diff --git a/core/writer.c b/core/writer.c
new file mode 100644
index 00000000..3ffedb99
--- /dev/null
+++ b/core/writer.c
@@ -0,0 +1,67 @@
+// status could be NNN or NNN message
+int uwsgi_response_prepare_headers(struct wsgi_request *wsgi_req, char *status, uint16_t status_len) {
+}
+
+//each protocol has its header generator
+int uwsgi_response_add_header(struct wsgi_request *wsgi_req, char *key, uint16_t key_len, char *value, uint16_t value_len) {
+
+	if (wsgi_req->headers_sent) return -1;
+
+	if (!wsgi_req->headers) {
+		wsgi_req->headers = uwsgi_buffer_new(uwsgi.page_size);
+		wsgi_req->headers->limit = UMAX16;
+	}
+
+	struct uwsgi_buffer *hh = wsgi_req->socket->proto_add_header(wsgi_req, key, key_len, value, value_len);
+	if (!hh) return -1;
+	if (uwsgi_buffer_append(wsgi_req->headers, hh->buf, hh->pos)) goto error;
+	uwsgi_buffer_destroy(hh);
+	return 0;
+error:
+	uwsgi_buffer_destroy(hh);
+	return -1;
+}
+
+// send the headers in a non blocking-way
+int uwsgi_response_commit_headers(struct wsgi_request *wsgi_req) {
+	struct uwsgi_buffer *ub = wsgi_req->headers;	
+	if (!ub) return UWSGI_OK;
+
+	ssize_t remains = ub->pos - wsgi_req->headers_write_pos;
+	if (!remains) return UWSGI_OK;
+
+	// this is special, as it returns -1 on error and OK/AGAIN otherwise
+	int ret = wsgi_req->socket->proto_fix_headers(wsgi_req);
+	if (len < 0) {
+		wsgi_req->write_errors++;	
+	}
+	if (len == remains) {
+		wsgi_req->headers_sent = 1;
+		return UWSGI_OK;
+	}
+}
+
+int uwsgi_response_write_body_do(struct wsgi_request *wsgi_req, char *buf, size_t len) {
+	wsgi_req->response_write_body_pos = 0;
+
+	for(;;) {
+		int ret = wsgi_req->socket->proto_write(wsgi_req, buf, len);
+		if (ret < 0) {
+			if (!uwsgi.ignore_write_errors) {
+				uwsgi_error("uwsgi_response_write_body_do()");
+			}
+			return -1;
+		}
+		if (ret == UWSGI_OK) {
+			break;
+		}
+		ret = uwsgi.wait_write_hook(wsgi_req);			
+		if (ret < 0) return -1;
+		// callback based hook...
+		if (ret == UWSGI_AGAIN) return UWSGI_AGAIN;
+	}
+
+	wsgi_req->response_size += wsgi_req->response_write_body_pos;
+
+	return UWSGI_OK;	
+}
diff --git a/plugins/psgi/psgi_plugin.c b/plugins/psgi/psgi_plugin.c
index 28418bff..0e863f94 100644
--- a/plugins/psgi/psgi_plugin.c
+++ b/plugins/psgi/psgi_plugin.c
@@ -23,8 +23,6 @@ struct uwsgi_option uwsgi_perl_options[] = {
 
 };
 
-extern struct http_status_codes hsc[];
-
 SV *uwsgi_perl_obj_new(char *class, size_t class_len) {
 
 	SV *newobj;
@@ -377,11 +375,6 @@ int uwsgi_perl_init(){
 
 	PERL_SET_CONTEXT(uperl.main[0]);
 
-	// filling http status codes
-	for (http_sc = hsc; http_sc->message != NULL; http_sc++) {
-		http_sc->message_size = strlen(http_sc->message);
-	}
-
 #ifdef PERL_VERSION_STRING
 	uwsgi_log_initial("initialized Perl %s main interpreter at %p\n", PERL_VERSION_STRING, uperl.main[0]);
 #else
diff --git a/plugins/psgi/psgi_response.c b/plugins/psgi/psgi_response.c
index f292a256..1beca059 100644
--- a/plugins/psgi/psgi_response.c
+++ b/plugins/psgi/psgi_response.c
@@ -67,36 +67,8 @@ int psgi_response(struct wsgi_request *wsgi_req, AV *response) {
 	status_code = av_fetch(response, 0, 0);
 	if (!status_code) { uwsgi_log("invalid PSGI status code\n"); return UWSGI_OK;}
 
