diff --git a/.github/workflows/backward-compatibility.yml b/.github/workflows/backward-compatibility.yml
index 0233e1e422..51e52a365e 100644
--- a/.github/workflows/backward-compatibility.yml
+++ b/.github/workflows/backward-compatibility.yml
@@ -11,9 +11,6 @@ on:
       - 'src/**'
       - '.github/workflows/backward-compatibility.yml'
 
-env:
-  COMPOSER_ROOT_VERSION: "1.12.x-dev"
-
 concurrency:
   group: bc-${{ github.head_ref || github.run_id }} # will be canceled on subsequent pushes in pull requests but not branches
   cancel-in-progress: true
diff --git a/.github/workflows/build-issue-bot.yml b/.github/workflows/build-issue-bot.yml
index 278470b466..06213ad052 100644
--- a/.github/workflows/build-issue-bot.yml
+++ b/.github/workflows/build-issue-bot.yml
@@ -14,9 +14,6 @@ on:
       - 'issue-bot/**'
       - '.github/workflows/build-issue-bot.yml'
 
-env:
-  COMPOSER_ROOT_VERSION: "1.12.x-dev"
-
 concurrency:
   group: build-issue-bot-${{ github.head_ref || github.run_id }} # will be canceled on subsequent pushes in pull requests but not branches
   cancel-in-progress: true
diff --git a/.github/workflows/changelog-generator.yml b/.github/workflows/changelog-generator.yml
index 21971571f3..8084523280 100644
--- a/.github/workflows/changelog-generator.yml
+++ b/.github/workflows/changelog-generator.yml
@@ -14,9 +14,6 @@ on:
       - 'changelog-generator/**'
       - '.github/workflows/changelog-generator.yml'
 
-env:
-  COMPOSER_ROOT_VERSION: "1.12.x-dev"
-
 concurrency:
   group: changelog-${{ github.head_ref || github.run_id }} # will be canceled on subsequent pushes in pull requests but not branches
   cancel-in-progress: true
diff --git a/.github/workflows/checksum-phar.yml b/.github/workflows/checksum-phar.yml
index 47256373d0..fd975528a3 100644
--- a/.github/workflows/checksum-phar.yml
+++ b/.github/workflows/checksum-phar.yml
@@ -17,9 +17,6 @@ on:
       - 'compiler/**'
       - '.github/workflows/checksum-phar.yml'
 
-env:
-  COMPOSER_ROOT_VERSION: "1.12.x-dev"
-
 concurrency:
   group: checksum-phar-${{ github.head_ref || github.run_id }} # will be canceled on subsequent pushes in pull requests but not branches
   cancel-in-progress: true
diff --git a/.github/workflows/e2e-tests.yml b/.github/workflows/e2e-tests.yml
index 53fded3322..c9357fa047 100644
--- a/.github/workflows/e2e-tests.yml
+++ b/.github/workflows/e2e-tests.yml
@@ -18,9 +18,6 @@ on:
       - 'changelog-generator/**'
       - 'issue-bot/**'
 
-env:
-  COMPOSER_ROOT_VERSION: "1.12.x-dev"
-
 concurrency:
   group: e2e-${{ github.head_ref || github.run_id }} # will be canceled on subsequent pushes in pull requests but not branches
   cancel-in-progress: true
diff --git a/.github/workflows/issue-bot.yml b/.github/workflows/issue-bot.yml
index 5ef4bd6275..6d6af362f1 100644
--- a/.github/workflows/issue-bot.yml
+++ b/.github/workflows/issue-bot.yml
@@ -17,9 +17,6 @@ on:
       - 'apigen/**'
       - 'changelog-generator/**'
 
-env:
-  COMPOSER_ROOT_VERSION: "1.12.x-dev"
-
 concurrency:
   group: run-issue-bot-${{ github.head_ref || github.run_id }} # will be canceled on subsequent pushes in pull requests but not branches
   cancel-in-progress: true
diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 03420615cd..afc5c0db7c 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -8,9 +8,6 @@ on:
     branches:
       - "1.12.x"
 
-env:
-  COMPOSER_ROOT_VERSION: "1.12.x-dev"
-
 concurrency:
   group: lint-${{ github.head_ref || github.run_id }} # will be canceled on subsequent pushes in pull requests but not branches
   cancel-in-progress: true
diff --git a/.github/workflows/reflection-golden-test.yml b/.github/workflows/reflection-golden-test.yml
index 6d16f21aaa..8b84920a73 100644
--- a/.github/workflows/reflection-golden-test.yml
+++ b/.github/workflows/reflection-golden-test.yml
@@ -19,7 +19,6 @@ on:
       - 'issue-bot/**'
 
 env:
-  COMPOSER_ROOT_VERSION: "1.12.x-dev"
   REFLECTION_GOLDEN_TEST_FILE: "/tmp/reflection-golden.test"
   REFLECTION_GOLDEN_SYMBOLS_FILE: "/tmp/reflection-golden-symbols.txt"
 
diff --git a/.github/workflows/static-analysis.yml b/.github/workflows/static-analysis.yml
index b19b6c10f7..e8b9e1ec39 100644
--- a/.github/workflows/static-analysis.yml
+++ b/.github/workflows/static-analysis.yml
@@ -14,9 +14,6 @@ on:
       - 'compiler/**'
       - 'apigen/**'
 
-env:
-  COMPOSER_ROOT_VERSION: "1.12.x-dev"
-
 concurrency:
   group: sa-${{ github.head_ref || github.run_id }} # will be canceled on subsequent pushes in pull requests but not branches
   cancel-in-progress: true
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 59d834e9c7..292f8ccf27 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -18,9 +18,6 @@ on:
       - 'changelog-generator/**'
       - 'issue-bot/**'
 
-env:
-  COMPOSER_ROOT_VERSION: "1.12.x-dev"
-
 concurrency:
   group: tests-${{ github.head_ref || github.run_id }} # will be canceled on subsequent pushes in pull requests but not branches
   cancel-in-progress: true
diff --git a/README.md b/README.md
index 6d2e16963c..e817604542 100644
--- a/README.md
+++ b/README.md
@@ -17,8 +17,6 @@ Any contributions are welcome.
 composer install
 ```
 
-If you encounter dependency problem, try using `export COMPOSER_ROOT_VERSION=1.11.x-dev`
-
 If you are using macOS and are using an older version of `patch`, you may have problems with patch application failure during `composer install`. Try using `brew install gpatch` to install a newer and supported `patch` version.
 
 ### Building
diff --git a/composer.json b/composer.json
index 02ef955af2..eb0fc3b709 100644
--- a/composer.json
+++ b/composer.json
@@ -50,7 +50,7 @@
 		"symfony/string": "^5.4.3"
 	},
 	"replace": {
-		"phpstan/phpstan": "self.version"
+		"phpstan/phpstan": "1.12.x"
 	},
 	"require-dev": {
 		"brianium/paratest": "^6.5",
diff --git a/composer.lock b/composer.lock
index a72a0e69ef..0b88dc696a 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": "9cb259d4d2ef11aad375ee55188ab4d3",
+    "content-hash": "b4ef5f2e88180f1e71abe684e35b9759",
     "packages": [
         {
             "name": "clue/ndjson-react",