diff --git a/Cargo.toml b/Cargo.toml
index b9c5f7f8..b6a82996 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,11 +12,6 @@ name = "extract"
 test = false
 doc = false
 
-[[bin]]
-name = "cksummer"
-test = false
-doc = false
-
 [[bin]]
 name = "write_sample"
 test = false
diff --git a/src/bin/cksummer.rs b/src/bin/cksummer.rs
deleted file mode 100644
index dcc02ae4..00000000
--- a/src/bin/cksummer.rs
+++ /dev/null
@@ -1,19 +0,0 @@
-extern crate zip;
-
-fn main()
-{
-    let mut stdin = std::io::stdin();
-    let mut crc = 0u32;
-    let mut buf = [0u8, ..4096];
-
-    loop
-    {
-        match stdin.read(&mut buf)
-        {
-            Err(_) => break,
-            Ok(n) => { crc = zip::crc32::crc32(crc, buf.slice_to(n)); },
-        }
-    }
-
-    println!("{:x}", crc);
-}
diff --git a/src/crc32.rs b/src/crc32.rs
index b2578c2c..673a9109 100644
--- a/src/crc32.rs
+++ b/src/crc32.rs
@@ -48,10 +48,10 @@ static CRC32_TABLE : [u32, ..256] = [
 	0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
 ];
 
-/// Update the checksum original based upon the contents of buf.
-pub fn crc32(original: u32, buf: &[u8]) -> u32
+/// Update the checksum prev based upon the contents of buf.
+pub fn update(prev: u32, buf: &[u8]) -> u32
 {
-    let mut crc = original ^ !0u32;
+    let mut crc = prev ^ !0u32;
 
     for byte in buf.iter()
     {
@@ -103,7 +103,7 @@ impl<R: Reader> Reader for Crc32Reader<R>
             },
             Err(e) => return Err(e),
         };
-        self.crc = crc32(self.crc, buf.slice_to(count));
+        self.crc = update(self.crc, buf.slice_to(count));
         Ok(count)
     }
 }
diff --git a/src/lib.rs b/src/lib.rs
index 5632ea47..7f3a7bf8 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -13,7 +13,7 @@ pub use writer::ZipWriter;
 
 mod util;
 mod spec;
-pub mod crc32;
+mod crc32;
 mod reader;
 pub mod types;
 mod writer;
diff --git a/src/writer.rs b/src/writer.rs
index 580f1809..dba838b3 100644
--- a/src/writer.rs
+++ b/src/writer.rs
@@ -1,6 +1,7 @@
 use types;
 use types::ZipFile;
 use spec;
+use crc32;
 use std::default::Default;
 use std::io;
 use std::io::{IoResult, IoError};
@@ -77,7 +78,7 @@ impl ZipWriterStats
 {
     fn update(&mut self, buf: &[u8])
     {
-        self.crc32 = ::crc32::crc32(self.crc32, buf);
+        self.crc32 = crc32::update(self.crc32, buf);
         self.bytes_written += buf.len() as u64;
     }
 }