diff --git a/.github/workflows/ci_zig.yml b/.github/workflows/ci_zig.yml
index 80374a0891..ff97f11d7b 100644
--- a/.github/workflows/ci_zig.yml
+++ b/.github/workflows/ci_zig.yml
@@ -85,18 +85,25 @@ jobs:
         include:
           - os: macos-15-intel
             cpu_flag: -Dcpu=x86_64_v3
+            target_flag: ''
           - os: macos-15
             cpu_flag: ''
+            target_flag: ''
           - os: ubuntu-22.04
             cpu_flag: -Dcpu=x86_64_v3
+            target_flag: -Dtarget=x86_64-linux-musl
           - os: ubuntu-24.04-arm
             cpu_flag: ''
+            target_flag: -Dtarget=aarch64-linux-musl
           - os: windows-2022
             cpu_flag: -Dcpu=x86_64_v3
+            target_flag: ''
           - os: windows-2025
             cpu_flag: -Dcpu=x86_64_v3
+            target_flag: ''
           - os: windows-11-arm
             cpu_flag: ''
+            target_flag: ''
 
     steps:
       - name: Checkout
@@ -119,7 +126,7 @@ jobs:
       - name: build roc + repro executables
         uses: ./.github/actions/flaky-retry
         with:
-          command: "zig build -Dfuzz -Dsystem-afl=false -Doptimize=ReleaseFast ${{ matrix.cpu_flag }}"
+          command: "zig build -Dfuzz -Dsystem-afl=false -Doptimize=ReleaseFast ${{ matrix.cpu_flag }} ${{ matrix.target_flag }}"
           error_string_contains: "EndOfStream"
           retry_count: 3
 
@@ -136,7 +143,7 @@ jobs:
       - name: Run Test Platforms (Unix)
         if: runner.os != 'Windows'
         run: |
-          zig build test-cli
+          zig build test-cli ${{ matrix.target_flag }}
 
       - name: Setup MSVC (Windows)
         if: runner.os == 'Windows'
@@ -165,13 +172,13 @@ jobs:
           zig-out\bin\roc.exe check ./src/PROFILING/bench_repeated_check.roc
 
       - name: zig snapshot tests
-        run: zig build snapshot -- --debug
+        run: zig build snapshot ${{ matrix.target_flag }} -- --debug
 
       # 1) in debug mode
       - name: build and execute tests, build repro executables
         uses: ./.github/actions/flaky-retry
         with:
-          command: "zig build test -Dfuzz -Dsystem-afl=false"
+          command: "zig build test -Dfuzz -Dsystem-afl=false ${{ matrix.target_flag }}"
           error_string_contains: "double roundtrip bundle"
           retry_count: 3
 
@@ -179,7 +186,7 @@ jobs:
       - name: Build and execute tests, build repro executables. All in release mode.
         uses: ./.github/actions/flaky-retry
         with:
-          command: "zig build test -Doptimize=ReleaseFast -Dfuzz -Dsystem-afl=false ${{ matrix.cpu_flag }}"
+          command: "zig build test -Doptimize=ReleaseFast -Dfuzz -Dsystem-afl=false ${{ matrix.cpu_flag }} ${{ matrix.target_flag }}"
           error_string_contains: "double roundtrip bundle"
           retry_count: 3
 
@@ -250,7 +257,7 @@ jobs:
         run: |
           git clean -fdx
           git reset --hard HEAD
-          nix develop ./src/ -c zig build && zig build snapshot && zig build test
+          nix develop ./src/ -c zig build ${{ matrix.target_flag }} && zig build snapshot ${{ matrix.target_flag }} && zig build test ${{ matrix.target_flag }}
 
   zig-cross-compile:
     needs: check-once
diff --git a/build.zig b/build.zig
index 505589aca8..7b66bdecef 100644
--- a/build.zig
+++ b/build.zig
@@ -1650,7 +1650,7 @@ pub fn build(b: *std.Build) void {
         }
         // Ensure host library is copied before running the test
         run_fx_platform_test.step.dependOn(&copy_test_fx_host.step);
-        // Ensure roc binary is built before running the test
+        // Ensure roc binary is built before running the test (tests invoke roc CLI)
         run_fx_platform_test.step.dependOn(roc_step);
         tests_summary.addRun(&run_fx_platform_test.step);
     }
@@ -2206,9 +2206,8 @@ fn addStaticLlvmOptionsToModule(mod: *std.Build.Module) !void {
     mod.linkSystemLibrary("z", link_static);
 
     if (mod.resolved_target.?.result.os.tag != .windows or mod.resolved_target.?.result.abi != .msvc) {
-        // TODO: Can this just be `mod.link_libcpp = true`? Does that make a difference?
-        // This means we rely on clang-or-zig-built LLVM, Clang, LLD libraries.
-        mod.linkSystemLibrary("c++", .{});
+        // Use Zig's bundled static libc++ to keep the binary statically linked
+        mod.link_libcpp = true;
     }
 
     if (mod.resolved_target.?.result.os.tag == .windows) {
diff --git a/src/cli/test/fx_platform_test.zig b/src/cli/test/fx_platform_test.zig
index 14fc5a4b2c..63e92e1708 100644
--- a/src/cli/test/fx_platform_test.zig
+++ b/src/cli/test/fx_platform_test.zig
@@ -734,7 +734,6 @@ test "fx platform expect with toplevel numeric" {
 // TODO: Fix test7.roc - currently fails with "UNRECOGNIZED SYNTAX" for `_ = x` pattern
 // test "fx platform test7" {
 //     const allocator = testing.allocator;
-
 //
 //     const run_result = try std.process.Child.run(.{
 //         .allocator = allocator,
@@ -769,7 +768,6 @@ test "fx platform expect with toplevel numeric" {
 // TODO: Fix test8.roc - currently fails with "UNRECOGNIZED SYNTAX" for `_ = x` pattern
 // test "fx platform test8" {
 //     const allocator = testing.allocator;
-
 //
 //     const run_result = try std.process.Child.run(.{
 //         .allocator = allocator,
@@ -804,7 +802,6 @@ test "fx platform expect with toplevel numeric" {
 // TODO: Fix test9.roc - currently fails with "UNRECOGNIZED SYNTAX" for `_ = y` pattern
 // test "fx platform test9" {
 //     const allocator = testing.allocator;
-
 //
 //     const run_result = try std.process.Child.run(.{
 //         .allocator = allocator,