diff --git a/.gitignore b/.gitignore
index 5c978cc5cd..b31a61b02a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,6 +7,10 @@ target/
 /linker-interface/**/scalajs-logging-src-jars/
 /node_modules/
 
+# scalafmt generated
+scripts/.coursier
+scripts/.scalafmt*
+
 # IDE specific
 .cache
 .classpath
diff --git a/.scalafmt.conf b/.scalafmt.conf
new file mode 100644
index 0000000000..638296ff63
--- /dev/null
+++ b/.scalafmt.conf
@@ -0,0 +1,52 @@
+# Overall we are trying to use default settings to the
+# maximum extent possible. Removing non-default
+# settings is preferred over adding especially as
+# the Scala language evolves and styles change.
+# Test upgrades: $ scripts/scalafmt --test 2> diff.txt
+version = 3.8.0
+docstrings.style = AsteriskSpace
+project.git = true
+project.excludePaths = [
+  "glob:**/scalalib/**",
+  "glob:**/project/**",
+  "glob:**/test-suite/js/src/test/resources/SourceMapTestTemplate.scala"
+]
+
+# Default runner.dialect is deprecated, so set explicitly
+runner.dialect = scala213source3
+
+# new additions
+fileOverride {
+  "glob:**/scala3/**" {
+    runner.dialect = scala3
+  }
+}
+
+optIn.breakChainOnFirstMethodDot = false
+
+# Preserve some overflow
+newlines.avoidForSimpleOverflow = [tooLong, punct, slc]
+
+indent.callSite = 4
+indentOperator.exemptScope = aloneArgOrBody
+indentOperator.include = ".*"
+indentOperator.exclude = "^(?:&&|\\|\\||\\+)$"
+
+newlines.source = keep
+
+binPack.preset = true
+binPack.parentConstructors = keep
+binPack.unsafeCallSite = oneline
+binPack.literalsExclude = []
+binPack.literalsIncludeSimpleExpr = true
+
+# Keep control sites more streamlined
+indent.ctrlSite = 4
+danglingParentheses.ctrlSite = false
+
+rewriteTokens = {
+  "⇒": "=>"
+  "→": "->"
+  "←": "<-"
+}
+
diff --git a/scripts/scalafmt b/scripts/scalafmt
new file mode 100755
index 0000000000..fdebe25dab
--- /dev/null
+++ b/scripts/scalafmt
@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+
+set -e
+
+HERE="`dirname $0`"
+VERSION=$(sed -nre "s#\s*version[^0-9]+([0-9.]+)#\1#p" $HERE/../.scalafmt.conf)
+COURSIER="$HERE/.coursier"
+SCALAFMT="$HERE/.scalafmt-$VERSION"
+
+if [ ! -f $COURSIER ]; then
+  curl -L -o $COURSIER https://git.io/coursier-cli
+  chmod +x $COURSIER
+fi
+
+if [ ! -f $SCALAFMT ]; then
+  $COURSIER bootstrap org.scalameta:scalafmt-cli_2.13:$VERSION -r sonatype:snapshots --main org.scalafmt.cli.Cli -o $SCALAFMT
+  chmod +x $SCALAFMT
+fi
+
+$SCALAFMT "$@"