diff --git a/.builds/alpine.yml b/.builds/alpine.yml
index 36227c48..c636ece6 100644
--- a/.builds/alpine.yml
+++ b/.builds/alpine.yml
@@ -19,7 +19,7 @@ sources:
 tasks:
   - setup: |
       cd wlroots
-      meson build --default-library=both -Dauto_features=enabled -Dxcb-errors=disabled
+      meson build --fatal-meson-warnings --default-library=both -Dauto_features=enabled -Dxcb-errors=disabled
   - build: |
       cd wlroots
       ninja -C build
diff --git a/.builds/archlinux.yml b/.builds/archlinux.yml
index 6986ea6a..bcab5f06 100644
--- a/.builds/archlinux.yml
+++ b/.builds/archlinux.yml
@@ -20,8 +20,8 @@ sources:
 tasks:
   - setup: |
       cd wlroots
-      CC=gcc meson build-gcc --default-library=both -Dauto_features=enabled --prefix /usr
-      CC=clang meson build-clang -Dauto_features=enabled
+      CC=gcc meson build-gcc --fatal-meson-warnings --default-library=both -Dauto_features=enabled --prefix /usr
+      CC=clang meson build-clang --fatal-meson-warnings -Dauto_features=enabled
   - gcc: |
       cd wlroots/build-gcc
       ninja
diff --git a/.builds/freebsd.yml b/.builds/freebsd.yml
index 4262feed..a570e204 100644
--- a/.builds/freebsd.yml
+++ b/.builds/freebsd.yml
@@ -27,7 +27,7 @@ sources:
 tasks:
   - wlroots: |
       cd wlroots
-      meson build -Dauto_features=enabled
+      meson build --fatal-meson-warnings -Dauto_features=enabled
       ninja -C build
       sudo ninja -C build install
   - tinywl: |