new file mode 100644
--- /dev/null
+++ b/src/stream/ngx_stream_quic_module.c
@@ -0,0 +1,343 @@
+
+/*
+ * Copyright (C) Nginx, Inc.
+ * Copyright (C) Roman Arutyunyan
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_stream.h>
+
+
+static ngx_int_t ngx_stream_variable_quic(ngx_stream_session_t *s,
+    ngx_stream_variable_value_t *v, uintptr_t data);
+static ngx_int_t ngx_stream_quic_add_variables(ngx_conf_t *cf);
+static void *ngx_stream_quic_create_srv_conf(ngx_conf_t *cf);
+static char *ngx_stream_quic_merge_srv_conf(ngx_conf_t *cf, void *parent,
+    void *child);
+static char *ngx_stream_quic_max_ack_delay(ngx_conf_t *cf, void *post,
+    void *data);
+static char *ngx_stream_quic_max_udp_payload_size(ngx_conf_t *cf, void *post,
+    void *data);
+
+
+static ngx_conf_post_t  ngx_stream_quic_max_ack_delay_post =
+    { ngx_stream_quic_max_ack_delay };
+static ngx_conf_post_t  ngx_stream_quic_max_udp_payload_size_post =
+    { ngx_stream_quic_max_udp_payload_size };
+static ngx_conf_num_bounds_t  ngx_stream_quic_ack_delay_exponent_bounds =
+    { ngx_conf_check_num_bounds, 0, 20 };
+static ngx_conf_num_bounds_t 
+                            ngx_stream_quic_active_connection_id_limit_bounds =
+    { ngx_conf_check_num_bounds, 2, -1 };
+
+
+static ngx_command_t  ngx_stream_quic_commands[] = {
+
+    { ngx_string("quic_max_idle_timeout"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_msec_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, tp.max_idle_timeout),
+      NULL },
+
+    { ngx_string("quic_max_ack_delay"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_msec_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, tp.max_ack_delay),
+      &ngx_stream_quic_max_ack_delay_post },
+
+    { ngx_string("quic_max_udp_payload_size"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_size_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, tp.max_udp_payload_size),
+      &ngx_stream_quic_max_udp_payload_size_post },
+
+    { ngx_string("quic_initial_max_data"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_size_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, tp.initial_max_data),
+      NULL },
+
+    { ngx_string("quic_initial_max_stream_data_bidi_local"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_size_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, tp.initial_max_stream_data_bidi_local),
+      NULL },
+
+    { ngx_string("quic_initial_max_stream_data_bidi_remote"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_size_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, tp.initial_max_stream_data_bidi_remote),
+      NULL },
+
+    { ngx_string("quic_initial_max_stream_data_uni"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_size_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, tp.initial_max_stream_data_uni),
+      NULL },
+
+    { ngx_string("quic_initial_max_streams_bidi"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_num_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, tp.initial_max_streams_bidi),
+      NULL },
+
+    { ngx_string("quic_initial_max_streams_uni"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_num_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, tp.initial_max_streams_uni),
+      NULL },
+
+    { ngx_string("quic_ack_delay_exponent"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_num_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, tp.ack_delay_exponent),
+      &ngx_stream_quic_ack_delay_exponent_bounds },
+
+    { ngx_string("quic_active_migration"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_num_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, tp.disable_active_migration),
+      NULL },
+
