diff --git a/bindgen-citro3d/Cargo.toml b/bindgen-citro3d/Cargo.toml
index 3231842..86ac6e5 100644
--- a/bindgen-citro3d/Cargo.toml
+++ b/bindgen-citro3d/Cargo.toml
@@ -2,6 +2,7 @@
 name = "bindgen-citro3d"
 version = "0.1.0"
 edition = "2021"
+description = "Helper tool to generate citro3d-sys bindings."
 
 [dependencies]
 bindgen = "0.62.0"
diff --git a/bindgen-citro3d/src/main.rs b/bindgen-citro3d/src/main.rs
index 6d1282b..ea12c12 100644
--- a/bindgen-citro3d/src/main.rs
+++ b/bindgen-citro3d/src/main.rs
@@ -1,3 +1,7 @@
+//! This is meant to be run as a "script" to generate bindings to `citro3d`.
+//! We use this instead of `bindgen-cli` to enable the use of [`CustomCallbacks`]
+//! with [`bindgen`] as a library for finer grained control of the bindings.
+
 use std::iter::FromIterator;
 use std::path::PathBuf;
 
@@ -8,7 +12,7 @@ fn main() {
     let devkitpro = std::env::var("DEVKITPRO").expect("DEVKITPRO not set in environment");
     let devkitarm = std::env::var("DEVKITARM").expect("DEVKITARM not set in environment");
 
-    let include_path = PathBuf::from(devkitpro).join(PathBuf::from_iter(["libctru", "include"]));
+    let include_path = PathBuf::from_iter([devkitpro.as_str(), "libctru", "include"]);
     let header = include_path.join("tex3ds.h");
 
     let sysroot = PathBuf::from(devkitarm).join("arm-none-eabi");
@@ -25,13 +29,13 @@ fn main() {
         .fit_macro_constants(true)
         .raw_line("use ctru_sys::*;")
         .must_use_type("Result")
-        // TODO functions,types,vars
         .blocklist_type("u(8|16|32|64)")
         .opaque_type("(GPU|GFX)_.*")
         .opaque_type("float24Uniform_s")
-        .blocklist_file(".*/3ds/.*[.]h")
         .allowlist_file(".*/c3d/.*[.]h")
         .allowlist_file(".*/tex3ds[.]h")
+        .blocklist_file(".*/3ds/.*[.]h")
+        .blocklist_file(".*/sys/.*[.]h")
         .clang_args([
             "--target=arm-none-eabi",
             "--sysroot",
@@ -57,6 +61,14 @@ fn main() {
         .expect("failed to write bindings");
 }
 
+/// Custom callback struct to allow us to mark some "known good types" as
+/// [`Copy`], which in turn allows using Rust `union` instead of bindgen union
+/// types. See
+/// <https://rust-lang.github.io/rust-bindgen/using-unions.html#which-union-type-will-bindgen-generate>
+/// for more info.
+///
+/// We do the same for [`Debug`] just for the convenience of derived Debug impls
+/// on some `citro3d` types.
 #[derive(Debug)]
 struct CustomCallbacks;
 
diff --git a/citro3d-sys/build.rs b/citro3d-sys/build.rs
index ff80359..e865214 100644
--- a/citro3d-sys/build.rs
+++ b/citro3d-sys/build.rs
@@ -6,7 +6,7 @@ fn main() {
 
