diff --git a/pamu2fcfg/pamu2fcfg.c b/pamu2fcfg/pamu2fcfg.c
index 74d6ab4..cbc30a6 100644
--- a/pamu2fcfg/pamu2fcfg.c
+++ b/pamu2fcfg/pamu2fcfg.c
@@ -467,13 +467,13 @@ int main(int argc, char *argv[]) {
   parse_args(argc, argv, &args);
   fido_init(args.debug ? FIDO_DEBUG : 0);
 
-  devlist = fido_dev_info_new(64);
+  devlist = fido_dev_info_new(DEVLIST_LEN);
   if (!devlist) {
     fprintf(stderr, "error: fido_dev_info_new failed\n");
     goto err;
   }
 
-  r = fido_dev_info_manifest(devlist, 64, &ndevs);
+  r = fido_dev_info_manifest(devlist, DEVLIST_LEN, &ndevs);
   if (r != FIDO_OK) {
     fprintf(stderr, "Unable to discover device(s), %s (%d)\n", fido_strerr(r),
             r);
@@ -489,7 +489,7 @@ int main(int argc, char *argv[]) {
       fflush(stderr);
       sleep(FREQUENCY);
 
-      r = fido_dev_info_manifest(devlist, 64, &ndevs);
+      r = fido_dev_info_manifest(devlist, DEVLIST_LEN, &ndevs);
       if (r != FIDO_OK) {
         fprintf(stderr, "\nUnable to discover device(s), %s (%d)",
                 fido_strerr(r), r);
diff --git a/util.c b/util.c
index f3ea20f..10476b2 100644
--- a/util.c
+++ b/util.c
@@ -1155,13 +1155,13 @@ int do_authentication(const cfg_t *cfg, const device_t *devices,
 #endif
   memset(&pk, 0, sizeof(pk));
 
-  devlist = fido_dev_info_new(64);
+  devlist = fido_dev_info_new(DEVLIST_LEN);
   if (!devlist) {
     debug_dbg(cfg, "Unable to allocate devlist");
     goto out;
   }
 
-  r = fido_dev_info_manifest(devlist, 64, &ndevs);
+  r = fido_dev_info_manifest(devlist, DEVLIST_LEN, &ndevs);
   if (r != FIDO_OK) {
     debug_dbg(cfg, "Unable to discover device(s), %s (%d)", fido_strerr(r), r);
     goto out;
@@ -1171,7 +1171,7 @@ int do_authentication(const cfg_t *cfg, const device_t *devices,
 
   debug_dbg(cfg, "Device max index is %zu", ndevs);
 
-  authlist = calloc(64 + 1, sizeof(fido_dev_t *));
+  authlist = calloc(DEVLIST_LEN + 1, sizeof(fido_dev_t *));
   if (!authlist) {
     debug_dbg(cfg, "Unable to allocate authenticator list");
     goto out;
@@ -1267,13 +1267,13 @@ int do_authentication(const cfg_t *cfg, const device_t *devices,
 
     fido_dev_info_free(&devlist, ndevs);
 
-    devlist = fido_dev_info_new(64);
+    devlist = fido_dev_info_new(DEVLIST_LEN);
     if (!devlist) {
       debug_dbg(cfg, "Unable to allocate devlist");
       goto out;
     }
 
-    r = fido_dev_info_manifest(devlist, 64, &ndevs);
+    r = fido_dev_info_manifest(devlist, DEVLIST_LEN, &ndevs);
     if (r != FIDO_OK) {
       debug_dbg(cfg, "Unable to discover device(s), %s (%d)", fido_strerr(r),
                 r);
diff --git a/util.h b/util.h
index cb8572b..f3dac94 100644
--- a/util.h
+++ b/util.h
@@ -21,6 +21,8 @@
 #define DEFAULT_ORIGIN_PREFIX "pam://"
 #define SSH_ORIGIN "ssh:"
 
+#define DEVLIST_LEN 64
+
 typedef struct {
   unsigned max_devs;
   int manual;