-        wsgi_req->hvec[0].iov_base = "HTTP/1.1 ";
-        wsgi_req->hvec[0].iov_len = 9;
-
-        wsgi_req->hvec[1].iov_base = SvPV(*status_code, hlen);
-
-        wsgi_req->hvec[1].iov_len = 3;
-
-        wsgi_req->status = atoi(wsgi_req->hvec[1].iov_base);
-
-        wsgi_req->hvec[2].iov_base = " ";
-        wsgi_req->hvec[2].iov_len = 1;
-
-        wsgi_req->hvec[3].iov_len = 0;
-
-        // get the status code
-        for (http_sc = hsc; http_sc->message != NULL; http_sc++) {
-                if (!strncmp(http_sc->key, wsgi_req->hvec[1].iov_base, 3)) {
-                        wsgi_req->hvec[3].iov_base = (char *) http_sc->message;
-                        wsgi_req->hvec[3].iov_len = http_sc->message_size;
-                        break;
-                }
-        }
-
-        if (wsgi_req->hvec[3].iov_len == 0) {
-                wsgi_req->hvec[3].iov_base = "Unknown";
-                wsgi_req->hvec[3].iov_len =  7;
-        }
-
-        wsgi_req->hvec[4].iov_base = "\r\n";
-        wsgi_req->hvec[4].iov_len = 2;
+	char *status_str = SvPV(*status_code, hlen);
+	if (uwsgi_response_prepare_headers(wsgi_req, status_str, hlen)) return UWSGI_OK;
 
         hitem = av_fetch(response, 1, 0);
 	if (!hitem) { uwsgi_log("invalid PSGI headers\n"); return UWSGI_OK;}
@@ -109,65 +81,14 @@ int psgi_response(struct wsgi_request *wsgi_req, AV *response) {
 
         // put them in hvec
         for(i=0; i<=av_len(headers); i++) {
-		if (wsgi_req->header_cnt+1 > uwsgi.max_vars) {
-			uwsgi_log("no more space in iovec. consider increasing max-vars...\n");
-			break;
-		}
                 vi = (i*2)+base;
                 hitem = av_fetch(headers,i,0);
                 chitem = SvPV(*hitem, hlen);
-                wsgi_req->hvec[vi].iov_base = chitem; wsgi_req->hvec[vi].iov_len = hlen;
-
-                wsgi_req->hvec[vi+1].iov_base = ": "; wsgi_req->hvec[vi+1].iov_len = 2;
-
-                hitem = av_fetch(headers,i+1,0);
-                chitem = SvPV(*hitem, hlen);
-                wsgi_req->hvec[vi+2].iov_base = chitem; wsgi_req->hvec[vi+2].iov_len = hlen;
-
-                wsgi_req->hvec[vi+3].iov_base = "\r\n"; wsgi_req->hvec[vi+3].iov_len = 2;
-
-                wsgi_req->header_cnt++;
-
-                i++;
+                hitem2 = av_fetch(headers,i+1,0);
+                chitem2 = SvPV(*hitem, hlen);
+		if (uwsgi_response_add_header(wsgi_req, chitem, hlen, chitem2, hlen)) return UWSGI_OK;
         }
 
-	int j = (i*2)+base;
-	struct uwsgi_string_list *ah = uwsgi.additional_headers;
-        while(ah) {
-		if (wsgi_req->header_cnt+1 > uwsgi.max_vars) {
-			uwsgi_log("no more space in iovec. consider increasing max-vars...\n");
-			break;
-		}
-                wsgi_req->header_cnt++;
-                wsgi_req->hvec[j].iov_base = ah->value;
-                wsgi_req->hvec[j].iov_len = ah->len;
-                j++;
-                wsgi_req->hvec[j].iov_base = "\r\n";
-                wsgi_req->hvec[j].iov_len = 2;
-                j++;
-                ah = ah->next;
- 	}
-
-	ah = wsgi_req->additional_headers;
-	while(ah) {
-                if (wsgi_req->header_cnt+1 > uwsgi.max_vars) {
-                        uwsgi_log("no more space in iovec. consider increasing max-vars...\n");
-                        break;
-                }
-                wsgi_req->header_cnt++;
-                wsgi_req->hvec[j].iov_base = ah->value;
-                wsgi_req->hvec[j].iov_len = ah->len;
-                j++;
-                wsgi_req->hvec[j].iov_base = "\r\n";
-                wsgi_req->hvec[j].iov_len = 2;
-                j++;
-                ah = ah->next;
-        }
-
-        wsgi_req->hvec[j].iov_base = "\r\n"; wsgi_req->hvec[j].iov_len = 2;
-
-        wsgi_req->headers_size += wsgi_req->socket->proto_writev_header(wsgi_req, wsgi_req->hvec, j+1);
-
         hitem = av_fetch(response, 2, 0);
 
