diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4711924..39eb2ae 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,13 @@
 # Change Log
 
 
+## 1.1.0 - Unreleased
+
+### Changed
+
+- Allow `psr/http-message` v2 in addition to v1
+- Deprecate all interfaces in favor of [PSR-17](https://www.php-fig.org/psr/psr-17/)
+
 ## 1.0.2 - 2015-12-19
 
 ### Added
diff --git a/composer.json b/composer.json
index 7c72feb..57bdb4b 100644
--- a/composer.json
+++ b/composer.json
@@ -12,7 +12,7 @@
     ],
     "require": {
         "php": ">=5.4",
-        "psr/http-message": "^1.0"
+        "psr/http-message": "^1.0 || ^2.0"
     },
     "autoload": {
         "psr-4": {
@@ -21,7 +21,7 @@
     },
     "extra": {
         "branch-alias": {
-            "dev-master": "1.0-dev"
+            "dev-master": "1.x-dev"
         }
     }
 }
diff --git a/src/MessageFactory.php b/src/MessageFactory.php
index 965aaa8..2ed7e45 100644
--- a/src/MessageFactory.php
+++ b/src/MessageFactory.php
@@ -6,6 +6,8 @@
  * Factory for PSR-7 Request and Response.
  *
  * @author Márk Sági-Kazár <mark.sagikazar@gmail.com>
+ *
+ * @deprecated since version 1.1, use Psr\Http\Message\RequestFactoryInterface and Psr\Http\Message\ResponseFactoryInterface instead.
  */
 interface MessageFactory extends RequestFactory, ResponseFactory
 {
diff --git a/src/RequestFactory.php b/src/RequestFactory.php
index 624e82f..09879f1 100644
--- a/src/RequestFactory.php
+++ b/src/RequestFactory.php
@@ -10,6 +10,8 @@
  * Factory for PSR-7 Request.
  *
  * @author Márk Sági-Kazár <mark.sagikazar@gmail.com>
+ *
+ * @deprecated since version 1.1, use Psr\Http\Message\RequestFactoryInterface instead.
  */
 interface RequestFactory
 {
diff --git a/src/ResponseFactory.php b/src/ResponseFactory.php
index 2411ed3..eb9bde7 100644
--- a/src/ResponseFactory.php
+++ b/src/ResponseFactory.php
@@ -11,6 +11,8 @@
  * This factory contract can be reused in Message and Server Message factories.
  *
  * @author Márk Sági-Kazár <mark.sagikazar@gmail.com>
+ *
+ * @deprecated since version 1.1, use Psr\Http\Message\ResponseFactoryInterface instead.
  */
 interface ResponseFactory
 {
diff --git a/src/StreamFactory.php b/src/StreamFactory.php
index e151389..bd949a4 100644
--- a/src/StreamFactory.php
+++ b/src/StreamFactory.php
@@ -8,6 +8,8 @@
  * Factory for PSR-7 Stream.
  *
  * @author Márk Sági-Kazár <mark.sagikazar@gmail.com>
+ *
+ * @deprecated since version 1.1, use Psr\Http\Message\StreamFactoryInterface instead.
  */
 interface StreamFactory
 {
diff --git a/src/UriFactory.php b/src/UriFactory.php
index e8d8f90..96416b7 100644
--- a/src/UriFactory.php
+++ b/src/UriFactory.php
@@ -8,6 +8,8 @@
  * Factory for PSR-7 URI.
  *
  * @author Márk Sági-Kazár <mark.sagikazar@gmail.com>
+ *
+ * @deprecated since version 1.1, use Psr\Http\Message\UriFactoryInterface instead.
  */
 interface UriFactory
 {