+    { ngx_string("quic_active_connection_id_limit"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_num_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, tp.active_connection_id_limit),
+      &ngx_stream_quic_active_connection_id_limit_bounds },
+
+    { ngx_string("quic_retry"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_FLAG,
+      ngx_conf_set_flag_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_quic_conf_t, retry),
+      NULL },
+
+      ngx_null_command
+};
+
+
+static ngx_stream_module_t  ngx_stream_quic_module_ctx = {
+    ngx_stream_quic_add_variables,         /* preconfiguration */
+    NULL,                                  /* postconfiguration */
+
+    NULL,                                  /* create main configuration */
+    NULL,                                  /* init main configuration */
+
+    ngx_stream_quic_create_srv_conf,       /* create server configuration */
+    ngx_stream_quic_merge_srv_conf,        /* merge server configuration */
+};
+
+
+ngx_module_t  ngx_stream_quic_module = {
+    NGX_MODULE_V1,
+    &ngx_stream_quic_module_ctx,           /* module context */
+    ngx_stream_quic_commands,              /* module directives */
+    NGX_STREAM_MODULE,                     /* module type */
+    NULL,                                  /* init master */
+    NULL,                                  /* init module */
+    NULL,                                  /* init process */
+    NULL,                                  /* init thread */
+    NULL,                                  /* exit thread */
+    NULL,                                  /* exit process */
+    NULL,                                  /* exit master */
+    NGX_MODULE_V1_PADDING
+};
+
+
+static ngx_stream_variable_t  ngx_stream_quic_vars[] = {
+
+    { ngx_string("quic"), NULL, ngx_stream_variable_quic, 0, 0, 0 },
+
+      ngx_stream_null_variable
+};
+
+
+static ngx_int_t
+ngx_stream_variable_quic(ngx_stream_session_t *s,
+    ngx_stream_variable_value_t *v, uintptr_t data)
+{
+    if (s->connection->qs) {
+
+        v->len = 4;
+        v->valid = 1;
+        v->no_cacheable = 1;
+        v->not_found = 0;
+        v->data = (u_char *) "quic";
+        return NGX_OK;
+    }
+
+    v->not_found = 1;
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_stream_quic_add_variables(ngx_conf_t *cf)
+{
+    ngx_stream_variable_t  *var, *v;
+
+    for (v = ngx_stream_quic_vars; v->name.len; v++) {
+        var = ngx_stream_add_variable(cf, &v->name, v->flags);
+        if (var == NULL) {
+            return NGX_ERROR;
+        }
+
+        var->get_handler = v->get_handler;
+        var->data = v->data;
+    }
+
+    return NGX_OK;
+}
+
+
+static void *
+ngx_stream_quic_create_srv_conf(ngx_conf_t *cf)
+{
+    ngx_quic_conf_t  *conf;
+
+    conf = ngx_pcalloc(cf->pool, sizeof(ngx_quic_conf_t));
+    if (conf == NULL) {
+        return NULL;
+    }
+
+    /*
+     * set by ngx_pcalloc():
+     *
+     *     conf->tp.original_dcid = { 0, NULL };
+     *     conf->tp.initial_scid = { 0, NULL };
+     *     conf->tp.retry_scid = { 0, NULL };
+     *     conf->tp.stateless_reset_token = { 0 }
+     *     conf->tp.preferred_address = NULL
+     *     conf->require_alpn = 0;
+     */
+
+    conf->tp.max_idle_timeout = NGX_CONF_UNSET_MSEC;
+    conf->tp.max_ack_delay = NGX_CONF_UNSET_MSEC;
+    conf->tp.max_udp_payload_size = NGX_CONF_UNSET_SIZE;
+    conf->tp.initial_max_data = NGX_CONF_UNSET_SIZE;
+    conf->tp.initial_max_stream_data_bidi_local = NGX_CONF_UNSET_SIZE;
+    conf->tp.initial_max_stream_data_bidi_remote = NGX_CONF_UNSET_SIZE;
+    conf->tp.initial_max_stream_data_uni = NGX_CONF_UNSET_SIZE;
+    conf->tp.initial_max_streams_bidi = NGX_CONF_UNSET_UINT;
