diff --git a/build.zig b/build.zig
index 3a85057..94553ca 100644
--- a/build.zig
+++ b/build.zig
@@ -3,6 +3,7 @@ const std = @import("std");
 const CrossTarget = std.zig.CrossTarget;
 
 const cppflags = [_][]const u8{
+    "-DASIO_HAS_THREADS",
     "-fcolor-diagnostics",
     "-std=c++20",
     "-Wall",
@@ -65,6 +66,10 @@ pub fn build(b: *std.Build) void {
         lib.linkLibrary(tracy_dep.artifact("tracy"));
     }
     lib.linkLibrary(asio_dep.artifact("asio"));
+    if (lib.rootModuleTarget().os.tag == .windows) {
+        lib.linkSystemLibrary("mswsock");
+        lib.linkSystemLibrary("ws2_32");
+    }
     lib.linkLibCpp();
     b.installArtifact(lib);
 
diff --git a/include/cbor/cbor_in.hpp b/include/cbor/cbor_in.hpp
index a2b6bd2..e34e52b 100644
--- a/include/cbor/cbor_in.hpp
+++ b/include/cbor/cbor_in.hpp
@@ -3,7 +3,12 @@
 #include "cbor.hpp"
 
 #include <cstring>
+
+#if !defined(_WIN32)
 #include <netinet/in.h>
+#else
+#include <in6addr.h>
+#endif
 
 namespace cbor {
 
diff --git a/include/thespian/tcp.hpp b/include/thespian/tcp.hpp
index a996692..076580c 100644
--- a/include/thespian/tcp.hpp
+++ b/include/thespian/tcp.hpp
@@ -1,10 +1,15 @@
 #pragma once
 
 #include <memory>
-#include <netinet/in.h>
 #include <string_view>
 #include <vector>
 
+#if !defined(_WIN32)
+#include <netinet/in.h>
+#else
+#include <in6addr.h>
+#endif
+
 using port_t = unsigned short;
 
 namespace thespian::tcp {
diff --git a/src/backtrace.cpp b/src/backtrace.cpp
index 5e24c3d..dcf1e6c 100644
--- a/src/backtrace.cpp
+++ b/src/backtrace.cpp
@@ -1,4 +1,4 @@
-#ifndef __APPLE__
+#if !defined(_WIN32) && !defined(__APPLE__)
 
 #include <csignal>
 #include <cstdio>
diff --git a/src/executor.hpp b/src/executor.hpp
index 3237933..29feb82 100644
--- a/src/executor.hpp
+++ b/src/executor.hpp
@@ -5,10 +5,15 @@
 #include <cstdint>
 #include <functional>
 #include <memory>
-#include <netinet/in.h>
 #include <system_error>
 #include <vector>
 
+#if !defined(_WIN32)
+#include <netinet/in.h>
+#else
+#include <in6addr.h>
+#endif
+
 using port_t = unsigned short;
 
 namespace thespian::executor {
diff --git a/src/executor_asio.cpp b/src/executor_asio.cpp
index 77fbc24..7577762 100644
--- a/src/executor_asio.cpp
+++ b/src/executor_asio.cpp
@@ -1,4 +1,3 @@
-#include "asio/error_code.hpp"
 #include "asio/posix/descriptor_base.hpp"
 #include "executor.hpp"
 #include <cstddef>
@@ -11,13 +10,19 @@
 #include <asio/ip/tcp.hpp>
 #include <asio/ip/udp.hpp>
 #include <asio/local/stream_protocol.hpp>
-#include <asio/posix/stream_descriptor.hpp>
 #include <asio/signal_set.hpp>
 #include <asio/socket_base.hpp>
 #include <asio/strand.hpp>
 #include <asio/system_timer.hpp>
 #include <asio/thread.hpp>
 
