diff --git a/.travis.yml b/.travis.yml
index 0789302..6058d0e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,23 +1,23 @@
 language: dart
 
 dart:
- - dev
+ - preview/raw/2.10.0-0.2-dev
 
 jobs:
   include:
     - stage: analyze_and_format
       name: "Analyzer"
-      dart: be/raw/latest
+      dart: preview/raw/2.10.0-0.2-dev
       os: linux
       script: dartanalyzer --enable-experiment=non-nullable --fatal-warnings --fatal-infos .
     - stage: analyze_and_format
       name: "Format"
-      dart: be/raw/latest
+      dart: preview/raw/2.10.0-0.2-dev
       os: linux
       script: dartfmt -n --set-exit-if-changed .
     - stage: test
       name: "Vm Tests"
-      dart: be/raw/latest
+      dart: preview/raw/2.10.0-0.2-dev
       os: linux
       script: pub run --enable-experiment=non-nullable test -p vm
 
@@ -27,7 +27,7 @@
 
 # Only building master means that we don't run two builds for each pull request.
 branches:
-  only: [master, null_safety]
+  only: [master]
 
 cache:
   directories:
diff --git a/pubspec.yaml b/pubspec.yaml
index b8b410e..dee5b39 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -5,83 +5,62 @@
 homepage: https://www.github.com/dart-lang/async
 
 environment:
-  sdk: '>=2.9.0-20.0.dev <2.9.0'
+  # This must remain a tight constraint until nnbd is stable
+  sdk: '>=2.10.0-0 <2.10.0'
 
 dependencies:
   collection: '>=1.15.0-nullsafety <1.15.0'
 
-dev_dependencies:
-  fake_async: ^1.0.0
-  stack_trace: ^1.0.0
-  test: ^1.0.0
-  pedantic: ^1.0.0
-
 dependency_overrides:
   boolean_selector:
-    git:
-      url: git://github.com/dart-lang/boolean_selector.git
-      ref: null_safety
+    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/charcode.git
-      ref: null_safety
-  clock:
-    git:
-      url: git://github.com/dart-lang/clock.git
-      ref: null_safety
-  fake_async:
-    git:
-      url: git://github.com/dart-lang/fake_async.git
-      ref: null_safety
+      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/matcher.git
-      ref: null_safety
-  meta: '>=1.3.0-nullsafety <1.3.0'
+      url: git://github.com/dart-lang/sdk.git
+      path: pkg/meta
+      ref: 2-10-pkgs
   path:
-    git:
-      url: git://github.com/dart-lang/path.git
-      ref: null_safety
+    git: git://github.com/dart-lang/path.git
   pedantic:
-    git:
-      url: git://github.com/dart-lang/pedantic.git
-      ref: null_safety
+    git: git://github.com/dart-lang/pedantic.git
   pool:
-    git:
-      url: git://github.com/dart-lang/pool.git
-      ref: null_safety
+    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:
-      url: git://github.com/dart-lang/source_span.git
-      ref: null_safety
+    git: git://github.com/dart-lang/source_span.git
   stack_trace:
-    git:
-      url: git://github.com/dart-lang/stack_trace.git
-      ref: null_safety
+    git: git://github.com/dart-lang/stack_trace.git
   stream_channel:
-    git:
-      url: git://github.com/dart-lang/stream_channel.git
-      ref: null_safety
+    git: git://github.com/dart-lang/stream_channel.git
   string_scanner:
-    git:
-      url: git://github.com/dart-lang/string_scanner.git
-      ref: null_safety
+    git: git://github.com/dart-lang/string_scanner.git
   term_glyph:
-    git:
-      url: git://github.com/dart-lang/term_glyph.git
-      ref: null_safety
+    git: git://github.com/dart-lang/term_glyph.git
   test_api:
     git:
       url: git://github.com/dart-lang/test.git
-      ref: null_safety
       path: pkgs/test_api
   test_core:
     git:
       url: git://github.com/dart-lang/test.git
-      ref: null_safety
       path: pkgs/test_core
   test:
     git:
       url: git://github.com/dart-lang/test.git
-      ref: null_safety
       path: pkgs/test
+  typed_data:
+    git: git://github.com/dart-lang/typed_data.git