diff --git a/CHANGELOG.md b/CHANGELOG.md
index b253b1112b..167260a267 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,7 +1,14 @@
-# 0.50.1
+# 0.52.1
+
+- Check for single instances for api and types as they are loaded (assertSingletonPackage)
+
+# 0.51.1
 
 - Support metadata V2 as per latest substrate master
 - Update metadata with new types as per lastest substrate master
+
+# 0.50.1
+
 - Lastest util-crypto (usage of WASM with JS fallbacks if not available)
 - Update upstream @polkadot dependencies (for new crypto)
 
diff --git a/packages/api/package.json b/packages/api/package.json
index cc228c0534..e7fc2630f2 100644
--- a/packages/api/package.json
+++ b/packages/api/package.json
@@ -36,6 +36,6 @@
     "@polkadot/rpc-rx": "^0.51.1",
     "@polkadot/storage": "^0.51.1",
     "@polkadot/types": "^0.51.1",
-    "@polkadot/util-crypto": "^0.41.1"
+    "@polkadot/util-crypto": "^0.42.0-beta.0"
   }
 }
diff --git a/packages/api/src/index.ts b/packages/api/src/index.ts
index 09e8451e43..54dd9e61e4 100644
--- a/packages/api/src/index.ts
+++ b/packages/api/src/index.ts
@@ -3,6 +3,9 @@
 // of the Apache-2.0 license. See the LICENSE file for details.
 
 export { WsProvider } from '@polkadot/rpc-provider';
+import { assertSingletonPackage } from '@polkadot/util';
+
+assertSingletonPackage('@polkadot/api');
 
 export { default as ApiPromise } from './promise';
 export { default as ApiRx } from './rx';
diff --git a/packages/rpc-core/package.json b/packages/rpc-core/package.json
index 48b56e9da3..b1aa6c27cb 100644
--- a/packages/rpc-core/package.json
+++ b/packages/rpc-core/package.json
@@ -33,6 +33,6 @@
     "@polkadot/jsonrpc": "^0.51.1",
     "@polkadot/rpc-provider": "^0.51.1",
     "@polkadot/types": "^0.51.1",
-    "@polkadot/util": "^0.41.1"
+    "@polkadot/util": "^0.42.0-beta.0"
   }
 }
diff --git a/packages/rpc-provider/package.json b/packages/rpc-provider/package.json
index 4abbf840b6..2055060217 100644
--- a/packages/rpc-provider/package.json
+++ b/packages/rpc-provider/package.json
@@ -30,10 +30,10 @@
   "homepage": "https://github.com/polkadot-js/api/tree/master/packages/rpc-provider#readme",
   "dependencies": {
     "@babel/runtime": "^7.4.0",
-    "@polkadot/keyring": "^0.41.1",
+    "@polkadot/keyring": "^0.42.0-beta.0",
     "@polkadot/storage": "^0.51.1",
-    "@polkadot/util": "^0.41.1",
-    "@polkadot/util-crypto": "^0.41.1",
+    "@polkadot/util": "^0.42.0-beta.0",
+    "@polkadot/util-crypto": "^0.42.0-beta.0",
     "@types/nock": "^9.3.1",
     "eventemitter3": "^3.1.0",
     "isomorphic-fetch": "^2.2.1",
diff --git a/packages/type-extrinsics/package.json b/packages/type-extrinsics/package.json
index d3321b33c3..828713eab1 100644
--- a/packages/type-extrinsics/package.json
+++ b/packages/type-extrinsics/package.json
@@ -12,6 +12,6 @@
   "dependencies": {
     "@babel/runtime": "^7.4.0",
     "@polkadot/types": "^0.51.1",
-    "@polkadot/util": "^0.41.1"
+    "@polkadot/util": "^0.42.0-beta.0"
   }
 }
diff --git a/packages/type-storage/package.json b/packages/type-storage/package.json
index f99184b50e..493c5fc319 100644
--- a/packages/type-storage/package.json
+++ b/packages/type-storage/package.json
@@ -30,9 +30,9 @@
   "homepage": "https://github.com/polkadot-js/api/tree/master/packages/type-storage#readme",
   "dependencies": {
     "@babel/runtime": "^7.4.0",
-    "@polkadot/keyring": "^0.41.1",
+    "@polkadot/keyring": "^0.42.0-beta.0",
     "@polkadot/types": "^0.51.1",
-    "@polkadot/util": "^0.41.1",
-    "@polkadot/util-crypto": "^0.41.1"
+    "@polkadot/util": "^0.42.0-beta.0",
+    "@polkadot/util-crypto": "^0.42.0-beta.0"
   }
 }
diff --git a/packages/types/package.json b/packages/types/package.json
index ffdf64a495..45656deab8 100644
--- a/packages/types/package.json
+++ b/packages/types/package.json
@@ -30,7 +30,7 @@
   "homepage": "https://github.com/polkadot-js/api/tree/master/packages/types#readme",
   "dependencies": {
     "@babel/runtime": "^7.4.0",
-    "@polkadot/keyring": "^0.41.1",
-    "@polkadot/util": "^0.41.1"
+    "@polkadot/keyring": "^0.42.0-beta.0",
+    "@polkadot/util": "^0.42.0-beta.0"
   }
 }
diff --git a/packages/types/src/index.ts b/packages/types/src/index.ts
index 655206e986..b88317cd24 100644
--- a/packages/types/src/index.ts
+++ b/packages/types/src/index.ts
@@ -5,5 +5,9 @@
 // NOTE When adding any types here, we need to update the coumentation links as
 // well - <root>/docs/SUMMARY.md as well as ../README.md
 
