diff --git a/package.json b/package.json
index fb4facb4e..3f31a3aca 100644
--- a/package.json
+++ b/package.json
@@ -31,8 +31,8 @@
     "build:res": "node scripts/copy-res.js",
     "build:modernizr": "modernizr -c .modernizr.json -d src/vector/modernizr.js",
     "build:compile": "npm run reskindex && babel --source-maps -d lib src",
-    "build:bundle": "cross-env NODE_ENV=production webpack -p --progress",
-    "build:bundle:dev": "webpack --optimize-occurence-order --progress",
+    "build:bundle": "cross-env NODE_ENV=production webpack -p --progress --bail",
+    "build:bundle:dev": "webpack --optimize-occurence-order --progress --bail",
     "build:electron": "npm run clean && npm run build && npm run install:electron && build -wml --ia32 --x64",
     "build": "npm run reskindex && npm run build:res && npm run build:bundle",
     "build:dev": "npm run reskindex && npm run build:res && npm run build:bundle:dev",
diff --git a/scripts/fetch-develop.deps.sh b/scripts/fetch-develop.deps.sh
index 4fa1a4a22..e2d40341a 100755
--- a/scripts/fetch-develop.deps.sh
+++ b/scripts/fetch-develop.deps.sh
@@ -49,42 +49,47 @@ function dodep() {
         [ "$curbranch" != 'develop' ] && clone $org $repo develop
     } || return $?
 
-    (
-        cd $repo
-        echo "$repo set to branch "`git rev-parse --abbrev-ref HEAD`
-    )
+    echo "$repo set to branch "`git -C "$repo" rev-parse --abbrev-ref HEAD`
 
     mkdir -p node_modules
     rm -r "node_modules/$repo" 2>/dev/null || true
     ln -sv "../$repo" node_modules/
+
+    (
+        cd $repo
+        npm install
+    )
 }
 
+##############################
+
 echo -en 'travis_fold:start:matrix-js-sdk\r'
 echo 'Setting up matrix-js-sdk'
 
 dodep matrix-org matrix-js-sdk
-(
-    cd node_modules/matrix-js-sdk
-    npm install
-)
 
 echo -en 'travis_fold:end:matrix-js-sdk\r'
 
+##############################
+
 echo -en 'travis_fold:start:matrix-react-sdk\r'
 echo 'Setting up matrix-react-sdk'
 
 dodep matrix-org matrix-react-sdk
 
-mkdir -p node_modules/matrix-react-sdk/node_modules
+# replace the version of js-sdk that got pulled into react-sdk with a symlink
+# to our version. Make sure to do this *after* doing 'npm i' in react-sdk,
+# otherwise npm helpfully moves another-json from matrix-js-sdk/node_modules
+# into matrix-react-sdk/node_modules.
+#
+# (note this matches the instructions in the README.)
+rm -r node_modules/matrix-react-sdk/node_modules/matrix-js-sdk
 ln -s ../../matrix-js-sdk node_modules/matrix-react-sdk/node_modules/
 
-(
-    cd node_modules/matrix-react-sdk
-    npm install
-)
-
 echo -en 'travis_fold:end:matrix-react-sdk\r'
 
+##############################
+
 # Link the reskindex binary in place: if we used npm link,
 # npm would do this for us, but we don't because we'd have
 # to define the npm prefix somewhere so it could put the
diff --git a/scripts/jenkins.sh b/scripts/jenkins.sh
index 4f2e94056..7b5b4c8e2 100755
--- a/scripts/jenkins.sh
+++ b/scripts/jenkins.sh
@@ -8,8 +8,11 @@ nvm use 6
 
 set -x
 
-# check out corresponding branches of dependencies
-`dirname $0`/fetch-develop.deps.sh
+# check out corresponding branches of dependencies.
+#
+# clone the deps with depth 1: we know we will only ever need that one
+# commit.
+`dirname $0`/fetch-develop.deps.sh --depth 1
 
 npm install