+    conf->tp.initial_max_streams_uni = NGX_CONF_UNSET_UINT;
+    conf->tp.ack_delay_exponent = NGX_CONF_UNSET_UINT;
+    conf->tp.disable_active_migration = NGX_CONF_UNSET_UINT;
+    conf->tp.active_connection_id_limit = NGX_CONF_UNSET_UINT;
+
+    conf->retry = NGX_CONF_UNSET;
+
+    return conf;
+}
+
+
+static char *
+ngx_stream_quic_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child)
+{
+    ngx_quic_conf_t *prev = parent;
+    ngx_quic_conf_t *conf = child;
+
+    ngx_conf_merge_msec_value(conf->tp.max_idle_timeout,
+                              prev->tp.max_idle_timeout, 60000);
+
+    ngx_conf_merge_msec_value(conf->tp.max_ack_delay,
+                              prev->tp.max_ack_delay,
+                              NGX_QUIC_DEFAULT_MAX_ACK_DELAY);
+
+    ngx_conf_merge_size_value(conf->tp.max_udp_payload_size,
+                              prev->tp.max_udp_payload_size,
+                              NGX_QUIC_MAX_UDP_PAYLOAD_SIZE);
+
+    ngx_conf_merge_size_value(conf->tp.initial_max_data,
+                              prev->tp.initial_max_data,
+                              16 * NGX_QUIC_STREAM_BUFSIZE);
+
+    ngx_conf_merge_size_value(conf->tp.initial_max_stream_data_bidi_local,
+                              prev->tp.initial_max_stream_data_bidi_local,
+                              NGX_QUIC_STREAM_BUFSIZE);
+
+    ngx_conf_merge_size_value(conf->tp.initial_max_stream_data_bidi_remote,
+                              prev->tp.initial_max_stream_data_bidi_remote,
+                              NGX_QUIC_STREAM_BUFSIZE);
+
+    ngx_conf_merge_size_value(conf->tp.initial_max_stream_data_uni,
+                              prev->tp.initial_max_stream_data_uni,
+                              NGX_QUIC_STREAM_BUFSIZE);
+
+    ngx_conf_merge_uint_value(conf->tp.initial_max_streams_bidi,
+                              prev->tp.initial_max_streams_bidi, 16);
+
+    ngx_conf_merge_uint_value(conf->tp.initial_max_streams_uni,
+                              prev->tp.initial_max_streams_uni, 16);
+
+    ngx_conf_merge_uint_value(conf->tp.ack_delay_exponent,
+                              prev->tp.ack_delay_exponent,
+                              NGX_QUIC_DEFAULT_ACK_DELAY_EXPONENT);
+
+    ngx_conf_merge_uint_value(conf->tp.disable_active_migration,
+                              prev->tp.disable_active_migration, 1);
+
+    ngx_conf_merge_uint_value(conf->tp.active_connection_id_limit,
+                              prev->tp.active_connection_id_limit, 2);
+
+    ngx_conf_merge_value(conf->retry, prev->retry, 0);
+
+    if (conf->retry) {
+        if (RAND_bytes(conf->token_key, sizeof(conf->token_key)) <= 0) {
+            return NGX_CONF_ERROR;
+        }
+    }
+
+    return NGX_CONF_OK;
+}
+
+
+static char *
+ngx_stream_quic_max_ack_delay(ngx_conf_t *cf, void *post, void *data)
+{
+    ngx_msec_t *sp = data;
+
+    if (*sp > 16384) {
+        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                           "\"quic_max_ack_delay\" must be less than 16384");
+
+        return NGX_CONF_ERROR;
+    }
+
+    return NGX_CONF_OK;
+}
+
+
+static char *
+ngx_stream_quic_max_udp_payload_size(ngx_conf_t *cf, void *post, void *data)
+{
+    size_t *sp = data;
+
+    if (*sp < NGX_QUIC_MIN_INITIAL_SIZE
+        || *sp > NGX_QUIC_MAX_UDP_PAYLOAD_SIZE)
+    {
+        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                           "\"quic_max_udp_payload_size\" must be between "
+                           "%d and %d",
+                           NGX_QUIC_MIN_INITIAL_SIZE,
+                           NGX_QUIC_MAX_UDP_PAYLOAD_SIZE);
+
+        return NGX_CONF_ERROR;
+    }
+
+    return NGX_CONF_OK;
+}