diff --git a/.github/workflows/build-macos.yml b/.github/workflows/build-macos.yml
index 9ca002a7..8f01f7d4 100644
--- a/.github/workflows/build-macos.yml
+++ b/.github/workflows/build-macos.yml
@@ -48,7 +48,7 @@ jobs:
         uses: actions/cache@v2
         id: cache-llvm-build
         with:
-          key: llvm-build-13-macos-v2
+          key: llvm-build-13-macos-v3
           path: llvm-build
       - name: Build LLVM
         if: steps.cache-llvm-build.outputs.cache-hit != 'true'
diff --git a/.github/workflows/linux.yml b/.github/workflows/linux.yml
index f9af94ce..661bdc56 100644
--- a/.github/workflows/linux.yml
+++ b/.github/workflows/linux.yml
@@ -51,7 +51,7 @@ jobs:
         uses: actions/cache@v2
         id: cache-llvm-build
         with:
-          key: llvm-build-13-linux-v1
+          key: llvm-build-13-linux-v2
           path: llvm-build
       - name: Build LLVM
         if: steps.cache-llvm-build.outputs.cache-hit != 'true'
@@ -192,7 +192,7 @@ jobs:
         uses: actions/cache@v2
         id: cache-llvm-build
         with:
-          key: llvm-build-13-linux-asserts-v1
+          key: llvm-build-13-linux-asserts-v2
           path: llvm-build
       - name: Build LLVM
         if: steps.cache-llvm-build.outputs.cache-hit != 'true'
diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index b2aaf131..b5194408 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -48,7 +48,7 @@ jobs:
         uses: actions/cache@v2
         id: cache-llvm-build
         with:
-          key: llvm-build-13-windows-v1
+          key: llvm-build-13-windows-v2
           path: llvm-build
       - name: Build LLVM
         if: steps.cache-llvm-build.outputs.cache-hit != 'true'
diff --git a/.gitmodules b/.gitmodules
index 8143ce84..e82a938b 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -32,3 +32,6 @@
 [submodule "lib/mingw-w64"]
 	path = lib/mingw-w64
 	url = https://github.com/mingw-w64/mingw-w64.git
+[submodule "lib/macos-minimal-sdk"]
+	path = lib/macos-minimal-sdk
+	url = https://github.com/aykevl/macos-minimal-sdk.git
diff --git a/Makefile b/Makefile
index bbce72fd..86ce7f9d 100644
--- a/Makefile
+++ b/Makefile
@@ -73,6 +73,8 @@ ifeq ($(OS),Windows_NT)
 else ifeq ($(shell uname -s),Darwin)
     MD5SUM = md5
 
+    CGO_LDFLAGS += -lxar
+
     USE_SYSTEM_BINARYEN ?= 1
 
 else ifeq ($(shell uname -s),FreeBSD)
@@ -89,7 +91,7 @@ CLANG_LIB_NAMES = clangAnalysis clangAST clangASTMatchers clangBasic clangCodeGe
 CLANG_LIBS = $(START_GROUP) $(addprefix -l,$(CLANG_LIB_NAMES)) $(END_GROUP) -lstdc++
 
 # Libraries that should be linked in for the statically linked LLD.
-LLD_LIB_NAMES = lldCOFF lldCommon lldCore lldDriver lldELF lldMachO lldMinGW lldReaderWriter lldWasm lldYAML
+LLD_LIB_NAMES = lldCOFF lldCommon lldCore lldDriver lldELF lldMachO2 lldMinGW lldReaderWriter lldWasm lldYAML
 LLD_LIBS = $(START_GROUP) $(addprefix -l,$(LLD_LIB_NAMES)) $(END_GROUP)
 