+#if !defined(_WIN32)
+#include <asio/posix/stream_descriptor.hpp>
+#else
+#include <asio/windows/stream_handle.hpp>
+#include <windows.h>
+#endif
+
 #include <csignal>
 #include <vector>
 
@@ -27,7 +32,6 @@ using asio::io_context;
 using asio::string_view;
 using asio::system_timer;
 using asio::thread;
-using asio::posix::stream_descriptor;
 using std::atomic;
 using std::error_code;
 using std::function;
@@ -46,13 +50,30 @@ using std::chrono::microseconds;
 using std::chrono::system_clock;
 using std::chrono::time_point;
 
+#if !defined(_WIN32)
+using asio::posix::stream_descriptor;
+#else
+using asio::windows::stream_handle;
+#endif
+
 namespace thespian::executor {
 
 const char *MAX_THREAD_STR = getenv("MAX_THREAD"); // NOLINT
 const auto MAX_THREAD =
     static_cast<long>(atoi(MAX_THREAD_STR ? MAX_THREAD_STR : "64")); // NOLINT
 
+#if !defined(_WIN32)
 const auto threads = min(sysconf(_SC_NPROCESSORS_ONLN), MAX_THREAD);
+#else
+namespace {
+static long get_num_processors() {
+  SYSTEM_INFO si;
+  GetSystemInfo(&si);
+  return si.dwNumberOfProcessors;
+}
+} // namespace
+const auto threads = min(get_num_processors(), MAX_THREAD);
+#endif
 
 struct context_impl {
   context_impl() : asio{make_unique<io_context>(threads)} {}
@@ -62,8 +83,10 @@ struct context_impl {
 };
 
 auto context::create() -> context {
+#if !defined(_WIN32)
   if (::signal(SIGPIPE, SIG_IGN) == SIG_ERR) // NOLINT
     abort();
+#endif
   return {context_ref(new context_impl(), [](context_impl *p) { delete p; })};
 }
 
@@ -225,7 +248,7 @@ struct socket_impl {
         socket_{*ctx->asio, ::asio::ip::udp::v6()} {}
   auto bind(const in6_addr &ip, port_t port) -> error_code {
     error_code ec;
-    socket_.bind(to_endpoint_udp(ip, port), ec);
+    ec = socket_.bind(to_endpoint_udp(ip, port), ec);
     return ec;
   }
   [[nodiscard]] auto send_to(string_view data, in6_addr ip, port_t port)
@@ -305,7 +328,7 @@ struct socket_impl {
         socket_{*ctx->asio, asio::ip::tcp::v6(), fd} {}
   auto bind(const in6_addr &ip, port_t port) -> error_code {
     error_code ec;
-    socket_.bind(to_endpoint_tcp(ip, port), ec);
+    ec = socket_.bind(to_endpoint_tcp(ip, port), ec);
     return ec;
   }
   void connect(const in6_addr &ip, port_t port, socket::connect_handler h) {
@@ -382,7 +405,9 @@ void socket::write(const vector<uint8_t> &data, write_handler h) {
 void socket::read(read_handler h) { ref->read(*this, move(h)); }
 
 void socket::close() { ref->close(); }
+#if !defined(_WIN32)
 void socket::close(int fd) { ::close(fd); }
+#endif
 auto socket::release() -> int { return ref->release(); }
 
 auto socket::local_endpoint() const -> const endpoint & {
@@ -395,12 +420,12 @@ struct acceptor_impl {
         acceptor_{*ctx->asio, asio::ip::tcp::v6()}, socket_{*ctx->asio} {}
   auto bind(const in6_addr &ip, port_t port) -> error_code {
     error_code ec;
-    acceptor_.bind(to_endpoint_tcp(ip, port), ec);
+    ec = acceptor_.bind(to_endpoint_tcp(ip, port), ec);
     return ec;
   }
   auto listen() -> error_code {
     error_code ec;
-    acceptor_.listen(asio::socket_base::max_listen_connections, ec);
+    ec = acceptor_.listen(asio::socket_base::max_listen_connections, ec);
     return ec;
   }
   void accept(acceptor::handler h) {
@@ -412,7 +437,9 @@ struct acceptor_impl {
                                 t = move(weak_token)](const error_code &ec) {
           c->pending.fetch_sub(1, memory_order_relaxed);
           if (auto p = t.lock())
-            h(ec ? 0 : s->release(), ec);
+            h(ec ? static_cast<asio::ip::tcp::socket::native_handle_type>(0)
+                 : s->release(),
+              ec);
         }));
   }
   void close() { acceptor_.close(); }
@@ -454,14 +481,14 @@ namespace unx {
 
