Ruby modules actually do something

rootfs/boot/grub/grub.cfg

@@ -2,4 +2,5 @@ set timeout=0
 
 menuentry "mrubyvisor" {
     multiboot2 /boot/mrubyvisor.multiboot2
+    module2 /boot/hello.rb
 }

rootfs/boot/hello.rb

@@ -0,0 +1 @@
+console_puts 'Hello, World! Ruby modules work!'

src/main.c

@@ -34,6 +34,8 @@ static void *my_realloc(void *ptr, size_t size);
 
 static bool load_module(const char *source, size_t size, const char *cmdline);
 
+static mrb_value ruby_console_puts(mrb_state *mrb, mrb_value self);
+
 void main(
     const uint32_t multiboot2_info_magic,
     const struct KernAux_Multiboot2_Info *const multiboot2_info
@@ -53,6 +55,15 @@ void main(
     ASSERT(mrb = mrb_open());
     ASSERT(context = mrbc_context_new(mrb));
 
+    // Define method Kernel#console_puts
+    mrb_define_method(
+        mrb,
+        mrb->kernel_module,
+        "console_puts",
+        ruby_console_puts,
+        MRB_ARGS_REQ(1)
+    );
+
     for (
         const struct KernAux_Multiboot2_ITag_Module *module_tag =
             (const struct KernAux_Multiboot2_ITag_Module*)
@@ -125,3 +136,13 @@ bool load_module(
     mrb_gc_arena_restore(mrb, arena);
     return status;
 }
+
+mrb_value ruby_console_puts(
+    mrb_state *const mrb,
+    mrb_value self __attribute__((unused))
+) {
+    const char *str = NULL;
+    mrb_get_args(mrb, "z", &str);
+    kernaux_drivers_console_puts(str);
+    return mrb_nil_value();
+}