 # Other libraries that are needed to link TinyGo.
@@ -566,6 +568,7 @@ endif
 	@$(MD5SUM) test.hex
 	GOOS=linux GOARCH=arm $(TINYGO) build -size short -o test.elf       ./testdata/cgo
 	GOOS=windows GOARCH=amd64 $(TINYGO) build -size short -o test.exe   ./testdata/cgo
+	GOOS=darwin GOARCH=amd64 $(TINYGO) build              -o test       ./testdata/cgo
 ifneq ($(OS),Windows_NT)
 	# TODO: this does not yet work on Windows. Somehow, unused functions are
 	# not garbage collected.
@@ -581,6 +584,7 @@ build/release: tinygo gen-device wasi-libc $(if $(filter 1,$(USE_SYSTEM_BINARYEN
 	@mkdir -p build/release/tinygo/lib/clang/include
 	@mkdir -p build/release/tinygo/lib/CMSIS/CMSIS
 	@mkdir -p build/release/tinygo/lib/compiler-rt/lib
+	@mkdir -p build/release/tinygo/lib/macos-minimal-sdk
 	@mkdir -p build/release/tinygo/lib/mingw-w64/mingw-w64-crt/lib-common
 	@mkdir -p build/release/tinygo/lib/mingw-w64/mingw-w64-headers/defaults
 	@mkdir -p build/release/tinygo/lib/musl/arch
@@ -604,6 +608,7 @@ endif
 	@cp -rp lib/compiler-rt/lib/builtins build/release/tinygo/lib/compiler-rt/lib
 	@cp -rp lib/compiler-rt/LICENSE.TXT  build/release/tinygo/lib/compiler-rt
 	@cp -rp lib/compiler-rt/README.txt   build/release/tinygo/lib/compiler-rt
+	@cp -rp lib/macos-minimal-sdk/*      build/release/tinygo/lib/macos-minimal-sdk
 	@cp -rp lib/musl/arch/aarch64        build/release/tinygo/lib/musl/arch
 	@cp -rp lib/musl/arch/arm            build/release/tinygo/lib/musl/arch
 	@cp -rp lib/musl/arch/generic        build/release/tinygo/lib/musl/arch
diff --git a/builder/build.go b/builder/build.go
index 42a3dd33..c4831de0 100644
--- a/builder/build.go
+++ b/builder/build.go
@@ -107,6 +107,9 @@ func Build(pkgName, outpath string, config *compileopts.Config, action func(Buil
 	root := goenv.Get("TINYGOROOT")
 	var libcDependencies []*compileJob
 	switch config.Target.Libc {
+	case "darwin-libSystem":
+		job := makeDarwinLibSystemJob(config, dir)
+		libcDependencies = append(libcDependencies, job)
 	case "musl":
 		job, unlock, err := Musl.load(config, dir)
 		if err != nil {
diff --git a/builder/darwin-libsystem.go b/builder/darwin-libsystem.go
new file mode 100644
index 00000000..32882581
--- /dev/null
+++ b/builder/darwin-libsystem.go
@@ -0,0 +1,58 @@
+package builder
+
+import (
+	"path/filepath"
+	"strings"
+
+	"github.com/tinygo-org/tinygo/compileopts"
+	"github.com/tinygo-org/tinygo/goenv"
+)
+
+// Create a job that builds a Darwin libSystem.dylib stub library. This library
+// contains all the symbols needed so that we can link against it, but it
+// doesn't contain any real symbol implementations.
+func makeDarwinLibSystemJob(config *compileopts.Config, tmpdir string) *compileJob {
+	return &compileJob{
+		description: "compile Darwin libSystem.dylib",
+		run: func(job *compileJob) (err error) {
+			arch := strings.Split(config.Triple(), "-")[0]
+			job.result = filepath.Join(tmpdir, "libSystem.dylib")
+			objpath := filepath.Join(tmpdir, "libSystem.o")
+			inpath := filepath.Join(goenv.Get("TINYGOROOT"), "lib/macos-minimal-sdk/src", arch, "libSystem.s")
+
+			// Compile assembly file to object file.
+			flags := []string{
+				"-nostdlib",
+				"--target=" + config.Triple(),
+				"-c",
+				"-o", objpath,
+				inpath,
+			}
+			if config.Options.PrintCommands != nil {
+				config.Options.PrintCommands("clang", flags...)
+			}
+			err = runCCompiler(flags...)
+			if err != nil {
+				return err
+			}
+
+			// Link object file to dynamic library.
+			platformVersion := strings.TrimPrefix(strings.Split(config.Triple(), "-")[2], "macosx")
+			flags = []string{
+				"-flavor", "darwinnew",
+				"-demangle",
+				"-dynamic",
+				"-dylib",
+				"-arch", arch,
+				"-platform_version", "macos", platformVersion, platformVersion,
+				"-install_name", "/usr/lib/libSystem.B.dylib",
+				"-o", job.result,
+				objpath,
+			}
+			if config.Options.PrintCommands != nil {
+				config.Options.PrintCommands("ld.lld", flags...)
+			}
+			return link("ld.lld", flags...)
+		},
+	}
+}
diff --git a/builder/lld.cpp b/builder/lld.cpp
index 5a9ad8a2..0543a3ea 100644
--- a/builder/lld.cpp
+++ b/builder/lld.cpp
@@ -11,6 +11,11 @@ bool tinygo_link_elf(int argc, char **argv) {
 	return lld::elf::link(args, false, llvm::outs(), llvm::errs());
 }
 
