diff --git a/extras/build-tests/nix/configs/default b/extras/build-tests/nix/configs/default
index c63d964b6..1dac98216 100644
--- a/extras/build-tests/nix/configs/default
+++ b/extras/build-tests/nix/configs/default
@@ -24,5 +24,5 @@ DISABLEUSERMOD=""
 OPEROVERRIDEVERIFY=""
 DISABLEEXTBANSTACKING=""
 GENCERTIFICATE="0"
-EXTRAPARA="--enable-werror"
+EXTRAPARA="--enable-werror --enable-asan"
 ADVANCED=""
diff --git a/unrealircd.in b/unrealircd.in
index 50b9c5517..91a4faf96 100644
--- a/unrealircd.in
+++ b/unrealircd.in
@@ -14,6 +14,11 @@ if [ "$1" = "start" ] ; then
 	if [ -r $PID_FILE ] ; then
 		mv -f $PID_FILE $PID_BACKUP
 	fi
+	# We use AddressSanitizer in development builds, but ASan does not dump core
+	# by default because older gcc/clang might dump a 16TB core file.
+	# We explicitly enable it here. Note that this only applies to 5.0.0-alpha
+	# and 5.0.0-beta releases and explicit --with-asan development builds:
+	export ASAN_OPTIONS=abort_on_error=1:disable_coredump=0:unmap_shadow_on_exit=1
 	# Check if ~/Unrealxxx/unrealircd.conf exists but the file
 	# ~/unrealircd/conf/unrealircd.conf does not.
 	# If so, then assume a user-build and give the user a nice hint...