diff --git a/.clang-format b/.clang-format
new file mode 100644
index 000000000..f0817e988
--- /dev/null
+++ b/.clang-format
@@ -0,0 +1,80 @@
+
+######################
+# clang-format options
+######################
+
+# ####
+# NOTE: The IOCCC style is somewhat similar to the Linux Kernel style
+#
+# See: https://clang.llvm.org/docs/ClangFormatStyleOptions.html
+#
+# NOTE: Linux Kernel style differences will be noted in comments below, with
+#       the Kernel style setting noted in a "Kernel style uses:" comment.
+# ####
+
+# A style complying with the LLVM coding standards
+#
+# See: https://llvm.org/docs/CodingStandards.html#include-style
+#
+BasedOnStyle: LLVM
+
+# Never put short ifs on the same line
+#
+AllowShortIfStatementsOnASingleLine: false
+
+# Use the same indentation level as for the switch statement
+#
+IndentCaseLabels: false
+
+# Always attach braces to surrounding context
+#
+BreakBeforeBraces: Linux
+
+# The number of columns to use for indentation
+#
+# Kernel style uses: IndentWidth: 8
+#
+IndentWidth: 4
+
+# Never use tab to indent
+#
+# Kernel style uses: UseTab: Always
+#
+UseTab: Never
+
+# Align escaped newlines as far left as possible, using the last line of the
+# preprocessor directive as the reference if it’s the longest.
+#
+# Kernel style uses: AlignEscapedNewlines: Right
+#
+AlignEscapedNewlines: LeftWithLastLine
+
+# The column limit
+#
+# Kernel style uses: ColumnLimit: 80
+#
+ColumnLimit: 131
+
+# The number of columns to use for indentation of preprocessor statements
+#
+# NOTE: When set to -1 (default) IndentWidth is used also for preprocessor statements.
+#
+# Kernel style uses: PPIndentWidth: -1
+#
+PPIndentWidth: 2
+
+# Indents directives after the hash
+#
+# Kernel style uses: IndentPPDirectives: None
+#
+IndentPPDirectives: AfterHash
+
+# Insert braces after control statements (if, else, for, do, and while) in
+#
+# Kernel style uses: InsertBraces: false
+#
+# WARNING: Setting this option to true could lead to incorrect code formatting due to clang-format’s
+#          lack of complete semantic information. As such, extra care should be taken to review code
+#          changes made by this option!
+#
+InsertBraces: true
diff --git a/1337.mk b/1337.mk
index 483154ec3..a9293d0b2 100644
--- a/1337.mk
+++ b/1337.mk
@@ -3,44 +3,27 @@
 # extended utility rules
 ########################
 
-.PHONY: indent_clean indent_clobber install
-
-# you may be able to misunderstand the source by reading indent.c
-#
-indent.c: ${PROG}.c
-	@if which "${GINDENT}" >/dev/null 2>&1; then \
-	    echo ${RM} -f $@; \
-	    ${RM} -f $@; \
-	    echo "${GINDENT} < $< > $@"; \
-	    ${GINDENT} < $< > $@; \
-	elif which "${INDENT}" >/dev/null 2>&1; then \
-	    echo ${RM} -f $@; \
-	    ${RM} -f $@; \
-	    echo "${INDENT} < $< > $@"; \
-	    ${INDENT} < $< > $@; \
-	else \
-	    echo "no indent tool found, ident $< yourself, sorry"; \
-	    echo "exit 17"; \
-	    exit 17; \
-	fi
-
-indent_clean: clean
-	@-if [ -f indent.c ]; then \
-	    echo ${RM} -f indent.c; \
-	    ${RM} -f indent.c; \
-	fi
-
-indent_clobber: indent_clean clobber
-	@-if [ -e sandwich ]; then \
-	    ${RM} -f sandwich; \
-	    echo 'ate sandwich'; \
-	fi
-
 install:
 	@echo "Dr. Spock says that is not logical!"
 	@${TRUE}
 
 
+######################
+# clang-format options
+######################
+
+.PHONY: clang-format
+
+# NOTE: The IOCCC Judges set CLANG_FORMAT_STYLE according to the ".clang-format" file.
+#
+#	https://github.com/ioccc-src/winner/blob/master/.clang-format
+#
+# NOTE: Please don't add "// clang-format off" to your code: that is both annoying, and is easily disabled.
+#
+clang-format: ${PROG}.c
+	${CLANG_FORMAT} -style=file ${PROG}.c
+
+
 #####################
 # make a difference #
 #####################
diff --git a/var.mk b/var.mk
index a641a8763..7b2eec456 100644
--- a/var.mk
+++ b/var.mk
@@ -39,6 +39,7 @@ CHGRP= chgrp
 CHMOD= chmod
 CKSUM= cksum
 CLANG= clang
+CLANG_FORMAT= clang-format
 CLANG_PLUSPLUS= clang++
 CLEAR= clear
 CMP= cmp