housekeeping - thx sora

build.zig

@@ -35,10 +35,11 @@ pub fn build(b: *std.Build) void {
         // intend to expose to consumers that were defined in other files part
         // of this module, you will have to make sure to re-export them from
         // the root file.
-        .root_source_file = b.path("src/root.zig"),
+        .root_source_file = b.path("src/main.zig"),
         // Later on we'll use this module as the root module of a test executable
         // which requires us to specify a target.
         .target = target,
+        .optimize = optimize,
     });
 
     // Here we define an executable. An executable needs to have a root module
@@ -59,28 +60,7 @@ pub fn build(b: *std.Build) void {
     // don't need and to put everything under a single module.
     const exe = b.addExecutable(.{
         .name = "aoc25",
-        .root_module = b.createModule(.{
-            // b.createModule defines a new module just like b.addModule but,
-            // unlike b.addModule, it does not expose the module to consumers of
-            // this package, which is why in this case we don't have to give it a name.
-            .root_source_file = b.path("src/main.zig"),
-            // Target and optimization levels must be explicitly wired in when
-            // defining an executable or library (in the root module), and you
-            // can also hardcode a specific target for an executable or library
-            // definition if desireable (e.g. firmware for embedded devices).
-            .target = target,
-            .optimize = optimize,
-            // List of modules available for import in source files part of the
-            // root module.
-            .imports = &.{
-                // Here "aoc25" is the name you will use in your source code to
-                // import this module (e.g. `@import("aoc25")`). The name is
-                // repeated because you are allowed to rename your imports, which
-                // can be extremely useful in case of collisions (which can happen
-                // importing modules from different packages).
-                .{ .name = "aoc25", .module = mod },
-            },
-        }),
+        .root_module = mod,
     });
 
     // This declares intent for the executable to be installed into the