diff --git a/.dir-locals.el b/.dir-locals.el
index 3fe2340c9614..887f06379adf 100644
--- a/.dir-locals.el
+++ b/.dir-locals.el
@@ -11,5 +11,7 @@
  (java-mode
   (indent-tabs-mode . nil)
   (c-basic-offset . 4))
+ (ruby-mode
+  (ruby-indent-level . 4))
  (change-log-mode
   (indent-tabs-mode . nil)))
diff --git a/.editorconfig b/.editorconfig
index 618d3f1c43b9..77f5dceebde1 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -1,6 +1,6 @@
 # Editor configuration, see http://editorconfig.org
 
-[*.{c,cpp,h}]
+[*.{c,cpp,h,rb}]
 indent_style = space
 indent_size = 4
 tab_width = 4
diff --git a/ChangeLog b/ChangeLog
index c79215acdf27..224fadc7620b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2021-01-27  Angelos Oikonomopoulos  <angelos@igalia.com>
+
+        Set ruby-indent-level to 4
+        https://bugs.webkit.org/show_bug.cgi?id=220982
+
+        Reviewed by Fujii Hironori.
+
+        All the ruby source files seem to default to 4 as the indent
+        level; make it official.
+
+        * .dir-locals.el:
+        * .editorconfig:
+
 2021-01-23  Xan Lopez  <xan@igalia.com>
 
         [JSC] Allow to build WebAssembly without B3