diff --git a/tools/fuzzer/runners/client_fuzzer.sh b/tools/fuzzer/runners/client_fuzzer.sh
index 239d552c57d34a45d498cc9693e8b7c558dc93df..97d4e60d90831a6597a2bd38a5856dc51d8c2624 100644
--- a/tools/fuzzer/runners/client_fuzzer.sh
+++ b/tools/fuzzer/runners/client_fuzzer.sh
@@ -33,7 +33,7 @@ flags="-max_total_time=$runtime -artifact_prefix=fuzzer_output/ -max_len=2048"
 
 if [ "$jobs" != "1" ]
 then
-  flags="-jobs=$jobs -workers=$jobs"
+  flags="-jobs=$jobs -workers=$jobs $flags"
 fi
 
 if [ "$config" == "asan-trace-cmp" ]
diff --git a/tools/fuzzer/runners/hpack_parser_fuzzer_test.sh b/tools/fuzzer/runners/hpack_parser_fuzzer_test.sh
index e69b4b4dfe2973c46b91014d1623e6cd52e30620..c6f70a623dcee9d3e2fcf99a6c4f89af9df29fa2 100644
--- a/tools/fuzzer/runners/hpack_parser_fuzzer_test.sh
+++ b/tools/fuzzer/runners/hpack_parser_fuzzer_test.sh
@@ -33,7 +33,7 @@ flags="-max_total_time=$runtime -artifact_prefix=fuzzer_output/ -max_len=512"
 
 if [ "$jobs" != "1" ]
 then
-  flags="-jobs=$jobs -workers=$jobs"
+  flags="-jobs=$jobs -workers=$jobs $flags"
 fi
 
 if [ "$config" == "asan-trace-cmp" ]
diff --git a/tools/fuzzer/runners/http_fuzzer_test.sh b/tools/fuzzer/runners/http_fuzzer_test.sh
index c190ba40b604087230d1e36bf6a066af41aa6726..bb54a238145618e917e58158208c5d1086662e48 100644
--- a/tools/fuzzer/runners/http_fuzzer_test.sh
+++ b/tools/fuzzer/runners/http_fuzzer_test.sh
@@ -33,7 +33,7 @@ flags="-max_total_time=$runtime -artifact_prefix=fuzzer_output/ -max_len=2048"
 
 if [ "$jobs" != "1" ]
 then
-  flags="-jobs=$jobs -workers=$jobs"
+  flags="-jobs=$jobs -workers=$jobs $flags"
 fi
 
 if [ "$config" == "asan-trace-cmp" ]
diff --git a/tools/fuzzer/runners/json_fuzzer_test.sh b/tools/fuzzer/runners/json_fuzzer_test.sh
index 9fc6271976b6d747878ba7b5dc2b58e1a2c32991..e11e25dc097a51def12231be1b1488d78dcd1563 100644
--- a/tools/fuzzer/runners/json_fuzzer_test.sh
+++ b/tools/fuzzer/runners/json_fuzzer_test.sh
@@ -33,7 +33,7 @@ flags="-max_total_time=$runtime -artifact_prefix=fuzzer_output/ -max_len=512"
 
 if [ "$jobs" != "1" ]
 then
-  flags="-jobs=$jobs -workers=$jobs"
+  flags="-jobs=$jobs -workers=$jobs $flags"
 fi
 
 if [ "$config" == "asan-trace-cmp" ]
diff --git a/tools/fuzzer/runners/nanopb_fuzzer_response_test.sh b/tools/fuzzer/runners/nanopb_fuzzer_response_test.sh
index bbcebf11cce59d717f8c11be3b27300084c0d378..97359277ce24dcd0cea1435d757c6a1375d4a5dd 100644
--- a/tools/fuzzer/runners/nanopb_fuzzer_response_test.sh
+++ b/tools/fuzzer/runners/nanopb_fuzzer_response_test.sh
@@ -33,7 +33,7 @@ flags="-max_total_time=$runtime -artifact_prefix=fuzzer_output/ -max_len=128"
 
 if [ "$jobs" != "1" ]
 then
-  flags="-jobs=$jobs -workers=$jobs"
+  flags="-jobs=$jobs -workers=$jobs $flags"
 fi
 
 if [ "$config" == "asan-trace-cmp" ]
diff --git a/tools/fuzzer/runners/nanopb_fuzzer_serverlist_test.sh b/tools/fuzzer/runners/nanopb_fuzzer_serverlist_test.sh
index e9099bac046720aba0569aa0fcdf8d77aeede392..2dfaa2372fc8a99cd9018214d2779e76c2fb1571 100644
--- a/tools/fuzzer/runners/nanopb_fuzzer_serverlist_test.sh
+++ b/tools/fuzzer/runners/nanopb_fuzzer_serverlist_test.sh
@@ -33,7 +33,7 @@ flags="-max_total_time=$runtime -artifact_prefix=fuzzer_output/ -max_len=128"
 
 if [ "$jobs" != "1" ]
 then
-  flags="-jobs=$jobs -workers=$jobs"
+  flags="-jobs=$jobs -workers=$jobs $flags"
 fi
 
 if [ "$config" == "asan-trace-cmp" ]
diff --git a/tools/fuzzer/runners/server_fuzzer.sh b/tools/fuzzer/runners/server_fuzzer.sh
index 28ca8b32719e91fff9cc1c916f229e02472d054a..fc0567f670b72919d9258e454c6de95f827c70b1 100644
--- a/tools/fuzzer/runners/server_fuzzer.sh
+++ b/tools/fuzzer/runners/server_fuzzer.sh
@@ -33,7 +33,7 @@ flags="-max_total_time=$runtime -artifact_prefix=fuzzer_output/ -max_len=2048"
 
 if [ "$jobs" != "1" ]
 then
-  flags="-jobs=$jobs -workers=$jobs"
+  flags="-jobs=$jobs -workers=$jobs $flags"
 fi
 
 if [ "$config" == "asan-trace-cmp" ]
diff --git a/tools/fuzzer/runners/uri_fuzzer_test.sh b/tools/fuzzer/runners/uri_fuzzer_test.sh
index 7dac54ec518051c7588e38acacd5e4566f7c202f..5f33e734654473bfe81b9932d552ad06cb5e353d 100644
--- a/tools/fuzzer/runners/uri_fuzzer_test.sh
+++ b/tools/fuzzer/runners/uri_fuzzer_test.sh
@@ -33,7 +33,7 @@ flags="-max_total_time=$runtime -artifact_prefix=fuzzer_output/ -max_len=128"
 
 if [ "$jobs" != "1" ]
 then
-  flags="-jobs=$jobs -workers=$jobs"
+  flags="-jobs=$jobs -workers=$jobs $flags"
 fi
 
 if [ "$config" == "asan-trace-cmp" ]