diff --git a/config-unix.mk b/config-unix.mk
index 862af2d4..98d89397 100644
--- a/config-unix.mk
+++ b/config-unix.mk
@@ -21,7 +21,8 @@
 CC ?= $(PREFIX)gcc
 AR ?= $(PREFIX)ar
 E=
-CFLAGS=--std=gnu89 -g
+CSTDFLAG=--std=c89 -pedantic
+CFLAGS=-g
 CPPFLAGS += -Isrc/ev
 LINKFLAGS=-lm
 
@@ -80,13 +81,13 @@ uv.a: src/uv-unix.o src/uv-common.o src/uv-platform.o src/ev/ev.o src/uv-eio.o s
 		src/eio/eio.o $(CARES_OBJS)
 
 src/uv-platform.o: src/$(UV_OS_FILE) include/uv.h include/uv-unix.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) -c src/$(UV_OS_FILE) -o src/uv-platform.o
+	$(CC) $(CSTDFLAG) $(CPPFLAGS) $(CFLAGS) -c src/$(UV_OS_FILE) -o src/uv-platform.o
 
 src/uv-unix.o: src/uv-unix.c include/uv.h include/uv-unix.h
-	$(CC) $(CPPFLAGS) -Ieio $(CFLAGS) -c src/uv-unix.c -o src/uv-unix.o
+	$(CC) $(CSTDFLAG) $(CPPFLAGS) -Ieio $(CFLAGS) -c src/uv-unix.c -o src/uv-unix.o
 
 src/uv-common.o: src/uv-common.c include/uv.h include/uv-unix.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) -c src/uv-common.c -o src/uv-common.o
+	$(CC) $(CSTDFLAG) $(CPPFLAGS) $(CFLAGS) -c src/uv-common.c -o src/uv-common.o
 
 src/ev/ev.o: src/ev/ev.c
 	$(CC) $(CPPFLAGS) $(CFLAGS) -c src/ev/ev.c -o src/ev/ev.o -DEV_CONFIG_H=\"$(EV_CONFIG)\"
@@ -101,7 +102,7 @@ src/eio/eio.o: src/eio/eio.c
 	$(CC) $(EIO_CPPFLAGS) $(CFLAGS) -c src/eio/eio.c -o src/eio/eio.o
 
 src/uv-eio.o: src/uv-eio.c
-	$(CC) $(CPPFLAGS) -Isrc/eio/ $(CFLAGS) -c src/uv-eio.c -o src/uv-eio.o
+	$(CC) $(CPPFLAGS) -Isrc/eio/ $(CSTDFLAG) $(CFLAGS) -c src/uv-eio.c -o src/uv-eio.o
 
 
 clean-platform:
diff --git a/include/eio.h b/include/eio.h
index 1d597e1f..3dd32676 100644
--- a/include/eio.h
+++ b/include/eio.h
@@ -176,7 +176,7 @@ enum
 enum
 {
   EIO_MCL_CURRENT = 1,
-  EIO_MCL_FUTURE  = 2,
+  EIO_MCL_FUTURE  = 2
 };
 
 /* request priorities */
@@ -184,7 +184,7 @@ enum
 enum {
   EIO_PRI_MIN     = -4,
   EIO_PRI_MAX     =  4,
-  EIO_PRI_DEFAULT =  0,
+  EIO_PRI_DEFAULT =  0
 };
 
 /* eio request structure */
diff --git a/include/uv.h b/include/uv.h
index aa27179a..b93d243d 100644
--- a/include/uv.h
+++ b/include/uv.h
@@ -167,7 +167,7 @@ struct uv_req_s {
   uv_req_type type;
   /* public */
   uv_handle_t* handle;
-  void* cb;
+  void *(*cb)(void *);
   void* data;
   /* private */
   UV_REQ_PRIVATE_FIELDS
@@ -176,7 +176,7 @@ struct uv_req_s {
 /*
  * Initialize a request for use with uv_write, uv_shutdown, or uv_connect.
  */
-void uv_req_init(uv_req_t* req, uv_handle_t* handle, void* cb);
+void uv_req_init(uv_req_t* req, uv_handle_t* handle, void *(*cb)(void *));
 
 int uv_shutdown(uv_req_t* req);
 
diff --git a/src/uv-unix.c b/src/uv-unix.c
index 17b18574..94944bab 100644
--- a/src/uv-unix.c
+++ b/src/uv-unix.c
@@ -996,7 +996,9 @@ int uv_write(uv_req_t* req, uv_buf_t bufs[], int bufcnt) {
   memcpy(req->bufs, bufs, bufcnt * sizeof(uv_buf_t));
   req->bufcnt = bufcnt;
 