 	if (!hitem) {
diff --git a/plugins/python/wsgi_subhandler.c b/plugins/python/wsgi_subhandler.c
index 7c486873..40b414ae 100644
--- a/plugins/python/wsgi_subhandler.c
+++ b/plugins/python/wsgi_subhandler.c
@@ -160,13 +160,9 @@ int uwsgi_response_subhandler_wsgi(struct wsgi_request *wsgi_req) {
 
 	// return or yield ?
 	if (PyString_Check((PyObject *)wsgi_req->async_result)) {
+		char *content = PyString_AsString((PyObject *)wsgi_req->async_result);
 		size_t content_len = PyString_Size((PyObject *)wsgi_req->async_result);
-		if (content_len > 0 && !wsgi_req->headers_sent) {
-			if (uwsgi_python_do_send_headers(wsgi_req)) {
-				goto clear;
-			}
-		}
-		up.hook_write_string(wsgi_req, (PyObject *) wsgi_req->async_result);
+		uwsgi.nb_write_hook(wsgi_req, content, content_len);
 		uwsgi_py_check_write_errors {
 			uwsgi_py_write_exception(wsgi_req);
 		}
diff --git a/proto/fastcgi.c b/proto/fastcgi.c
index b6a98d47..4e6feeb0 100644
--- a/proto/fastcgi.c
+++ b/proto/fastcgi.c
@@ -170,15 +170,12 @@ ssize_t uwsgi_proto_fastcgi_writev(struct wsgi_request * wsgi_req, struct iovec
 	return uwsgi_proto_fastcgi_writev_header(wsgi_req, iovec, iov_len);
 }
 
-ssize_t uwsgi_proto_fastcgi_write(struct wsgi_request * wsgi_req, char *buf, size_t len) {
+int uwsgi_proto_fastcgi_write(struct wsgi_request * wsgi_req, char *buf, size_t len, ssize_t *written) {
 	struct fcgi_record fr;
-	ssize_t rlen;
-	size_t chunk_len;
-	char *ptr = buf;
 
-	// in fastcgi we need to not send 0 size frames
+	// in fastcgi we need to not send 0 sized frames
 	if (!len)
-		return 0;
+		return UWSGI_OK;
 
 	fr.version = 1;
 	fr.type = 6;
@@ -188,9 +185,27 @@ ssize_t uwsgi_proto_fastcgi_write(struct wsgi_request * wsgi_req, char *buf, siz
 	fr.reserved = 0;
 	fr.cl = htons(len);
 
-	// split response in 64k chunks...
+	// still trying to send the fcgi header ?
+	if (*written < 8) {
+		char *ptr = (char *) &fr;
+		ssize_t wlen = write(wsgi_req->poll.fd, ptr + *written, 8 - *written);
+		if (wlen > 0) {
+			*written += wlen;
+			if (*written == 8) {
+				goto body;
+			}
+			return UWSGI_AGAIN;
+		}
+		if (wlen < 0) {
+			if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINPROGRESS) {
+				return UWSGI_AGAIN;
+			}
+		}
+		return -1;
+	}
 
-	if (len <= 65535) {
+	// split response in 64k chunks...
+body:
 		rlen = write(wsgi_req->poll.fd, &fr, 8);
 		if (rlen <= 0) {
 			if (!uwsgi.ignore_write_errors) {
@@ -237,10 +252,6 @@ ssize_t uwsgi_proto_fastcgi_write(struct wsgi_request * wsgi_req, char *buf, siz
 
