diff --git a/build.yaml b/build.yaml
deleted file mode 100644
index 340d63c..0000000
--- a/build.yaml
+++ /dev/null
@@ -1,13 +0,0 @@
-# See https://github.com/dart-lang/build/tree/master/build_web_compilers#configuration
-# Matches previous configuration in pubspec.yaml - transformers - $dart2js
-targets:
-  $default:
-    builders:
-      build_web_compilers|entrypoint:
-        # These are globs for the entrypoints you want to compile.
-        generate_for:
-          include:
-          - test/**.dart
-          exclude:
-          - test/io_test.dart
-          - test/**vm_test.dart
diff --git a/pubspec.yaml b/pubspec.yaml
index 3b1aafa..59aa99e 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -12,63 +12,5 @@
   sdk: '>=2.10.0-0 <2.11.0'
 
 dev_dependencies:
-  pedantic: ^1.0.0
-  test: '>=0.12.42 <2.0.0'
-
-  build_runner: ^1.0.0
-  build_test: ^0.10.0
-  build_web_compilers: '>=1.2.0 <3.0.0'
-
-dependency_overrides:
-  async:
-    git: git://github.com/dart-lang/async.git
-  boolean_selector:
-    git: git://github.com/dart-lang/boolean_selector.git
-  charcode:
-    git: git://github.com/dart-lang/charcode.git
-  collection:
-    git: git://github.com/dart-lang/collection.git
-  js:
-    git:
-      url: git://github.com/dart-lang/sdk.git
-      path: pkg/js
-      ref: 2-10-pkgs
-  matcher:
-    git: git://github.com/dart-lang/matcher.git
-  meta:
-    git:
-      url: git://github.com/dart-lang/sdk.git
-      path: pkg/meta
-      ref: 2-10-pkgs
-  pedantic:
-    git: git://github.com/dart-lang/pedantic.git
-  pool:
-    git: git://github.com/dart-lang/pool.git
-  source_maps:
-    git: git://github.com/dart-lang/source_maps.git
-  source_map_stack_trace:
-    git: git://github.com/dart-lang/source_map_stack_trace.git
-  source_span:
-    git: git://github.com/dart-lang/source_span.git
-  stack_trace:
-    git: git://github.com/dart-lang/stack_trace.git
-  stream_channel:
-    git: git://github.com/dart-lang/stream_channel.git
-  string_scanner:
-    git: git://github.com/dart-lang/string_scanner.git
-  term_glyph:
-    git: git://github.com/dart-lang/term_glyph.git
-  test_api:
-    git:
-      url: git://github.com/dart-lang/test.git
-      path: pkgs/test_api
-  test_core:
-    git:
-      url: git://github.com/dart-lang/test.git
-      path: pkgs/test_core
-  test:
-    git:
-      url: git://github.com/dart-lang/test.git
-      path: pkgs/test
-  typed_data:
-    git: git://github.com/dart-lang/typed_data.git
+  pedantic: ^1.10.0-nullsafety
+  test: ^1.16.0-nullsafety.4