+import { assertSingletonPackage } from '@polkadot/util';
+
+assertSingletonPackage('@polkadot/types');
+
 export * from './codec';
 export * from './index.types';
diff --git a/yarn.lock b/yarn.lock
index 4522a48295..54ee732087 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1579,14 +1579,14 @@
     typescript "^3.3.4000"
     vuepress "^1.0.0-alpha.44"
 
-"@polkadot/keyring@^0.41.1":
-  version "0.41.1"
-  resolved "https://registry.yarnpkg.com/@polkadot/keyring/-/keyring-0.41.1.tgz#d6c6a179e3546385eccd5b61011d46c3d52eb8cf"
-  integrity sha512-kN3Op1TffWJfcnag+eTiFafx2z9jubjk9abU8fqlFM1qR0TzCOyLboB6JP0bUdSy3nu9+36qGi48HTAd3SOtCQ==
+"@polkadot/keyring@^0.42.0-beta.0":
+  version "0.42.0-beta.0"
+  resolved "https://registry.yarnpkg.com/@polkadot/keyring/-/keyring-0.42.0-beta.0.tgz#f43af8a7b0dffc339f0f38517897663f08550660"
+  integrity sha512-wIL42FRknPMdVZhmEvuAm/A1nmIjyF7ZbJnaTFcpMUByww9CnLtsAJRJutclb8YQ+8yr8QDMeLNPxxcAkkY5pQ==
   dependencies:
     "@babel/runtime" "^7.4.0"
-    "@polkadot/util" "^0.41.1"
-    "@polkadot/util-crypto" "^0.41.1"
+    "@polkadot/util" "^0.42.0-beta.0"
+    "@polkadot/util-crypto" "^0.42.0-beta.0"
     "@types/bs58" "^4.0.0"
     bs58 "^4.0.1"
 
@@ -1595,13 +1595,13 @@
   resolved "https://registry.yarnpkg.com/@polkadot/ts/-/ts-0.1.56.tgz#ffd6e9c95704a7fb90b918193b9dc5c440114b27"
   integrity sha512-wnt4zXxZXyz6WaubTO/I+nUElwV2DogFzdl6CrKfVn2PTWp8uHN06W9s40FH57ORtmQfDr9rLRP8Nq+oIyElbg==
 
-"@polkadot/util-crypto@^0.41.1":
-  version "0.41.1"
-  resolved "https://registry.yarnpkg.com/@polkadot/util-crypto/-/util-crypto-0.41.1.tgz#6be426b8df0a48f52ac5f6de4eeff4b95c6962f6"
-  integrity sha512-cNTQxjn3O38uJx79hvBDYu88vkg/8Det88+sO+c9NqQ1PSVBf26kHwDtMZQnUTkGGV8Hn6sLKCYCgkvgXDE+Ww==
+"@polkadot/util-crypto@^0.42.0-beta.0":
+  version "0.42.0-beta.0"
+  resolved "https://registry.yarnpkg.com/@polkadot/util-crypto/-/util-crypto-0.42.0-beta.0.tgz#28474139cb2f974d6b0d645f17aa0a93bd4ac707"
+  integrity sha512-9XQVrZcmFkc60tggec/WqArgg04w+xPmEK9icPU4TGLdevnfAP10bTRo7k4o2cEkE/yMRUxdNYuT4U9x29K+PQ==
   dependencies:
     "@babel/runtime" "^7.4.0"
-    "@polkadot/util" "^0.41.1"
+    "@polkadot/util" "^0.42.0-beta.0"
     "@polkadot/wasm-crypto" "^0.5.1"
     "@polkadot/wasm-dalek-ed25519" "^0.5.1"
     "@polkadot/wasm-schnorrkel" "^0.5.1"
@@ -1617,10 +1617,10 @@
     tweetnacl "^1.0.1"
     xxhashjs "^0.2.2"
 
-"@polkadot/util@^0.41.1":
-  version "0.41.1"
-  resolved "https://registry.yarnpkg.com/@polkadot/util/-/util-0.41.1.tgz#b67762a0a7408138d843adc7240944e704e819e7"
-  integrity sha512-1mFHxxdXyRgeFk0ygfJklzsf6HiEEMikrpUgr+3Dw5S7KromjPD8EbWkpcZQZ3Png5PTwGyjrx7MYY4Ajiu5xQ==
+"@polkadot/util@^0.42.0-beta.0":
+  version "0.42.0-beta.0"
+  resolved "https://registry.yarnpkg.com/@polkadot/util/-/util-0.42.0-beta.0.tgz#0b6d38c675c463ab2b438bbefaa85e6ba0d34f53"
+  integrity sha512-1pNTyastJwJX7slWj0pLHs/h7rXujgrkJMu7qQoHkaKKGTsU27gbmF9/Kyg8aP9QrVlTUKBlo1ROPTMEcNN+dQ==
   dependencies:
     "@babel/runtime" "^7.4.0"
     "@types/bn.js" "^4.11.4"