diff --git a/.travis.yml b/.travis.yml
index 8f546b9e..7d9f21cb 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,6 +6,7 @@ matrix:
     env: EXECUTE_DEPLOYMENT=true
   - php: 7.3
     env: deps=low UPDATE_TOOLS=true
+  - php: 7.4
   fast_finish: true
 cache:
   directories:
diff --git a/Makefile b/Makefile
index 98ffa661..ebb2688b 100644
--- a/Makefile
+++ b/Makefile
@@ -149,4 +149,4 @@ tools/infection.pubkey:
 	curl -Ls https://github.com/infection/infection/releases/download/0.13.2/infection.phar.pubkey -o tools/infection.pubkey
 
 tools/box:
-	curl -Ls https://github.com/humbug/box/releases/download/3.8.3/box.phar -o tools/box && chmod +x tools/box
+	curl -Ls https://github.com/humbug/box/releases/download/3.8.4/box.phar -o tools/box && chmod +x tools/box