 struct socket_impl {
   explicit socket_impl(strand &strand)
-      : ctx{strand.ref->ctx}, strand_{strand.ref->strand_}, socket_{
-                                                                *ctx->asio} {}
+      : ctx{strand.ref->ctx}, strand_{strand.ref->strand_},
+        socket_{*ctx->asio} {}
   explicit socket_impl(strand &strand, int fd)
-      : ctx{strand.ref->ctx}, strand_{strand.ref->strand_}, socket_{*ctx->asio,
-                                                                    fd} {}
+      : ctx{strand.ref->ctx}, strand_{strand.ref->strand_},
+        socket_{*ctx->asio, fd} {}
   auto bind(string_view path) -> error_code {
     error_code ec;
-    socket_.bind(path, ec);
+    ec = socket_.bind(path, ec);
     return ec;
   }
   void connect(string_view path, socket::connect_handler h) {
@@ -537,12 +564,12 @@ struct acceptor_impl {
         socket_{*ctx->asio} {}
   auto bind(string_view path) -> error_code {
     error_code ec;
-    acceptor_.bind(path, ec);
+    ec = acceptor_.bind(path, ec);
     return ec;
   }
   auto listen() -> error_code {
     error_code ec;
-    acceptor_.listen(asio::socket_base::max_listen_connections, ec);
+    ec = acceptor_.listen(asio::socket_base::max_listen_connections, ec);
     return ec;
   }
   void accept(acceptor::handler h) {
@@ -554,7 +581,10 @@ struct acceptor_impl {
                                 t = move(weak_token)](const error_code &ec) {
           c->pending.fetch_sub(1, memory_order_relaxed);
           if (auto p = t.lock())
-            h(ec ? 0 : s->release(), ec);
+            h(ec ? static_cast<asio::local::stream_protocol::socket::
+                                   native_handle_type>(0)
+                 : s->release(),
+              ec);
         }));
   }
   void close() { acceptor_.close(); }
@@ -579,12 +609,13 @@ void acceptor::close() { ref->close(); }
 
 } // namespace unx
 
+#if !defined(_WIN32)
 namespace file_descriptor {
 
 struct watcher_impl {
   explicit watcher_impl(strand &strand, int fd)
-      : ctx{strand.ref->ctx}, strand_{strand.ref->strand_}, fd_{*ctx->asio,
-                                                                fd} {}
+      : ctx{strand.ref->ctx}, strand_{strand.ref->strand_},
+        fd_{*ctx->asio, fd} {}
 
   void wait_read(watcher::handler h) {
     if (!read_in_progress_) {
@@ -641,5 +672,6 @@ void watcher::wait_write(watcher::handler h) { ref->wait_write(move(h)); }
 void watcher::cancel() { ref->cancel(); }
 
