diff --git a/.travis.yml b/.travis.yml
index c182012..97103b2 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -13,11 +13,11 @@ env:
     - RACKET_VERSION=6.1.1   COV=false
     - RACKET_VERSION=6.2     COV=false
     - RACKET_VERSION=6.3     COV=false
-    - RACKET_VERSION=6.4     COV=true
-    - RACKET_VERSION=6.5     COV=true
-    - RACKET_VERSION=6.6     COV=true
-    - RACKET_VERSION=6.7     COV=true
-    - RACKET_VERSION=6.8     COV=true
+    - RACKET_VERSION=6.4     COV=false
+    - RACKET_VERSION=6.5     COV=false
+    - RACKET_VERSION=6.6     COV=false
+    - RACKET_VERSION=6.7     COV=false
+    - RACKET_VERSION=6.8     COV=false
     - RACKET_VERSION=6.9     COV=true
     - RACKET_VERSION=6.10    COV=true
     - RACKET_VERSION=6.10.1  COV=true
@@ -41,4 +41,4 @@ script:
 - if $COV; then raco doc-coverage "$(basename "$TRAVIS_BUILD_DIR")"; fi
 - if $COV; then raco cover -s main -s test -s doc -f codecov -f html -d ~/coverage . || true; fi
 # TODO: add an option to cover to run the "outer" module too, not just the submodules.
-# TODO: deploy the coverage info.
\ No newline at end of file
+# TODO: deploy the coverage info.