     println!("cargo:rerun-if-changed=build.rs");
     println!("cargo:rerun-if-env-changed=DEVKITPRO");
-    println!("cargo:rustc-link-search=native={}/libctru/lib", dkp_path);
+    println!("cargo:rustc-link-search=native={dkp_path}/libctru/lib");
     println!(
         "cargo:rustc-link-lib=static={}",
         match debug_symbols.as_str() {
diff --git a/citro3d-sys/src/bindings.rs b/citro3d-sys/src/bindings.rs
index c6fc58e..76ca7ad 100644
--- a/citro3d-sys/src/bindings.rs
+++ b/citro3d-sys/src/bindings.rs
@@ -92,210 +92,9 @@ pub const C3D_DEFAULT_CMDBUF_SIZE: u32 = 262144;
 pub const C3DF_LightEnv_IsCP_Any: u32 = 66846720;
 pub const C3DF_LightEnv_LutDirtyAll: u32 = 4227858432;
 pub type __int64_t = ::libc::c_longlong;
-pub type _LOCK_T = i32;
-#[repr(C)]
-#[derive(Debug, Copy, Clone)]
-pub struct __lock_t {
-    pub lock: _LOCK_T,
-    pub thread_tag: u32,
-    pub counter: u32,
-}
-pub type _LOCK_RECURSIVE_T = __lock_t;
 pub type _off_t = __int64_t;
 pub type _fpos_t = __int64_t;
 pub type wint_t = ::libc::c_int;
-#[repr(C)]
-#[derive(Copy, Clone)]
-pub struct _mbstate_t {
-    pub __count: ::libc::c_int,
-    pub __value: _mbstate_t__bindgen_ty_1,
-}
-#[repr(C)]
-#[derive(Copy, Clone)]
-pub union _mbstate_t__bindgen_ty_1 {
-    pub __wch: wint_t,
-    pub __wchb: [::libc::c_uchar; 4usize],
-}
-pub type __ULong = ::libc::c_ulong;
-pub type _flock_t = _LOCK_RECURSIVE_T;
-#[repr(C)]
-#[derive(Debug, Copy, Clone)]
-pub struct __locale_t {
-    _unused: [u8; 0],
-}
-#[repr(C)]
-#[derive(Debug, Copy, Clone)]
-pub struct _Bigint {
-    pub _next: *mut _Bigint,
-    pub _k: ::libc::c_int,
-    pub _maxwds: ::libc::c_int,
-    pub _sign: ::libc::c_int,
-    pub _wds: ::libc::c_int,
-    pub _x: [__ULong; 1usize],
-}
-#[repr(C)]
-#[derive(Debug, Copy, Clone)]
-pub struct __tm {
-    pub __tm_sec: ::libc::c_int,
-    pub __tm_min: ::libc::c_int,
-    pub __tm_hour: ::libc::c_int,
-    pub __tm_mday: ::libc::c_int,
-    pub __tm_mon: ::libc::c_int,
-    pub __tm_year: ::libc::c_int,
-    pub __tm_wday: ::libc::c_int,
-    pub __tm_yday: ::libc::c_int,
-    pub __tm_isdst: ::libc::c_int,
-}
-#[repr(C)]
-#[derive(Debug, Copy, Clone)]
-pub struct _on_exit_args {
-    pub _fnargs: [*mut ::libc::c_void; 32usize],
-    pub _dso_handle: [*mut ::libc::c_void; 32usize],
-    pub _fntypes: __ULong,
-    pub _is_cxa: __ULong,
-}
-#[repr(C)]
-#[derive(Debug, Copy, Clone)]
-pub struct _atexit {
-    pub _next: *mut _atexit,
-    pub _ind: ::libc::c_int,
-    pub _fns: [::core::option::Option<unsafe extern "C" fn()>; 32usize],
-    pub _on_exit_args: _on_exit_args,
-}
-#[repr(C)]
-#[derive(Debug, Copy, Clone)]
-pub struct __sbuf {
-    pub _base: *mut ::libc::c_uchar,
-    pub _size: ::libc::c_int,
-}
-#[repr(C)]
-#[derive(Copy, Clone)]
-pub struct __sFILE {
-    pub _p: *mut ::libc::c_uchar,
-    pub _r: ::libc::c_int,
-    pub _w: ::libc::c_int,
-    pub _flags: ::libc::c_short,
-    pub _file: ::libc::c_short,
-    pub _bf: __sbuf,
-    pub _lbfsize: ::libc::c_int,
-    pub _cookie: *mut ::libc::c_void,
-    pub _read: ::core::option::Option<
-        unsafe extern "C" fn(
-            arg1: *mut _reent,
-            arg2: *mut ::libc::c_void,
-            arg3: *mut ::libc::c_char,
-            arg4: ::libc::c_int,
-        ) -> ::libc::c_int,
-    >,
-    pub _write: ::core::option::Option<
-        unsafe extern "C" fn(
-            arg1: *mut _reent,
-            arg2: *mut ::libc::c_void,