-  // fprintf(stderr, "cnt: %d bufs: %p bufsml: %p\n", bufcnt, req->bufs, req->bufsml);
+  /*
+   * fprintf(stderr, "cnt: %d bufs: %p bufsml: %p\n", bufcnt, req->bufs, req->bufsml);
+   */
 
   req->write_index = 0;
   tcp->write_queue_size += uv__buf_count(bufs, bufcnt);
@@ -1096,7 +1098,7 @@ int uv_read_stop(uv_stream_t* stream) {
 }
 
 
-void uv_req_init(uv_req_t* req, uv_handle_t* handle, void* cb) {
+void uv_req_init(uv_req_t* req, uv_handle_t* handle, void *(*cb)(void *)) {
   uv_counters()->req_init++;
   req->type = UV_UNKNOWN_REQ;
   req->cb = cb;
@@ -1556,6 +1558,7 @@ int uv_getaddrinfo(uv_getaddrinfo_t* handle,
                    const char* hostname,
                    const char* service,
                    const struct addrinfo* hints) {
+  eio_req* req;
   uv_eio_init();
 
   if (handle == NULL || cb == NULL ||
@@ -1584,7 +1587,7 @@ int uv_getaddrinfo(uv_getaddrinfo_t* handle,
 
   uv_ref();
 
-  eio_req* req = eio_custom(getaddrinfo_thread_proc, EIO_PRI_DEFAULT,
+  req = eio_custom(getaddrinfo_thread_proc, EIO_PRI_DEFAULT,
       uv_getaddrinfo_done, handle);
   assert(req);
   assert(req->data == handle);
diff --git a/src/uv-win.c b/src/uv-win.c
index 1f54e07f..93bf64d1 100644
--- a/src/uv-win.c
+++ b/src/uv-win.c
@@ -513,7 +513,7 @@ void uv_init() {
 }
 
 
-void uv_req_init(uv_req_t* req, uv_handle_t* handle, void* cb) {
+void uv_req_init(uv_req_t* req, uv_handle_t* handle, void *(*cb)(void *)) {
   uv_counters()->req_init++;
   req->type = UV_UNKNOWN_REQ;
   req->flags = 0;
diff --git a/test/echo-server.c b/test/echo-server.c
index ea01631d..9addc546 100644
--- a/test/echo-server.c
+++ b/test/echo-server.c
@@ -82,7 +82,7 @@ static void after_read(uv_stream_t* handle, ssize_t nread, uv_buf_t buf) {
     }
 
     req = (uv_req_t*) malloc(sizeof *req);
-    uv_req_init(req, (uv_handle_t*)handle, after_shutdown);
+    uv_req_init(req, (uv_handle_t*)handle, (void *(*)(void *))after_shutdown);
     uv_shutdown(req);
 
     return;
@@ -108,7 +108,7 @@ static void after_read(uv_stream_t* handle, ssize_t nread, uv_buf_t buf) {
 
   wr = (write_req_t*) malloc(sizeof *wr);
 
-  uv_req_init(&wr->req, (uv_handle_t*)handle, after_write);
+  uv_req_init(&wr->req, (uv_handle_t*)handle, (void *(*)(void *))after_write);
   wr->buf.base = buf.base;
   wr->buf.len = nread;
   if (uv_write(&wr->req, &wr->buf, 1)) {
@@ -135,7 +135,7 @@ static void on_connection(uv_handle_t* server, int status) {
   int r;
 
   if (status != 0) {
-    fprintf(stderr, "Connect error %d\n", uv_last_error());
+    fprintf(stderr, "Connect error %d\n", uv_last_error().code);
   }
   ASSERT(status == 0);
 
diff --git a/test/test-callback-stack.c b/test/test-callback-stack.c
index 286fef39..5b12c8b9 100644
--- a/test/test-callback-stack.c
+++ b/test/test-callback-stack.c
@@ -70,7 +70,7 @@ static void shutdown_cb(uv_req_t* req, int status) {
 static void read_cb(uv_stream_t* tcp, ssize_t nread, uv_buf_t buf) {
   ASSERT(nested == 0 && "read_cb must be called from a fresh stack");
 
