diff --git a/package.json b/package.json
index ac08372843..cb8f303ffa 100644
--- a/package.json
+++ b/package.json
@@ -81,7 +81,7 @@
     "linkifyjs": "^2.1.6",
     "lodash": "^4.13.1",
     "lolex": "2.3.2",
-    "matrix-js-sdk": "1.1.0",
+    "matrix-js-sdk": "1.2.0-rc.1",
     "optimist": "^0.6.1",
     "pako": "^1.0.5",
     "png-chunks-extract": "^1.0.0",
diff --git a/yarn.lock b/yarn.lock
index 115aa73f45..6e3f112da3 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1450,13 +1450,6 @@ balanced-match@^1.0.0:
   resolved "https://registry.yarnpkg.com/balanced-match/-/balanced-match-1.0.0.tgz#89b4d199ab2bee49de164ea02b89ce462d71b767"
   integrity sha1-ibTRmasr7kneFk6gK4nORi1xt2c=
 
-base-x@3.0.4:
-  version "3.0.4"
-  resolved "https://registry.yarnpkg.com/base-x/-/base-x-3.0.4.tgz#94c1788736da065edb1d68808869e357c977fa77"
-  integrity sha512-UYOadoSIkEI/VrRGSG6qp93rp2WdokiAiNYDfGW5qURAY8GiAQkvMbwNNSDYiVJopqv4gCna7xqf4rrNGp+5AA==
-  dependencies:
-    safe-buffer "^5.0.1"
-
 base-x@^3.0.2:
   version "3.0.5"
   resolved "https://registry.yarnpkg.com/base-x/-/base-x-3.0.5.tgz#d3ada59afed05b921ab581ec3112e6444ba0795a"
@@ -4884,14 +4877,13 @@ mathml-tag-names@^2.0.1:
   resolved "https://registry.yarnpkg.com/mathml-tag-names/-/mathml-tag-names-2.1.0.tgz#490b70e062ee24636536e3d9481e333733d00f2c"
   integrity sha512-3Zs9P/0zzwTob2pdgT0CHZuMbnSUSp8MB1bddfm+HDmnFWHGT4jvEZRf+2RuPoa+cjdn/z25SEt5gFTqdhvJAg==
 
-matrix-js-sdk@1.1.0:
-  version "1.1.0"
-  resolved "https://registry.yarnpkg.com/matrix-js-sdk/-/matrix-js-sdk-1.1.0.tgz#f0db49de2aa0b0d50c1fe49da538beb4926ce59c"
-  integrity sha512-ECoMN6DkwPdKiMa/jSoMkSDngFCo6x7oH84rLd1NtD7lBPl3Ejj6ARa0iIELE7u0OUO6J0FzdWh7Hd0ZnVTmww==
+matrix-js-sdk@1.2.0-rc.1:
+  version "1.2.0-rc.1"
+  resolved "https://registry.yarnpkg.com/matrix-js-sdk/-/matrix-js-sdk-1.2.0-rc.1.tgz#3bb495fc5dce9372e420455cd6378ddd85844026"
+  integrity sha512-2/lcL4QP077Du22G1W+k5KAgSreFxKbZW2dmtI5wr9icPACHHxxN/pEvWLiKkW7Q3+uulb05uTilM6zip9ux/g==
   dependencies:
     another-json "^0.2.0"
     babel-runtime "^6.26.0"
-    base-x "3.0.4"
     bluebird "^3.5.0"
     browser-request "^0.3.3"
     bs58 "^4.0.1"