 }
 
-ssize_t uwsgi_proto_fastcgi_write_header(struct wsgi_request * wsgi_req, char *buf, size_t len) {
-	return uwsgi_proto_fastcgi_write(wsgi_req, buf, len);
-}
-
 void uwsgi_proto_fastcgi_close(struct wsgi_request *wsgi_req) {
 
 	if (write(wsgi_req->poll.fd, FCGI_END_REQUEST, 24) <= 0) {
diff --git a/proto/uwsgi.c b/proto/uwsgi.c
index 129487c5..17047baf 100644
--- a/proto/uwsgi.c
+++ b/proto/uwsgi.c
@@ -116,44 +116,16 @@ int uwsgi_proto_uwsgi_parser(struct wsgi_request *wsgi_req) {
 	return -1;
 }
 
-ssize_t uwsgi_proto_uwsgi_writev_header(struct wsgi_request *wsgi_req, struct iovec * iovec, size_t iov_len) {
-	if (iov_len == 0) return 0;
-	ssize_t wlen = writev(wsgi_req->poll.fd, iovec, iov_len);
-	if (wlen < 0) {
-		if (!uwsgi.ignore_write_errors) {
-			uwsgi_req_error("writev()");
-		}
-		wsgi_req->write_errors++;
-		return 0;
+size_t uwsgi_proto_uwsgi_write(struct wsgi_request * wsgi_req, char *buf, size_t len) {
+	ssize_t wlen = write(wsgi_req->poll.fd, ptr, len);
+	if (wlen > 0) {
+		return wlen;
 	}
-	return wlen;
-}
-
-ssize_t uwsgi_proto_uwsgi_writev(struct wsgi_request *wsgi_req, struct iovec * iovec, size_t iov_len) {
-	return uwsgi_proto_uwsgi_writev_header(wsgi_req, iovec, iov_len);
-}
-
-ssize_t uwsgi_proto_uwsgi_write(struct wsgi_request * wsgi_req, char *buf, size_t len) {
-	ssize_t wlen;
-	char *ptr = buf;
-	if (len == 0) return 0;
-
-	while(len > 0) {
-		wlen = write(wsgi_req->poll.fd, ptr, len);
-		if (wlen <= 0) {
-			if (!uwsgi.ignore_write_errors) {
-				uwsgi_req_error("write()");
-			}
-			wsgi_req->write_errors++;
-			return ptr-buf;
-		}
-		ptr+=wlen;
-		len -= wlen;
+	if (wlen == 0) {
+		return -1;	
 	}
-
-	return ptr-buf;
-}
-
-ssize_t uwsgi_proto_uwsgi_write_header(struct wsgi_request *wsgi_req, char *buf, size_t len) {
-	return uwsgi_proto_uwsgi_write(wsgi_req, buf, len);
+	if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINPROGRESS) {
+		return -2;
+	}
+	return -1;
 }
diff --git a/uwsgi.h b/uwsgi.h
index 3afc1e0b..a619e4dc 100644
--- a/uwsgi.h
+++ b/uwsgi.h
@@ -2073,6 +2073,7 @@ struct uwsgi_server {
 	struct uwsgi_buffer *(*channel_recv_hook)(struct wsgi_request *, int, struct uwsgi_buffer *, int);
 
 	ssize_t (*buffer_write_hook)(struct wsgi_request *, struct uwsgi_buffer *);
+	int (*nb_write_hook)(struct wsgi_request *, char *, size_t);
 
 };
 
diff --git a/uwsgiconfig.py b/uwsgiconfig.py
index e8e7c971..c06c1ce3 100644
--- a/uwsgiconfig.py
+++ b/uwsgiconfig.py
@@ -454,7 +454,7 @@ class uConf(object):
         self.gcc_list = ['core/utils', 'core/protocol', 'core/socket', 'core/logging', 'core/master', 'core/master_utils', 'core/emperor',
             'core/notify', 'core/mule', 'core/subscription', 'core/stats', 'core/sendfile',
             'core/offload', 'core/io', 'core/static', 'core/websockets', 'core/channels',
-            'core/setup_utils', 'core/clock', 'core/init', 'core/buffer',
+            'core/setup_utils', 'core/clock', 'core/init', 'core/buffer', 'core/writer',
             'core/plugins', 'core/lock', 'core/cache', 'core/daemons',
             'core/queue', 'core/event', 'core/signal', 'core/cluster',
             'core/rpc', 'core/gateway', 'core/loop', 'lib/rbtree', 'core/rb_timers', 'core/uwsgi']