 } // namespace file_descriptor
+#endif
 
 } // namespace thespian::executor
diff --git a/src/hub.cpp b/src/hub.cpp
index 6ee3eba..afc693a 100644
--- a/src/hub.cpp
+++ b/src/hub.cpp
@@ -100,7 +100,9 @@ struct hub_impl {
 
     string_view desc;
     if (msg("listen", extract(desc))) {
+#if !defined(_WIN32)
       thespian::endpoint::unx::listen(desc);
+#endif
     }
 
     if (msg("shutdown"))
diff --git a/src/instance.cpp b/src/instance.cpp
index 1061e19..d235008 100644
--- a/src/instance.cpp
+++ b/src/instance.cpp
@@ -3,7 +3,6 @@
 #include <chrono>
 #include <cstddef>
 #include <cstdint>
-#include <initializer_list>
 #include <memory>
 #include <thespian/context.hpp>
 #include <thespian/debug.hpp>
@@ -26,13 +25,25 @@
 #include <map>
 #include <memory>
 #include <mutex>
-#include <netinet/in.h>
 #include <sstream>
 #include <string>
 #include <string_view>
 #include <system_error>
 #include <utility>
 
+#if !defined(_WIN32)
+
+#include <netinet/in.h>
+
+#else
+
+#include <in6addr.h>
+#include <winsock2.h>
+#include <ws2ipdef.h>
+#include <ws2tcpip.h>
+
+#endif
+
 #ifdef TRACY_ENABLE
 #include <tracy/Tracy.hpp>
 #endif
@@ -850,6 +861,7 @@ auto udp::create(string tag) -> udp {
   return {udp_ref(new udp_impl(move(tag)), [](udp_impl *p) { delete p; })};
 }
 
+#if !defined(_WIN32)
 struct file_descriptor_impl {
   file_descriptor_impl(const file_descriptor_impl &) = delete;
   file_descriptor_impl(file_descriptor_impl &&) = delete;
@@ -913,6 +925,7 @@ void file_descriptor::wait_write(file_descriptor_impl *p) { p->wait_write(); }
 void file_descriptor::wait_read(file_descriptor_impl *p) { p->wait_read(); }
 void file_descriptor::cancel(file_descriptor_impl *p) { p->cancel(); }
 void file_descriptor::destroy(file_descriptor_impl *p) { delete p; }
+#endif
 
 struct socket_impl {
   socket_impl(const socket_impl &) = delete;
@@ -1568,6 +1581,7 @@ auto connect(in6_addr ip, port_t port, milliseconds retry_time,
 
 } // namespace tcp
 
+#if !defined(_WIN32)
 namespace unx {
 
 struct connector {
@@ -1651,8 +1665,8 @@ struct acceptor {
   string listen_path;
 
   acceptor(string_view path, mode m, handle o)
-      : a{::thespian::unx::acceptor::create(tag)}, owner{move(o)}, listen_path{
-                                                                       path} {
+      : a{::thespian::unx::acceptor::create(tag)}, owner{move(o)},
+        listen_path{path} {
     a.listen(path, m);
   }
   ~acceptor() = default;
@@ -1703,6 +1717,7 @@ auto connect(string_view path, mode m, milliseconds retry_time,
 }
 
 } // namespace unx
+#endif
 } // namespace endpoint
 
 namespace debug {
diff --git a/test/debug.cpp b/test/debug.cpp
index 0a1399c..36563fe 100644
--- a/test/debug.cpp
+++ b/test/debug.cpp
@@ -7,10 +7,16 @@
 #include <thespian/tcp.hpp>
 #include <thespian/trace.hpp>
 
-#include <array>
 #include <cstring>
 #include <memory>
 
+#if defined(_WIN32)
+#include <winsock2.h>
+#include <in6addr.h>
+#include <ws2ipdef.h>
+#include <ws2tcpip.h>
+#endif
+
 using cbor::buffer;
 using cbor::extract;
 using std::make_shared;
diff --git a/test/endpoint_tcp.cpp b/test/endpoint_tcp.cpp
index 7cdb52e..593372d 100644
--- a/test/endpoint_tcp.cpp
+++ b/test/endpoint_tcp.cpp
@@ -9,9 +9,15 @@
 #include <thespian/tcp.hpp>
 
