diff --git a/composer.json b/composer.json
index 29f05ed2..c4bf1081 100644
--- a/composer.json
+++ b/composer.json
@@ -38,7 +38,7 @@
     "phpunit/phpunit": "^7.5.20",
     "psalm/plugin-phpunit": "~0.10.0",
     "symfony/filesystem": "^4.4.7",
-    "vimeo/psalm": "^3.10.1"
+    "vimeo/psalm": "^3.11.0"
   },
   "config": {
     "platform": {
diff --git a/composer.lock b/composer.lock
index 2aebfb49..6f68d2bd 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "8d7fa009417381715af8757b1f4aab41",
+    "content-hash": "97ad6c5b3cc8aaf1cc0d1cd6252be005",
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             "name": "ergebnis/json-normalizer",
@@ -243,16 +243,16 @@
     "packages-dev": [
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-            "version": "v2.4.1",
+            "version": "v2.4.2",
             "source": {
                 "type": "git",
                 "url": "https://github.com/amphp/amp.git",
-                "reference": "2ac3b550c4997f2ec304faa63c8b2885079a2dc4"
+                "reference": "feca077369a47263b22156b3c6389e55f3809f24"
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-                "url": "https://api.github.com/repos/amphp/amp/zipball/2ac3b550c4997f2ec304faa63c8b2885079a2dc4",
-                "reference": "2ac3b550c4997f2ec304faa63c8b2885079a2dc4",
+                "url": "https://api.github.com/repos/amphp/amp/zipball/feca077369a47263b22156b3c6389e55f3809f24",
+                "reference": "feca077369a47263b22156b3c6389e55f3809f24",
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@@ -262,14 +262,15 @@
                 "amphp/php-cs-fixer-config": "dev-master",
                 "amphp/phpunit-util": "^1",
                 "ext-json": "*",
-                "phpstan/phpstan": "^0.8.5",
+                "jetbrains/phpstorm-stubs": "^2019.3",
                 "phpunit/phpunit": "^6.0.9 | ^7",
-                "react/promise": "^2"
+                "react/promise": "^2",
+                "vimeo/psalm": "^3.9@dev"
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "2.0.x-dev"
+                    "dev-master": "2.x-dev"
                 }
             },
             "autoload": {
@@ -316,20 +317,20 @@
                 "non-blocking",
                 "promise"
             ],
-            "time": "2020-02-10T18:10:57+00:00"
+            "time": "2020-04-04T15:05:26+00:00"
         },
         {
             "name": "amphp/byte-stream",
-            "version": "v1.7.2",
+            "version": "v1.7.3",
             "source": {
                 "type": "git",
                 "url": "https://github.com/amphp/byte-stream.git",
-                "reference": "1e52f1752b2e20e2a7e464476ef887a2388e3832"
+                "reference": "b867505edb79dda8f253ca3c3a2bbadae4b16592"
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-                "url": "https://api.github.com/repos/amphp/byte-stream/zipball/1e52f1752b2e20e2a7e464476ef887a2388e3832",
-                "reference": "1e52f1752b2e20e2a7e464476ef887a2388e3832",
+                "url": "https://api.github.com/repos/amphp/byte-stream/zipball/b867505edb79dda8f253ca3c3a2bbadae4b16592",
+                "reference": "b867505edb79dda8f253ca3c3a2bbadae4b16592",
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@@ -339,10 +340,16 @@
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                 "friendsofphp/php-cs-fixer": "^2.3",
-                "infection/infection": "^0.9.3",
-                "phpunit/phpunit": "^6"
+                "jetbrains/phpstorm-stubs": "^2019.3",
+                "phpunit/phpunit": "^6 || ^7 || ^8",
+                "vimeo/psalm": "^3.9@dev"
             },
             "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.x-dev"
+                }
+            },
             "autoload": {
                 "psr-4": {
                     "Amp\\ByteStream\\": "lib"
@@ -375,7 +382,7 @@
                 "non-blocking",
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-            "time": "2020-01-29T18:22:23+00:00"
+            "time": "2020-04-04T16:56:54+00:00"
         },
         {
             "name": "composer/ca-bundle",
@@ -1498,16 +1505,16 @@
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             "name": "netresearch/jsonmapper",
-            "version": "v1.6.0",
+            "version": "v2.0.0",
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                 "type": "git",
                 "url": "https://github.com/cweiske/jsonmapper.git",
-                "reference": "0d4d1b48d682a93b6bfedf60b88c7750e9cb0b06"