-  printf("Read. nread == %d\n", nread);
+  printf("Read. nread == %d\n", (int)nread);
   free(buf.base);
 
   if (nread == 0) {
@@ -97,7 +97,7 @@ static void read_cb(uv_stream_t* tcp, ssize_t nread, uv_buf_t buf) {
   /* from a fresh stack. */
   if (bytes_received == sizeof MESSAGE) {
     nested++;
-    uv_req_init(&shutdown_req, (uv_handle_t*)tcp, shutdown_cb);
+    uv_req_init(&shutdown_req, (uv_handle_t*)tcp, (void *(*)(void *))shutdown_cb);
 
     puts("Shutdown");
 
@@ -167,7 +167,7 @@ static void connect_cb(uv_req_t* req, int status) {
   buf.base = (char*) &MESSAGE;
   buf.len = sizeof MESSAGE;
 
-  uv_req_init(&write_req, req->handle, write_cb);
+  uv_req_init(&write_req, req->handle, (void *(*)(void *))write_cb);
 
   if (uv_write(&write_req, &buf, 1)) {
     FATAL("uv_write failed");
@@ -191,7 +191,9 @@ TEST_IMPL(callback_stack) {
   puts("Connecting...");
 
   nested++;
-  uv_req_init(&connect_req, (uv_handle_t*)&client, connect_cb);
+  uv_req_init(&connect_req, (uv_handle_t*)&client,
+      (void *(*)(void *))connect_cb);
+
   if (uv_tcp_connect(&connect_req, addr)) {
     FATAL("uv_tcp_connect failed");
   }
diff --git a/test/test-connection-fail.c b/test/test-connection-fail.c
index e9120b90..9fc3f0ba 100644
--- a/test/test-connection-fail.c
+++ b/test/test-connection-fail.c
@@ -103,7 +103,7 @@ void connection_fail(uv_connect_cb connect_cb) {
 
   /* We are never doing multiple reads/connects at a time anyway. */
   /* so these handles can be pre-initialized. */
-  uv_req_init(&req, (uv_handle_t*)&tcp, connect_cb);
+  uv_req_init(&req, (uv_handle_t*)&tcp, (void *(*)(void *))connect_cb);
 
   uv_tcp_bind(&tcp, client_addr);
   r = uv_tcp_connect(&req, server_addr);
diff --git a/test/test-delayed-accept.c b/test/test-delayed-accept.c
index b254ccb0..eabf4818 100644
--- a/test/test-delayed-accept.c
+++ b/test/test-delayed-accept.c
@@ -178,7 +178,7 @@ static void client_connect() {
   r = uv_tcp_init(client);
   ASSERT(r == 0);
 
-  uv_req_init(connect_req, (uv_handle_t*)client, connect_cb);
+  uv_req_init(connect_req, (uv_handle_t*)client, (void *(*)(void *))connect_cb);
   r = uv_tcp_connect(connect_req, addr);
   ASSERT(r == 0);
 }
diff --git a/test/test-ping-pong.c b/test/test-ping-pong.c
index 7004fc60..34de78b5 100644
--- a/test/test-ping-pong.c
+++ b/test/test-ping-pong.c
@@ -82,7 +82,8 @@ static void pinger_write_ping(pinger_t* pinger) {
   buf.len = strlen(PING);
 
   req = (uv_req_t*)malloc(sizeof(*req));
-  uv_req_init(req, (uv_handle_t*)(&pinger->tcp), pinger_after_write);
+  uv_req_init(req, (uv_handle_t*)(&pinger->tcp),
+      (void *(*)(void *))pinger_after_write);
 
   if (uv_write(req, &buf, 1)) {
     FATAL("uv_write failed");
@@ -158,7 +159,7 @@ static void pinger_new() {
   /* We are never doing multiple reads/connects at a time anyway. */
   /* so these handles can be pre-initialized. */
   uv_req_init(&pinger->connect_req, (uv_handle_t*)(&pinger->tcp),
-      pinger_on_connect);
+      (void *(*)(void *))pinger_on_connect);
 
