stable version (#176)

diff --git a/packages/file/CHANGELOG.md b/packages/file/CHANGELOG.md
index 62bc35f..a8a9547 100644
--- a/packages/file/CHANGELOG.md
+++ b/packages/file/CHANGELOG.md
@@ -1,3 +1,7 @@
+#### 6.0.0
+
+* First stable null safe release.
+
 #### 6.0.0-nullsafety.4
 
 * Update upper bound of SDK constraint.
diff --git a/packages/file/lib/src/backends/chroot/chroot_random_access_file.dart b/packages/file/lib/src/backends/chroot/chroot_random_access_file.dart
index 968c2c2..4105ac8 100644
--- a/packages/file/lib/src/backends/chroot/chroot_random_access_file.dart
+++ b/packages/file/lib/src/backends/chroot/chroot_random_access_file.dart
@@ -2,7 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart=2.10
 part of file.src.backends.chroot;
 
 class _ChrootRandomAccessFile with ForwardingRandomAccessFile {
diff --git a/packages/file/pubspec.yaml b/packages/file/pubspec.yaml
index 435c714..d5c9987 100644
--- a/packages/file/pubspec.yaml
+++ b/packages/file/pubspec.yaml
@@ -1,5 +1,5 @@
 name: file
-version: 6.0.0-nullsafety.4
+version: 6.0.0
 description:
   A pluggable, mockable file system abstraction for Dart. Supports local file
   system access, as well as in-memory file systems, record-replay file systems,
@@ -10,8 +10,7 @@
   sdk: '>=2.12.0-0 <3.0.0'
 
 dependencies:
-  meta: ^1.3.0-nullsafety.6
-  path: ^1.8.0-nullsafety.3
+  path: ^1.8.0
 
 dev_dependencies:
   file_testing: '>=2.0.0 <3.0.0'