+                "reference": "e245890383c3ed38b6d202ee373c23ccfebc0f54"
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-                "reference": "0d4d1b48d682a93b6bfedf60b88c7750e9cb0b06",
+                "url": "https://api.github.com/repos/cweiske/jsonmapper/zipball/e245890383c3ed38b6d202ee373c23ccfebc0f54",
+                "reference": "e245890383c3ed38b6d202ee373c23ccfebc0f54",
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@@ -1518,8 +1525,8 @@
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             "require-dev": {
-                "phpunit/phpunit": "~4.8.35 || ~5.7 || ~6.4",
-                "squizlabs/php_codesniffer": "~1.5"
+                "phpunit/phpunit": "~4.8.35 || ~5.7 || ~6.4 || ~7.0",
+                "squizlabs/php_codesniffer": "~3.5"
             },
             "type": "library",
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@@ -1540,20 +1547,20 @@
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             ],
             "description": "Map nested JSON structures onto PHP classes",
-            "time": "2019-08-15T19:41:25+00:00"
+            "time": "2020-03-04T17:23:33+00:00"
         },
         {
             "name": "nikic/php-parser",
-            "version": "v4.3.0",
+            "version": "v4.4.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/nikic/PHP-Parser.git",
-                "reference": "9a9981c347c5c49d6dfe5cf826bb882b824080dc"
+                "reference": "bd43ec7152eaaab3bd8c6d0aa95ceeb1df8ee120"
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-                "reference": "9a9981c347c5c49d6dfe5cf826bb882b824080dc",
+                "url": "https://api.github.com/repos/nikic/PHP-Parser/zipball/bd43ec7152eaaab3bd8c6d0aa95ceeb1df8ee120",
+                "reference": "bd43ec7152eaaab3bd8c6d0aa95ceeb1df8ee120",
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             "require": {
@@ -1592,7 +1599,7 @@
                 "parser",
                 "php"
             ],
-            "time": "2019-11-08T13:50:10+00:00"
+            "time": "2020-04-10T16:34:50+00:00"
         },
         {
             "name": "ocramius/package-versions",
@@ -4334,16 +4341,16 @@
         },
         {
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-            "version": "3.10.1",
+            "version": "3.11.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/vimeo/psalm.git",
-                "reference": "eeed5ecccc10131397f0eb7ee6da810c0be3a7fc"
+                "reference": "5bc9b095d1a6f1a2e0890353fc2c6cd7de62371d"
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             "dist": {
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-                "reference": "eeed5ecccc10131397f0eb7ee6da810c0be3a7fc",
+                "url": "https://api.github.com/repos/vimeo/psalm/zipball/5bc9b095d1a6f1a2e0890353fc2c6cd7de62371d",
+                "reference": "5bc9b095d1a6f1a2e0890353fc2c6cd7de62371d",
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@@ -4358,7 +4365,7 @@
                 "ext-tokenizer": "*",
                 "felixfbecker/advanced-json-rpc": "^3.0.3",
                 "felixfbecker/language-server-protocol": "^1.4",
-                "netresearch/jsonmapper": "^1.0",
+                "netresearch/jsonmapper": "^1.0 || ^2.0",
                 "nikic/php-parser": "^4.3",
                 "ocramius/package-versions": "^1.2",
                 "openlss/lib-array2xml": "^1.0",
@@ -4372,13 +4379,15 @@
                 "psalm/psalm": "self.version"
             },
             "require-dev": {
+                "amphp/amp": "^2.4.2",
                 "bamarni/composer-bin-plugin": "^1.2",
                 "brianium/paratest": "^4.0.0",
                 "ext-curl": "*",
+                "php-coveralls/php-coveralls": "^2.2",
                 "phpmyadmin/sql-parser": "5.1.0",
                 "phpspec/prophecy": ">=1.9.0",
-                "phpunit/phpunit": "^7.5.16 || ^8.5",
-                "psalm/plugin-phpunit": "^0.9",
+                "phpunit/phpunit": "^7.5.16 || ^8.5 || ^9.0",
+                "psalm/plugin-phpunit": "^0.10",
                 "slevomat/coding-standard": "^5.0",
                 "squizlabs/php_codesniffer": "^3.5",
                 "symfony/process": "^4.3"
@@ -4426,7 +4435,7 @@
                 "inspection",
                 "php"
             ],
-            "time": "2020-03-23T11:40:30+00:00"
+            "time": "2020-04-12T18:43:12+00:00"
         },
         {
             "name": "webmozart/assert",