diff --git a/src/args/args.zig b/src/args/args.zig
index a918ef0..bbd6599 100644
--- a/src/args/args.zig
+++ b/src/args/args.zig
@@ -66,7 +66,7 @@ pub fn parseArgs(comptime T: type, allocator: Allocator) !T {
 /// Do not pass the process name as an argument.
 ///
 /// Parsing order of arguments is based on the order they are declared in `T`.
-pub fn parseArgsFromSlice(comptime T: type, allocator: Allocator, args: [][:0]u8) !T {
+pub fn parseArgsFromSlice(comptime T: type, allocator: Allocator, args: []const [:0]const u8) !T {
     var flags = try std.ArrayList(Arg).initCapacity(allocator, 4);
     defer flags.deinit(allocator);
 
diff --git a/src/args/parsers/enumLiteral.zig b/src/args/parsers/enumLiteral.zig
index 5be3166..b731439 100644
--- a/src/args/parsers/enumLiteral.zig
+++ b/src/args/parsers/enumLiteral.zig
@@ -14,9 +14,8 @@ pub fn enumLiteral(comptime T: type) *const fn (value: []const u8) anyerror!T {
 const log = std.log.scoped(.args);
 
 fn parseEnumFromStr(comptime T: type, str: []const u8) !T {
-    const heap_allocator = std.heap.page_allocator;
-    const lower = try std.ascii.allocLowerString(heap_allocator, str);
-    defer heap_allocator.free(lower);
+    var buf: [1024]u8 = undefined;
+    const lower = std.ascii.lowerString(&buf, str);
     const info = @typeInfo(T);
 
     comptime {
@@ -26,8 +25,8 @@ fn parseEnumFromStr(comptime T: type, str: []const u8) !T {
     }
 
     inline for (info.@"enum".fields) |field| {
-        const lower_field_name = try std.ascii.allocLowerString(heap_allocator, field.name);
-        defer heap_allocator.free(lower_field_name);
+        var field_buf: [1024]u8 = undefined;
+        const lower_field_name = std.ascii.lowerString(&field_buf, field.name);
         if (std.mem.eql(u8, lower_field_name, lower)) {
             return @enumFromInt(field.value);
         }
@@ -42,8 +41,8 @@ fn parseEnumFromStr(comptime T: type, str: []const u8) !T {
     log.warn("hint: try one of the following:", .{});
 
     inline for (info.@"enum".fields) |field| {
-        const lower_field_name = try std.ascii.allocLowerString(heap_allocator, field.name);
-        defer heap_allocator.free(lower_field_name);
+        var field_buf: [1024]u8 = undefined;
+        const lower_field_name = std.ascii.lowerString(&field_buf, field.name);
         log.warn("- {s}", .{lower_field_name});
     }