diff --git a/.travis.yml b/.travis.yml
index a5e1804..8cd842f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,7 +5,7 @@ install:
   - npm install terser
   - npm install uglifycss
   - npm install typescript@3.9.3
-  - npm install jest
+  - npm install jest @types/jest ts-jest
   - npm install @types/jquery
 script:
   - tsc -v