diff --git a/lsg.c b/lsg.c
index 54b7816..bbad187 100644
--- a/lsg.c
+++ b/lsg.c
@@ -626,12 +626,19 @@ static void gen_man(struct lls_parse_result *lpr, const char *cmdline)
 	if (suite.commands[0].name.orig) {
 		char date[200];
 		const char *version_string;
-
 		if (!suite.date) {
-			t = time(NULL);
-			tmp = localtime(&t);
+			/* Assume that the SOURCE_DATE_EPOCH environment
+			 * variable will contan a correct, positive integer in
+			 * the time_t range. See:
+			 * <https://reproducible-builds.org/specs/source-date-epoch/>
+			 * for more information */
+			char *source_date_epoch;
+			if ((source_date_epoch = getenv("SOURCE_DATE_EPOCH")) == NULL ||
+				(t = (time_t)strtoll(source_date_epoch, NULL, 10)) <= 0)
+					time(&t);
+			tmp = gmtime(&t);
 			if (tmp == NULL) {
-				perror("localtime");
+				perror("gmtime");
 				exit(EXIT_FAILURE);
 			}
 			if (strftime(date, sizeof(date), "%B %Y", tmp) == 0) {