diff --git a/lib/compiler/Maker/ScannedConfig.zig b/lib/compiler/Maker/ScannedConfig.zig
index 6115e05d629a17ec81348ae0e15770738e30295a..183146af278abe426d194ed932ed83300525b5aa 100644
--- a/lib/compiler/Maker/ScannedConfig.zig
+++ b/lib/compiler/Maker/ScannedConfig.zig
@@ -74,6 +74,11 @@ fn printValue(sc: *const ScannedConfig, s: *Serializer, comptime Field: type, fi
         Configuration.MaxRss => {
             try s.value(field_value.toBytes(), .{});
         },
+        Configuration.Step.Run.Arg.Index => {
+            var sub_struct = try s.beginStruct(.{});
+            try printStruct(sc, &sub_struct, Configuration.Step.Run.Arg, field_value.get(c));
+            try sub_struct.end();
+        },
         else => switch (@typeInfo(Field)) {
             .int => try s.int(field_value),
             .pointer => |info| switch (info.size) {
diff --git a/lib/compiler/configurer.zig b/lib/compiler/configurer.zig
index 538ff6481b2efbe13e232b0e7e9ddb0f11a6fe24..2feac82180f0f9b3df5d65677d2dde5a0133af6c 100644
--- a/lib/compiler/configurer.zig
+++ b/lib/compiler/configurer.zig
@@ -376,7 +376,7 @@ const Serialize = struct {
                         .generated = false,
                         .dep_file = false,
                     },
-                    .prefix = .{ .value = try s.addOptionalString(a.prefix) },
+                    .prefix = .{ .value = if (a.prefix.len != 0) try wc.addString(a.prefix) else null },
                     .suffix = .{ .value = null },
                     .basename = .{ .value = null },
                     .path = .{ .value = null },
@@ -394,7 +394,7 @@ const Serialize = struct {
                         .generated = false,
                         .dep_file = false,
                     },
-                    .prefix = .{ .value = try s.addOptionalString(a.prefix) },
+                    .prefix = .{ .value = if (a.prefix.len != 0) try wc.addString(a.prefix) else null },
                     .suffix = .{ .value = null },
                     .basename = .{ .value = null },
                     .path = .{ .value = try addLazyPath(s, a.lazy_path) },
@@ -412,7 +412,7 @@ const Serialize = struct {
                         .generated = false,
                         .dep_file = false,
                     },
-                    .prefix = .{ .value = try addOptionalString(s, a.prefix) },
+                    .prefix = .{ .value = if (a.prefix.len != 0) try wc.addString(a.prefix) else null },
                     .suffix = .{ .value = try addOptionalString(s, a.suffix) },
                     .basename = .{ .value = null },
                     .path = .{ .value = try addLazyPath(s, a.lazy_path) },
@@ -430,7 +430,7 @@ const Serialize = struct {
                         .generated = false,
                         .dep_file = false,
                     },
-                    .prefix = .{ .value = try addOptionalString(s, a.prefix) },
+                    .prefix = .{ .value = if (a.prefix.len != 0) try wc.addString(a.prefix) else null },
                     .suffix = .{ .value = null },
                     .basename = .{ .value = null },
                     .path = .{ .value = try addLazyPath(s, a.lazy_path) },
@@ -448,7 +448,7 @@ const Serialize = struct {
                         .generated = false,
                         .dep_file = false,
                     },
-                    .prefix = .{ .value = try addOptionalString(s, a) },
+                    .prefix = .{ .value = try wc.addString(a) },
                     .suffix = .{ .value = null },
                     .basename = .{ .value = null },
                     .path = .{ .value = null },
@@ -466,9 +466,9 @@ const Serialize = struct {
                         .generated = true,
                         .dep_file = false,
                     },
-                    .prefix = .{ .value = try addOptionalString(s, a.prefix) },
+                    .prefix = .{ .value = if (a.prefix.len != 0) try wc.addString(a.prefix) else null },
                     .suffix = .{ .value = null },
-                    .basename = .{ .value = try addOptionalString(s, a.basename) },
+                    .basename = .{ .value = if (a.basename.len != 0) try wc.addString(a.basename) else null },
                     .path = .{ .value = null },
                     .producer = .{ .value = null },
                     .generated = .{ .value = a.generated_file },
@@ -484,9 +484,9 @@ const Serialize = struct {
                         .generated = true,
                         .dep_file = false,
                     },
-                    .prefix = .{ .value = try addOptionalString(s, a.prefix) },
+                    .prefix = .{ .value = if (a.prefix.len != 0) try wc.addString(a.prefix) else null },
                     .suffix = .{ .value = null },
-                    .basename = .{ .value = try addOptionalString(s, a.basename) },
+                    .basename = .{ .value = if (a.basename.len != 0) try wc.addString(a.basename) else null },
                     .path = .{ .value = null },
                     .producer = .{ .value = null },
                     .generated = .{ .value = a.generated_file },