diff --git a/.travis.yml b/.travis.yml
index 1700e1d..b335a34 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -17,11 +17,13 @@ env:
  #- CABALVER=1.16 GHCVER=7.4.2
  #- CABALVER=1.16 GHCVER=7.6.1
  #- CABALVER=1.16 GHCVER=7.6.2
- - CABALVER=1.18 GHCVER=7.6.3
+ #- CABALVER=1.18 GHCVER=7.6.3
+ - CABALVER=1.20 GHCVER=7.6.3
  #- CABALVER=1.18 GHCVER=7.8.1  # see note about Alex/Happy for GHC >= 7.8
  #- CABALVER=1.18 GHCVER=7.8.2
  #- CABALVER=1.18 GHCVER=7.8.3
- - CABALVER=1.18 GHCVER=7.8.4
+ #- CABALVER=1.18 GHCVER=7.8.4
+ - CABALVER=1.20 GHCVER=7.8.4
  #- CABALVER=1.22 GHCVER=7.10.1
  - CABALVER=1.22 GHCVER=7.10.2
  - CABALVER=head GHCVER=head   # see section about GHC HEAD snapshots