--- a/src/types.rs	Mon Feb 17 10:39:34 2020 +0100
+++ b/src/types.rs	Sun Feb 16 11:17:38 2020 +0100
@@ -4,7 +4,10 @@
 
 use std::cell::RefCell;
 use std::fs::File;
+#[cfg(unix)]
 use std::os::unix::fs::FileExt;
+#[cfg(windows)]
+use std::os::windows::fs::FileExt;
 use std::rc::Rc;
 
 pub trait RandomAccess {
@@ -31,12 +34,20 @@
     }
 }
 
+#[cfg(unix)]
 impl RandomAccess for File {
     fn read_at(&self, off: usize, dst: &mut [u8]) -> Result<usize> {
         Ok((self as &dyn FileExt).read_at(dst, off as u64)?)
     }
 }
 
+#[cfg(windows)]
+impl RandomAccess for File {
+    fn read_at(&self, off: usize, dst: &mut [u8]) -> Result<usize> {
+        Ok((self as &dyn FileExt).seek_read(dst, off as u64)?)
+    }
+}
+
 /// A shared thingy with interior mutability.
 pub type Shared<T> = Rc<RefCell<T>>;