diff --git a/src/common.zig b/src/common.zig
index f259cf0039a3ab4198e44c9a8c4b4cd52d02c624..484bc521e1683d1a42192ad15623874f9a7c0c06 100644
--- a/src/common.zig
+++ b/src/common.zig
@@ -250,7 +250,7 @@ pub fn get_module_from_dep(d: *zigmod.Dep, cachepath: string, options: *CollectO
                     }
                     const moddirO = try std.fs.cwd().openDir(modpath, .{});
                     const tryname = try u.detect_pkgname(options.alloc, d.name, modpath);
-                    const trymain = u.detct_mainfile(options.alloc, d.main, moddirO, tryname) catch |err| switch (err) {
+                    const trymain: ?string = u.detct_mainfile(options.alloc, d.main, moddirO, tryname) catch |err| switch (err) {
                         error.CantFindMain => null,
                         else => |ee| return ee,
                     };