diff --git a/.ci/meta_builds.sh b/.ci/meta_builds.sh
index eaf90294..87f04028 100755
--- a/.ci/meta_builds.sh
+++ b/.ci/meta_builds.sh
@@ -95,3 +95,7 @@ bash .ci/testbuild.sh "NOTEST" "-DLTC_NO_TEST" "$3" "$4" "$5"
 make clean &>/dev/null
 
 bash .ci/testbuild.sh "NOFILE" "-DLTC_NO_FILE" "$3" "$4" "$5"
+
+# ref:         $Format:%D$
+# git commit:  $Format:%H$
+# commit time: $Format:%ai$
diff --git a/.ci/printinfo.sh b/.ci/printinfo.sh
index 213af5b1..21e1fec7 100644
--- a/.ci/printinfo.sh
+++ b/.ci/printinfo.sh
@@ -18,3 +18,7 @@ then
 fi
 echo "${CC}="`${CC} -dumpversion`
 echo
+
+# ref:         $Format:%D$
+# git commit:  $Format:%H$
+# commit time: $Format:%ai$
diff --git a/.ci/testbuild.sh b/.ci/testbuild.sh
index ae066222..96810f9d 100755
--- a/.ci/testbuild.sh
+++ b/.ci/testbuild.sh
@@ -20,3 +20,7 @@ if find testok.txt -type f 1>/dev/null 2>/dev/null ; then
    exit 0
 fi
 exit 1
+
+# ref:         $Format:%D$
+# git commit:  $Format:%H$
+# commit time: $Format:%ai$
diff --git a/.ci/valgrind.sh b/.ci/valgrind.sh
index 0aa3425f..87ad8842 100755
--- a/.ci/valgrind.sh
+++ b/.ci/valgrind.sh
@@ -31,3 +31,7 @@ alive_pid=$!
 valgrind --error-exitcode=666 --leak-check=full --show-leak-kinds=all --errors-for-leak-kinds=all ./test >test_std.txt 2> >(tee -a test_err.txt >&2) || { kill $alive_pid; echo "Valgrind failed"; exit 1; }
 
 kill $alive_pid
+
+# ref:         $Format:%D$
+# git commit:  $Format:%H$
+# commit time: $Format:%ai$
diff --git a/coverity.sh b/coverity.sh
index 8f305962..5f40097c 100755
--- a/coverity.sh
+++ b/coverity.sh
@@ -38,3 +38,7 @@ curl -k --form project=libtomcrypt \
   --form version=\"${myversion}\" \
   --form description="\"libtomcrypt version ${myversion}\"" \
   https://scan.coverity.com/builds?project=libtom%2Flibtomcrypt
+
+# ref:         $Format:%D$
+# git commit:  $Format:%H$
+# commit time: $Format:%ai$
diff --git a/helper.pl b/helper.pl
index 591ce185..a1eebeeb 100755
--- a/helper.pl
+++ b/helper.pl
@@ -382,3 +382,7 @@ $failure ||= process_makefiles(1) if $update_makefiles;
 
 die_usage unless defined $failure;
 exit $failure ? 1 : 0;
+
+# ref:         $Format:%D$
+# git commit:  $Format:%H$
+# commit time: $Format:%ai$
diff --git a/makefile.mingw b/makefile.mingw
index 0b0f16f0..a09350ac 100644
--- a/makefile.mingw
+++ b/makefile.mingw
@@ -292,3 +292,7 @@ install_bins: hashsum
 install_docs: doc/crypt.pdf
 	cmd /c if not exist "$(PREFIX)\doc" mkdir "$(PREFIX)\doc"
 	copy /Y doc\crypt.pdf "$(PREFIX)\doc"
+
+# ref:         $Format:%D$
+# git commit:  $Format:%H$
+# commit time: $Format:%ai$
diff --git a/makefile.msvc b/makefile.msvc
index 7b9a2782..8ae89f0e 100644
--- a/makefile.msvc
+++ b/makefile.msvc
@@ -277,3 +277,7 @@ install_bins: hashsum
 install_docs: doc/crypt.pdf
 	cmd /c if not exist "$(PREFIX)\doc" mkdir "$(PREFIX)\doc"
 	copy /Y doc\crypt.pdf "$(PREFIX)\doc"
+
+# ref:         $Format:%D$
+# git commit:  $Format:%H$
+# commit time: $Format:%ai$
diff --git a/makefile.unix b/makefile.unix
index 96a1fd93..baa39641 100644
--- a/makefile.unix
+++ b/makefile.unix
@@ -298,3 +298,7 @@ install_bins: hashsum
 install_docs: doc/crypt.pdf
 	@mkdir -p $(DESTDIR)$(DATAPATH)
 	@cp doc/crypt.pdf $(DESTDIR)$(DATAPATH)/
+
+# ref:         $Format:%D$
+# git commit:  $Format:%H$
+# commit time: $Format:%ai$
diff --git a/makefile_include.mk b/makefile_include.mk
index 1df31a2e..54f9cc4b 100644
--- a/makefile_include.mk
+++ b/makefile_include.mk
@@ -475,3 +475,7 @@ codecheck: $(call print-help,codecheck,Check the code of the library)
 	perlcritic *.pl
 
 help: $(call print-help,help,That's what you're currently looking at)
+
+# ref:         $Format:%D$
+# git commit:  $Format:%H$
+# commit time: $Format:%ai$
diff --git a/updatemakes.sh b/updatemakes.sh
index 14210c05..5acb9530 100755
--- a/updatemakes.sh
+++ b/updatemakes.sh
@@ -10,3 +10,7 @@ if [ $# -eq 1 ] && [ "$1" == "-c" ]; then
 fi
 
 exit 0
+
+# ref:         $Format:%D$
+# git commit:  $Format:%H$
+# commit time: $Format:%ai$