diff --git a/d/.gitignore b/d/.gitignore
new file mode 100644
index 0000000..5e56e04
--- /dev/null
+++ b/d/.gitignore
@@ -0,0 +1 @@
+/bin
diff --git a/d/Makefile b/d/Makefile
new file mode 100644
index 0000000..4c3170f
--- /dev/null
+++ b/d/Makefile
@@ -0,0 +1,50 @@
+DMD=bin/dmd2/linux/bin64/dmd
+DMD_VERSION=2.074.0
+LDC=bin/ldc2-$(LDC_VERSION)-linux-$(PLATFORM)/bin/ldc2
+LDC_VERSION=1.3.0
+DFLAGS=-g
+PLATFORM=x86_64
+
+all: bin/serial_opt bin/async_opt bin/async_queue_opt bin/async_atomic_opt
+
+################################################################################
+# Auto-bootstrap DMD & LDC for outdated Debian/Ubuntu
+################################################################################
+
+bin:
+	mkdir -p $@
+
+bin/dmd2: | bin
+	curl -fSL --retry 3 "http://downloads.dlang.org/releases/2.x/$(DMD_VERSION)/dmd.$(DMD_VERSION).linux.tar.xz" | tar -Jxf - -C $|
+bin/dmd2/linux/bin64/dmd: | bin/dmd2
+
+bin/ldc2-$(LDC_VERSION)-linux-$(PLATFORM): | bin
+	curl -fSL --retry 3 "https://github.com/ldc-developers/ldc/releases/download/v$(LDC_VERSION)/ldc2-$(LDC_VERSION)-linux-$(PLATFORM).tar.xz" \
+	| tar -Jxf - -C $|
+
+bin/ldc2-$(LDC_VERSION)-linux-$(PLATFORM)/bin/ldc2: | bin/ldc2-$(LDC_VERSION)-linux-$(PLATFORM)
+
+bin/%_opt: %.d $(LDC) | bin
+	$(LDC) -g -O4 -mcpu=native -release $(DFLAGS) $< -of$@
+
+bin/%: %.d $(DMD) | bin
+	$(DMD) $(DFLAGS) $< -of$@
+
+################################################################################
+# Programs
+################################################################################
+
+BENCHMARK=../async-io/benchmark.sh
+TEST=../async-io/test.sh
+
+benchmark: bin/serial_opt bin/async_opt
+	$(BENCHMARK) $< $(word 2, $^)
+
+benchmark_queue: bin/serial_opt bin/async_queue_opt
+	$(BENCHMARK) $< $(word 2, $^)
+
+benchmark_atomic: bin/serial_opt bin/async_atomic_opt
+	$(BENCHMARK) $< $(word 2, $^)
+
+test: bin/async_opt
+	$(TEST) $<
diff --git a/d/README.md b/d/README.md
new file mode 100644
index 0000000..04791a0
--- /dev/null
+++ b/d/README.md
@@ -0,0 +1,6 @@
+
+Async implementations:
+
+- `async.d` -> Out of the box [`std.concurrency`](https://dlang.org/phobos/std_concurrency.html)
+- `async_queue.d` -> Locking queue
+- `async_atomic.d` -> Atomic version (cheated)
diff --git a/d/async.d b/d/async.d
new file mode 100644
index 0000000..a3984a2
--- /dev/null
+++ b/d/async.d
@@ -0,0 +1,26 @@
+#!/usr/bin/env rdmd
+
+__gshared int maxInt;
+__gshared int currentInt;
+
+void main(string[] args)
+{
+    import std.conv, std.stdio;
+    import std.concurrency;
+    auto pid = spawn({
+        for (;;)
+        {
+            if (receiveOnly!bool)
+                printf("%d", currentInt++);
+            else
+                goto end;
+        }
+end:
+    });
+    auto n = args[1].to!int;
+    pid.setMaxMailboxSize(n + 10, OnCrowding.ignore);
+    foreach (i; 0..n)
+        pid.send(true);
+
+    pid.send(false);
+}
diff --git a/d/async_atomic.d b/d/async_atomic.d
new file mode 100644
index 0000000..dd8bbf7
--- /dev/null
+++ b/d/async_atomic.d
@@ -0,0 +1,49 @@
+#!/usr/bin/env rdmd
+
+__gshared int currentInt;
+
+enum States {
+    pending,
+    printInt,
+    exit
+}
+shared States state;
+
+import core.sync.mutex;
+
+void main(string[] args)
+{
+    import std.conv, std.stdio;
+    import std.concurrency;
+    import core.atomic;
+    auto pid = spawn({
+        with (States)
+        for_label: for (;;) {
+            final switch (state.atomicLoad) {
+            case printInt:
+                    currentInt.write;
+                    state.atomicStore(States.pending);
+                goto for_label;
+            case pending:
+                goto for_label;
+            case exit:
+                goto end;
+            }
+        }
+        end:
+    });
+    auto n = args[1].to!int;
+    foreach (i; 0..n)
+    {
+        state.atomicStore(States.printInt);
+        for (;;) {
+            if (state.atomicLoad != States.printInt) {
+                currentInt++;
+                goto end;
+            }
+        }
+        end:
+    }
+
+    state.atomicStore(States.exit);
+}
diff --git a/d/async_queue.d b/d/async_queue.d
new file mode 100644
index 0000000..82404ab
--- /dev/null
+++ b/d/async_queue.d
@@ -0,0 +1,67 @@
+#!/usr/bin/env dub
+/+dub.sdl:
+name "async_queue"
+dependency "emsi_containers" version="~>0.5.3"
++/
+
+import core.sync.mutex : Mutex;
+
+// this isn't faster than Mutex
+class SpinLock : Object.Monitor
+{
+    import core.atomic, core.thread;
+    void lock() { while (!cas(&locked, false, true)) { Thread.yield(); } }
+    void unlock() { atomicStore!(MemoryOrder.rel)(locked, false); }
+    shared bool locked;
+}
+
+void main(string[] args)
+//@nogc
+{
+    import std.conv, std.stdio;
+    import std.concurrency;
+    import core.memory;
+    GC.disable();
+
+    auto n = args[1].to!int;
+
+    import std.experimental.allocator : make;
+    import std.experimental.allocator.mallocator: Mallocator;
+    alias alloc = Mallocator.instance;
+
+    __gshared Mutex mutex;
+    //__gshared SpinLock mutex;
+    mutex = alloc.make!(typeof(mutex));
+
+    import std.container.dlist;
+    //__gshared DList!(void function() @safe) queue;
+    __gshared DList!int queue;
+
+    __gshared bool done;
+    scope(exit) done = true;
+
+    auto pid = spawn({
+        typeof(queue) localQueue;
+        for (;;) {
+            synchronized(mutex) {
+                if (!queue.empty) {
+                    localQueue = queue;
+                    queue = typeof(queue).init;
+                }
+            }
+
+            foreach (e; localQueue[])
+                "%d".printf(e);
+                //e();
+
+            if (done)
+                goto end;
+        }
+end:
+    });
+
+    foreach (i; 0..n)
+        synchronized(mutex)
+            queue ~= i;
+            //queue ~= { 0.write; };
+}
diff --git a/d/serial.d b/d/serial.d
new file mode 100644
index 0000000..24e88dc
--- /dev/null
+++ b/d/serial.d
@@ -0,0 +1,8 @@
+#!/usr/bin/env rdmd
+
+void main(string[] args)
+{
+    import std.conv, std.stdio;
+    foreach (i; 0..args[1].to!int)
+        "%d".printf(i);
+}