-            arg3: *const ::libc::c_char,
-            arg4: ::libc::c_int,
-        ) -> ::libc::c_int,
-    >,
-    pub _seek: ::core::option::Option<
-        unsafe extern "C" fn(
-            arg1: *mut _reent,
-            arg2: *mut ::libc::c_void,
-            arg3: _fpos_t,
-            arg4: ::libc::c_int,
-        ) -> _fpos_t,
-    >,
-    pub _close: ::core::option::Option<
-        unsafe extern "C" fn(arg1: *mut _reent, arg2: *mut ::libc::c_void) -> ::libc::c_int,
-    >,
-    pub _ub: __sbuf,
-    pub _up: *mut ::libc::c_uchar,
-    pub _ur: ::libc::c_int,
-    pub _ubuf: [::libc::c_uchar; 3usize],
-    pub _nbuf: [::libc::c_uchar; 1usize],
-    pub _lb: __sbuf,
-    pub _blksize: ::libc::c_int,
-    pub _offset: _off_t,
-    pub _data: *mut _reent,
-    pub _lock: _flock_t,
-    pub _mbstate: _mbstate_t,
-    pub _flags2: ::libc::c_int,
-}
-pub type __FILE = __sFILE;
-#[repr(C)]
-#[derive(Debug, Copy, Clone)]
-pub struct _glue {
-    pub _next: *mut _glue,
-    pub _niobs: ::libc::c_int,
-    pub _iobs: *mut __FILE,
-}
-#[repr(C)]
-#[derive(Debug, Copy, Clone)]
-pub struct _rand48 {
-    pub _seed: [::libc::c_ushort; 3usize],
-    pub _mult: [::libc::c_ushort; 3usize],
-    pub _add: ::libc::c_ushort,
-}
-#[repr(C)]
-#[derive(Copy, Clone)]
-pub struct _reent {
-    pub _errno: ::libc::c_int,
-    pub _stdin: *mut __FILE,
-    pub _stdout: *mut __FILE,
-    pub _stderr: *mut __FILE,
-    pub _inc: ::libc::c_int,
-    pub _emergency: [::libc::c_char; 25usize],
-    pub _unspecified_locale_info: ::libc::c_int,
-    pub _locale: *mut __locale_t,
-    pub __sdidinit: ::libc::c_int,
-    pub __cleanup: ::core::option::Option<unsafe extern "C" fn(arg1: *mut _reent)>,
-    pub _result: *mut _Bigint,
-    pub _result_k: ::libc::c_int,
-    pub _p5s: *mut _Bigint,
-    pub _freelist: *mut *mut _Bigint,
-    pub _cvtlen: ::libc::c_int,
-    pub _cvtbuf: *mut ::libc::c_char,
-    pub _new: _reent__bindgen_ty_1,
-    pub _atexit: *mut _atexit,
-    pub _atexit0: _atexit,
-    pub _sig_func: *mut ::core::option::Option<unsafe extern "C" fn(arg1: ::libc::c_int)>,
-    pub __sglue: _glue,
-    pub __sf: [__FILE; 3usize],
-    pub deviceData: *mut ::libc::c_void,
-}
-#[repr(C)]
-#[derive(Copy, Clone)]
-pub union _reent__bindgen_ty_1 {
-    pub _reent: _reent__bindgen_ty_1__bindgen_ty_1,
-    pub _unused: _reent__bindgen_ty_1__bindgen_ty_2,
-}
-#[repr(C)]
-#[derive(Copy, Clone)]
-pub struct _reent__bindgen_ty_1__bindgen_ty_1 {
-    pub _unused_rand: ::libc::c_uint,
-    pub _strtok_last: *mut ::libc::c_char,
-    pub _asctime_buf: [::libc::c_char; 26usize],
-    pub _localtime_buf: __tm,
-    pub _gamma_signgam: ::libc::c_int,
-    pub _rand_next: ::libc::c_ulonglong,
-    pub _r48: _rand48,
-    pub _mblen_state: _mbstate_t,
-    pub _mbtowc_state: _mbstate_t,
-    pub _wctomb_state: _mbstate_t,
-    pub _l64a_buf: [::libc::c_char; 8usize],
-    pub _signal_buf: [::libc::c_char; 24usize],
-    pub _getdate_err: ::libc::c_int,
-    pub _mbrlen_state: _mbstate_t,
-    pub _mbrtowc_state: _mbstate_t,
-    pub _mbsrtowcs_state: _mbstate_t,
-    pub _wcrtomb_state: _mbstate_t,
-    pub _wcsrtombs_state: _mbstate_t,
-    pub _h_errno: ::libc::c_int,
-}
-#[repr(C)]
-#[derive(Debug, Copy, Clone)]
-pub struct _reent__bindgen_ty_1__bindgen_ty_2 {
-    pub _nextf: [*mut ::libc::c_uchar; 30usize],
-    pub _nmalloc: [::libc::c_uint; 30usize],
-}
 pub type C3D_IVec = u32_;
 #[doc = " @struct C3D_FVec"]
 #[doc = " @brief Float vector"]