diff --git a/.travis.yml b/.travis.yml
index 58a4ab2..fc67cae 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -257,8 +257,8 @@ install:
       cabal --version
       travis_retry cabal update -v
       echo 'packages: .' > cabal.project
-      echo 'package brittany'        > cabal.project.local
-      echo '  ghc-options: -Werror' >> cabal.project.local
+      echo 'package brittany'                          > cabal.project.local
+      echo '  ghc-options: -Werror -with-rtsopts=-N1' >> cabal.project.local
       rm -f cabal.project.freeze
       cabal new-build -j$JOBS --enable-test --enable-benchmarks --dep
       cabal new-build -j$JOBS --disable-tests --disable-benchmarks --dep
@@ -271,13 +271,13 @@ script:
   set -ex
   case "$BUILD" in
     stack)
-      better_wait stack -j$JOBS --no-terminal $ARGS test --bench --no-run-benchmarks --haddock --no-haddock-deps --ghc-options="-j1 +RTS -M500M -RTS -Werror -with-rtsopts -N1"
+      better_wait stack -j$JOBS --no-terminal $ARGS test --bench --no-run-benchmarks --haddock --no-haddock-deps --ghc-options="-j1 +RTS -M500M -RTS -Werror -with-rtsopts=-N1"
       ;;
     cabal)
       if [ -f configure.ac ]; then autoreconf -i; fi
       cabal configure --enable-tests --enable-benchmarks -v  # -v2 provides useful information for debugging
       better_wait cabal build -j$JOBS --ghc-options="-j1 +RTS -M500M -RTS -Werror" # this builds all libraries and executables (including tests/benchmarks)
-      time cabal test --ghc-options="-with-rtsopts -N1"
+      time cabal test --ghc-options="-with-rtsopts=-N1"
       ;;
     cabaldist)
       # cabal check
@@ -292,7 +292,7 @@ script:
     canew)
       better_wait cabal new-build -j$JOBS --ghc-options="-j1 +RTS -M500M -RTS" --disable-tests --disable-benchmarks
       better_wait cabal new-build -j$JOBS --ghc-options="-j1 +RTS -M500M -RTS" --enable-tests --enable-benchmarks
-      time cabal new-test -j1 --ghc-options="-j1 +RTS -M500M -RTS -with-rtsopts -N1"
+      time cabal new-test -j1 --ghc-options="-j1 +RTS -M500M -RTS"
       ;;
   esac
   set +ex