27 @@ async fn compile_in_docker(
             cmd.arg("-e").arg(format!("CFLAGS_x86_64_pc_windows_msvc={cflags}"));
             cmd.arg("-e").arg(format!("CXXFLAGS_x86_64_pc_windows_msvc={cflags}"));
         }
+        Some("linux-arm64") | Some("linux-aarch64") => {
+            // aarch64 Linux cross-compile from an x86_64 host. Point cc-rs at
+            // the GNU cross toolchain so user-project native C/C++ deps build
+            // for aarch64 instead of the host. perry's own final link also uses
+            // aarch64-linux-gnu-gcc (see perry link/platform_cmd.rs), so the
+            // build container must provide the `gcc-aarch64-linux-gnu` package.
+            for cc_var in &["CC_aarch64_unknown_linux_gnu", "CC_aarch64-unknown-linux-gnu"] {
+                cmd.arg("-e").arg(format!("{cc_var}=aarch64-linux-gnu-gcc"));
+            }
+            for cxx_var in &["CXX_aarch64_unknown_linux_gnu", "CXX_aarch64-unknown-linux-gnu"] {
+                cmd.arg("-e").arg(format!("{cxx_var}=aarch64-linux-gnu-g++"));
+            }
+            for ar_var in &["AR_aarch64_unknown_linux_gnu", "AR_aarch64-unknown-linux-gnu"] {
+                cmd.arg("-e").arg(format!("{ar_var}=aarch64-linux-gnu-ar"));
+            }
+            // cargo's own linker var for the aarch64 leg (build-deps / proc-macro
+            // stay on host; only the target leg is redirected).
+            cmd.arg("-e").arg(
+                "CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER=aarch64-linux-gnu-gcc",
+            );
+        }
         _ => {}
     }
 
diff --git a/src/build/pipeline.rs b/src/build/pipeline.rs
index 8f3a034..26a2aef 100644
--- a/src/build/pipeline.rs
+++ b/src/build/pipeline.rs
@@ -79,6 +79,9 @@ async fn run_pipeline(
         BuildTarget::Ios => Some("ios"),
         BuildTarget::Macos => Some("macos"),
         BuildTarget::Tvos => Some("tvos"),
+        // aarch64 Linux is a cross-compile even on a Linux host, so it must
+        // pass an explicit --target (unlike native x86_64 Linux below).
+        BuildTarget::LinuxArm64 => Some("linux-arm64"),
         BuildTarget::Linux => None, // native compilation on Linux host
     };
     // For ios-game-loop: swap the runtime with the game-loop variant
@@ -140,7 +143,7 @@ async fn run_pipeline(
     }
 
     match target {
-        BuildTarget::Linux => {
+        BuildTarget::Linux | BuildTarget::LinuxArm64 => {
             run_linux_pipeline(request, cancelled, progress, tmpdir, &actual_binary, &project_dir)
                 .await
         }
@@ -722,6 +725,7 @@ fn copy_artifact(
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 enum BuildTarget {
     Linux,
+    LinuxArm64,
     Android,
     Windows,
     Ios,
@@ -737,6 +741,9 @@ fn determine_target(targets: &[String]) -> BuildTarget {
             "ios" => return BuildTarget::Ios,
             "macos" => return BuildTarget::Macos,
             "tvos" => return BuildTarget::Tvos,
+            // aarch64 Linux: cross-compiled (the builder host is x86_64) and
+            // packaged the same as x86_64 Linux — the binary is just aarch64.
+            "linux-arm64" | "linux-aarch64" => return BuildTarget::LinuxArm64,
             _ => {}
         }
     }
diff --git a/src/worker.rs b/src/worker.rs
index 6f47ec9..46fc49a 100644
--- a/src/worker.rs
+++ b/src/worker.rs
@@ -543,7 +543,7 @@ async fn connect_and_run(config: &WorkerConfig) -> Result<(), String> {
     // Send worker_hello
     let perry_version = get_perry_version(&config.perry_binary);
     let hello = WorkerMessage::WorkerHello {
-        capabilities: vec!["linux".into(), "android".into(), "windows".into(), "ios".into(), "macos".into(), "tvos".into()],
+        capabilities: vec!["linux".into(), "linux-arm64".into(), "android".into(), "windows".into(), "ios".into(), "macos".into(), "tvos".into(), "watchos".into()],
         name: config.worker_name.clone().unwrap_or_else(|| {
             hostname::get()
                 .map(|h| h.to_string_lossy().to_string())
@@ -823,6 +823,7 @@ async fn handle_build(
                 // re-queued for signing — the unsigned .app was returned as a
                 // "final" artifact and never reached TestFlight.
                 "tvos" => "ios-precompiled",
+                "watchos" => "ios-precompiled",
                 "macos" => "macos-precompiled",
                 other => other,
             };
@@ -862,6 +863,8 @@ async fn handle_build(
                     "windows" => Some("windows"),
                     "ios" => Some("ios"),
                     "macos" => Some("macos"),
+                    "tvos" => Some("tvos"),
+                    "watchos" => Some("watchos"),
                     _ => None,
                 },
                 "artifacts": [{"name": artifact_name, "size": size, "sha256": sha256}]