 #include <cstring>
-#include <map>
 #include <utility>
 
+#if defined(_WIN32)
+#include <winsock2.h>
+#include <in6addr.h>
+#include <ws2ipdef.h>
+#include <ws2tcpip.h>
+#endif
+
 using cbor::any;
 using cbor::buffer;
 using cbor::extract;
diff --git a/test/endpoint_unx.cpp b/test/endpoint_unx.cpp
index 88233d2..f3783ad 100644
--- a/test/endpoint_unx.cpp
+++ b/test/endpoint_unx.cpp
@@ -7,7 +7,6 @@
 #include <thespian/unx.hpp>
 
 #include <cstring>
-#include <map>
 #include <sstream>
 #include <unistd.h>
 #include <utility>
@@ -38,6 +37,7 @@ using thespian::unx::mode;
 
 using namespace std::chrono_literals;
 
+#if !defined(_WIN32)
 namespace {
 
 struct controller {
@@ -102,3 +102,12 @@ auto endpoint_unx(context &ctx, bool &result, env_t env_) -> ::result {
       },
       "endpoint_unx", move(env_)));
 }
+
+#else
+
+auto endpoint_unx(context &, bool &result, env_t) -> ::result {
+  result = true;
+  return ok();
+}
+
+#endif
diff --git a/test/ip_tcp_client_server.cpp b/test/ip_tcp_client_server.cpp
index 3ba3c28..3cc630f 100644
--- a/test/ip_tcp_client_server.cpp
+++ b/test/ip_tcp_client_server.cpp
@@ -7,7 +7,14 @@
 #include <thespian/socket.hpp>
 #include <thespian/tcp.hpp>
 
+#if !defined(_WIN32)
 #include <netinet/in.h>
+#else
+#include <winsock2.h>
+#include <in6addr.h>
+#include <ws2ipdef.h>
+#include <ws2tcpip.h>
+#endif
 
 using cbor::buffer;
 using cbor::extract;
diff --git a/test/ip_udp_echo.cpp b/test/ip_udp_echo.cpp
index fb0c1bc..65264b0 100644
--- a/test/ip_udp_echo.cpp
+++ b/test/ip_udp_echo.cpp
@@ -6,7 +6,14 @@
 #include <thespian/timeout.hpp>
 #include <thespian/udp.hpp>
 
+#if !defined(_WIN32)
 #include <netinet/in.h>
+#else
+#include <winsock2.h>
+#include <in6addr.h>
+#include <ws2ipdef.h>
+#include <ws2tcpip.h>
+#endif
 
 using cbor::array;
 using cbor::buffer;
diff --git a/test/tests.cpp b/test/tests.cpp
index aa3c0aa..555cfde 100644
--- a/test/tests.cpp
+++ b/test/tests.cpp
@@ -16,7 +16,6 @@
 #include <mutex>
 #include <string>
 #include <utility>
-#include <vector>
 
 using cbor::buffer;
 using std::cerr;
@@ -81,8 +80,10 @@ struct logger {
 extern "C" auto runtestcase(const char *name) -> int {
   mutex trace_m;
 
+#if !defined(_WIN32)
   if (signal(SIGPIPE, SIG_IGN) == SIG_ERR) // NOLINT
     abort();
+#endif
 
   auto gdb = getenv("JITDEBUG"); // NOLINT
 
diff --git a/zig b/zig
index e12064e..31baf97 100755
--- a/zig
+++ b/zig
@@ -47,10 +47,11 @@ get_zig() {
 get_zig
 
 if [ "$1" == "cdb" ] ; then
-    rm -rf zig-cache
+    shift
+    rm -rf .zig-cache
     rm -rf .cache/cdb
 
-    $ZIG build
+    $ZIG build "$@"
 
     (echo \[ ; cat .cache/cdb/* ; echo {}\]) | perl -0777 -pe 's/,\n\{\}//igs' | jq . | grep -v 'no-default-config' > compile_commands.json
     exit 0