diff --git a/src/cssplit.awk b/src/cssplit.awk
new file mode 100755
index 0000000..0ddbdb0
--- /dev/null
+++ b/src/cssplit.awk
@@ -0,0 +1,68 @@
+#!/usr/bin/env awk -f
+#
+# (C) Copyright 2024 Diomidis Spinellis
+#
+# This file is part of CScout.
+#
+# CScout is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# CScout is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with CScout.  If not, see <http://www.gnu.org/licenses/>.
+#
+# Split CScout processing input into files containing the specified number
+# of compilation units (CUs).
+#
+
+function begin_project() {
+	outfile = sprintf("file-%04d.cs", ++file_number)
+	print "#pragma project \"cssplit\"" >outfile
+	print "#pragma block_enter" >outfile
+}
+
+function end_project() {
+	print "#pragma block_exit" >outfile
+	close(outfile)
+}
+
+BEGIN {
+	if (ARGC < 2) {
+		print "Usage: cssplit N" > "/dev/stderr"
+		exit 1
+	}
+
+	N = ARGV[1]
+	ARGV[1] = ""
+}
+
+# CU processing path name starts with a /
+/#pragma echo "Processing \// {
+	if (cu_count % N == 0) {
+		if (cu_count > 0)
+			end_project();
+		begin_project();
+	}
+	in_cu = 1;
+	cu_count++
+}
+
+in_cu {
+	print $0 >outfile
+}
+
+# CU processing path name starts with a /
+/#pragma echo "Done processing \// {
+	in_cu = 0
+}
+
+END {
+	if (cu_count > 0)
+		end_project();
+}