diff --git a/pkgs/development/tools/build-managers/bazel/0.4.nix b/pkgs/development/tools/build-managers/bazel/0.4.nix
index 7fa39ef21627..69f467f577c8 100644
--- a/pkgs/development/tools/build-managers/bazel/0.4.nix
+++ b/pkgs/development/tools/build-managers/bazel/0.4.nix
@@ -65,8 +65,9 @@ stdenv.mkDerivation rec {
   ];
 
   buildPhase = ''
+    export TMPDIR=/tmp/.bazel-$UID
     ./compile.sh
-    ./output/bazel --output_user_root=/tmp/.bazel build //scripts:bash_completion \
+    ./output/bazel --output_user_root=$TMPDIR/.bazel build //scripts:bash_completion \
       --spawn_strategy=standalone \
       --genrule_strategy=standalone
     cp bazel-bin/scripts/bazel-complete.bash output/
diff --git a/pkgs/development/tools/build-managers/bazel/default.nix b/pkgs/development/tools/build-managers/bazel/default.nix
index 28214e94c7aa..0441ba0c665d 100644
--- a/pkgs/development/tools/build-managers/bazel/default.nix
+++ b/pkgs/development/tools/build-managers/bazel/default.nix
@@ -96,9 +96,9 @@ stdenv.mkDerivation rec {
   # Change this to $(mktemp -d) as soon as we figure out why.
 
   buildPhase = ''
-    export TMPDIR=/tmp
+    export TMPDIR=/tmp/.bazel-$UID
     ./compile.sh
-    ./output/bazel --output_user_root=/tmp/.bazel build //scripts:bash_completion \
+    ./output/bazel --output_user_root=$TMPDIR/.bazel build //scripts:bash_completion \
       --spawn_strategy=standalone \
       --genrule_strategy=standalone
     cp bazel-bin/scripts/bazel-complete.bash output/