   r = uv_tcp_connect(&pinger->connect_req, server_addr);
   ASSERT(!r);
@@ -195,7 +196,7 @@ static void pinger_v6_new() {
   /* We are never doing multiple reads/connects at a time anyway. */
   /* so these handles can be pre-initialized. */
   uv_req_init(&pinger->connect_req, (uv_handle_t*)(&pinger->tcp),
-      pinger_on_connect);
+      (void *(*)(void *))pinger_on_connect);
 
   r = uv_tcp_connect6(&pinger->connect_req, server_addr);
   ASSERT(!r);
diff --git a/test/test-shutdown-eof.c b/test/test-shutdown-eof.c
index e986a193..8a960c9e 100644
--- a/test/test-shutdown-eof.c
+++ b/test/test-shutdown-eof.c
@@ -102,7 +102,7 @@ static void connect_cb(uv_req_t *req, int status) {
   uv_write(&write_req, &qbuf, 1);
 
   /* Shutdown our end of the connection.  */
-  uv_req_init(&shutdown_req, (uv_handle_t*)&tcp, shutdown_cb);
+  uv_req_init(&shutdown_req, (uv_handle_t*)&tcp, (void *(*)(void *))shutdown_cb);
   uv_shutdown(&shutdown_req);
 
   called_connect_cb++;
@@ -165,7 +165,7 @@ TEST_IMPL(shutdown_eof) {
   r = uv_tcp_init(&tcp);
   ASSERT(!r);
 
-  uv_req_init(&connect_req, (uv_handle_t*) &tcp, connect_cb);
+  uv_req_init(&connect_req, (uv_handle_t*) &tcp, (void *(*)(void *))connect_cb);
   r = uv_tcp_connect(&connect_req, server_addr);
   ASSERT(!r);
 
diff --git a/test/test-tcp-writealot.c b/test/test-tcp-writealot.c
index b0334899..4e305a9f 100644
--- a/test/test-tcp-writealot.c
+++ b/test/test-tcp-writealot.c
@@ -144,7 +144,7 @@ static void connect_cb(uv_req_t* req, int status) {
     req = (uv_req_t*)malloc(sizeof *req);
     ASSERT(req != NULL);
 
-    uv_req_init(req, (uv_handle_t*)tcp, write_cb);
+    uv_req_init(req, (uv_handle_t*)tcp, (void *(*)(void *))write_cb);
     r = uv_write(req, (uv_buf_t*)&send_bufs, CHUNKS_PER_WRITE);
     ASSERT(r == 0);
   }
@@ -152,7 +152,7 @@ static void connect_cb(uv_req_t* req, int status) {
   /* Shutdown on drain. FIXME: dealloc req? */
   req = (uv_req_t*) malloc(sizeof(uv_req_t));
   ASSERT(req != NULL);
-  uv_req_init(req, (uv_handle_t*)tcp, shutdown_cb);
+  uv_req_init(req, (uv_handle_t*)tcp, (void *(*)(void *))shutdown_cb);
   r = uv_shutdown(req);
   ASSERT(r == 0);
 
@@ -160,7 +160,7 @@ static void connect_cb(uv_req_t* req, int status) {
   req = (uv_req_t*)malloc(sizeof *req);
   ASSERT(req != NULL);
 
-  uv_req_init(req, (uv_handle_t*)tcp, read_cb);
+  uv_req_init(req, (uv_handle_t*)tcp, (void *(*)(void *))read_cb);
   r = uv_read_start((uv_stream_t*)tcp, alloc_cb, read_cb);
   ASSERT(r == 0);
 }
@@ -184,7 +184,7 @@ TEST_IMPL(tcp_writealot) {
   r = uv_tcp_init(client);
   ASSERT(r == 0);
 
-  uv_req_init(connect_req, (uv_handle_t*)client, connect_cb);
+  uv_req_init(connect_req, (uv_handle_t*)client, (void *(*)(void *))connect_cb);
   r = uv_tcp_connect(connect_req, addr);
   ASSERT(r == 0);