+bool tinygo_link_macho(int argc, char **argv) {
+	std::vector<const char*> args(argv, argv + argc);
+	return lld::macho::link(args, false, llvm::outs(), llvm::errs());
+}
+
 bool tinygo_link_mingw(int argc, char **argv) {
 	std::vector<const char*> args(argv, argv + argc);
 	return lld::mingw::link(args, false, llvm::outs(), llvm::errs());
diff --git a/builder/tools-builtin.go b/builder/tools-builtin.go
index e5ecd424..5474e3e5 100644
--- a/builder/tools-builtin.go
+++ b/builder/tools-builtin.go
@@ -14,6 +14,7 @@ import (
 #include <stdlib.h>
 bool tinygo_clang_driver(int argc, char **argv);
 bool tinygo_link_elf(int argc, char **argv);
+bool tinygo_link_macho(int argc, char **argv);
 bool tinygo_link_mingw(int argc, char **argv);
 bool tinygo_link_wasm(int argc, char **argv);
 */
@@ -27,8 +28,13 @@ const hasBuiltinTools = true
 // linking statically with LLVM (with the byollvm build tag).
 func RunTool(tool string, args ...string) error {
 	linker := "elf"
-	if tool == "ld.lld" && len(args) >= 2 && args[0] == "-m" && args[1] == "i386pep" {
-		linker = "mingw"
+	if tool == "ld.lld" && len(args) >= 2 {
+		if args[0] == "-m" && args[1] == "i386pep" {
+			linker = "mingw"
+		} else if args[0] == "-flavor" {
+			linker = args[1]
+			args = args[2:]
+		}
 	}
 	args = append([]string{"tinygo:" + tool}, args...)
 
@@ -48,6 +54,8 @@ func RunTool(tool string, args ...string) error {
 		ok = C.tinygo_clang_driver(C.int(len(args)), (**C.char)(buf))
 	case "ld.lld":
 		switch linker {
+		case "darwinnew":
+			ok = C.tinygo_link_macho(C.int(len(args)), (**C.char)(buf))
 		case "elf":
 			ok = C.tinygo_link_elf(C.int(len(args)), (**C.char)(buf))
 		case "mingw":
diff --git a/compileopts/config.go b/compileopts/config.go
index f33a4b1a..392ef223 100644
--- a/compileopts/config.go
+++ b/compileopts/config.go
@@ -225,6 +225,11 @@ func (c *Config) CFlags() []string {
 		cflags = append(cflags, strings.ReplaceAll(flag, "{root}", goenv.Get("TINYGOROOT")))
 	}
 	switch c.Target.Libc {
+	case "darwin-libSystem":
+		root := goenv.Get("TINYGOROOT")
+		cflags = append(cflags,
+			"--sysroot="+filepath.Join(root, "lib/macos-minimal-sdk/src"),
+		)
 	case "picolibc":
 		root := goenv.Get("TINYGOROOT")
 		picolibcDir := filepath.Join(root, "lib", "picolibc", "newlib", "libc")
diff --git a/compileopts/target.go b/compileopts/target.go
index 9e341537..79631001 100644
--- a/compileopts/target.go
+++ b/compileopts/target.go
@@ -272,8 +272,16 @@ func defaultTarget(goos, goarch, triple string) (*TargetSpec, error) {
 		spec.Features = "+neon"
 	}
 	if goos == "darwin" {
-		spec.CFlags = append(spec.CFlags, "-isysroot", "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk")
-		spec.LDFlags = append(spec.LDFlags, "-Wl,-dead_strip")
+		spec.Linker = "ld.lld"
+		spec.Libc = "darwin-libSystem"
+		arch := strings.Split(triple, "-")[0]
+		platformVersion := strings.TrimPrefix(strings.Split(triple, "-")[2], "macosx")
+		spec.LDFlags = append(spec.LDFlags,
+			"-flavor", "darwinnew",
+			"-dead_strip",
+			"-arch", arch,
+			"-platform_version", "macos", platformVersion, platformVersion,
+		)
 	} else if goos == "linux" {
 		spec.Linker = "ld.lld"
 		spec.RTLib = "compiler-rt"
diff --git a/lib/macos-minimal-sdk b/lib/macos-minimal-sdk
new file mode 160000
index 00000000..a9a5a723
--- /dev/null
+++ b/lib/macos-minimal-sdk
@@ -0,0 +1 @@
+Subproject commit a9a5a723a6d743a8562bbb62218c6f1361a05994