diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index a9b2998..72e43da 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -28,7 +28,6 @@ jobs:
         if: matrix.rust == '1.56'
         run: |
           cargo update -p libc --precise 0.2.163
-          cargo update -p windows-sys --precise 0.52.0
       - name: Setup cache
         uses: Swatinem/rust-cache@v2
       - name: Test (no features)
diff --git a/Cargo.toml b/Cargo.toml
index f3f5ce0..25c1452 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,20 +12,7 @@ description = "Cross-platform interface to the `errno` variable."
 categories = ["no-std", "os"]
 rust-version = "1.56"
 
-[target.'cfg(unix)'.dependencies]
-libc = { version = "0.2", default-features = false }
-
-[target.'cfg(windows)'.dependencies.windows-sys]
-version = ">=0.52, <0.62"
-features = [
-  "Win32_Foundation",
-  "Win32_System_Diagnostics_Debug",
-]
-
-[target.'cfg(target_os="wasi")'.dependencies]
-libc = { version = "0.2", default-features = false }
-
-[target.'cfg(target_os="hermit")'.dependencies]
+[target.'cfg(any(unix, target_os="wasi", target_os="hermit"))'.dependencies]
 libc = { version = "0.2", default-features = false }
 
 [features]
diff --git a/src/windows.rs b/src/windows.rs
index 9c7c0e4..88e49c3 100644
--- a/src/windows.rs
+++ b/src/windows.rs
@@ -15,13 +15,36 @@
 use core::char::{self, REPLACEMENT_CHARACTER};
 use core::ptr;
 use core::str;
-use windows_sys::Win32::Foundation::{GetLastError, SetLastError, WIN32_ERROR};
-use windows_sys::Win32::System::Diagnostics::Debug::{
-    FormatMessageW, FORMAT_MESSAGE_FROM_SYSTEM, FORMAT_MESSAGE_IGNORE_INSERTS,
-};
 
 use crate::Errno;
 
+/// Insert sequences in the message definition such as %1 are to be ignored and passed through to the output buffer unchanged.
+///
+/// This flag is useful for fetching a message for later formatting. If this flag is set, the `arguments` parameter is ignored.
+const FORMAT_MESSAGE_IGNORE_INSERTS: u32 = 512;
+/// The function should search the system message-table resource(s) for the requested message.
+///
+/// If this flag is specified, an application can pass the result of the GetLastError function to retrieve the message text for a system-defined error.
+const FORMAT_MESSAGE_FROM_SYSTEM: u32 = 4096;
+
+#[link(name = "kernel32")]
+extern "system" {
+    /// <https://learn.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-formatmessagew>
+    fn FormatMessageW(
+        flags: u32,
+        source: *const core::ffi::c_void,
+        message_id: u32,
+        language_id: u32,
+        buffer: *mut u16,
+        size: u32,
+        arguments: *const *const i8,
+    ) -> u32;
+    /// <https://learn.microsoft.com/en-us/windows/win32/api/errhandlingapi/nf-errhandlingapi-getlasterror>
+    fn GetLastError() -> u32;
+    /// <https://learn.microsoft.com/en-us/windows/win32/api/errhandlingapi/nf-errhandlingapi-setlasterror>
+    fn SetLastError(err_code: u32);
+}
+
 fn from_utf16_lossy<'a>(input: &[u16], output: &'a mut [u8]) -> &'a str {
     let mut output_len = 0;
     for c in char::decode_utf16(input.iter().copied().take_while(|&x| x != 0))
@@ -77,5 +100,5 @@ pub fn errno() -> Errno {
 }
 
 pub fn set_errno(Errno(errno): Errno) {
-    unsafe { SetLastError(errno as WIN32_ERROR) }
+    unsafe { SetLastError(errno as u32) }
 }