diff --git a/Cargo.lock b/Cargo.lock
index 68f37df22..4fe14d22d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -120,7 +120,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "byte-tools 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "crypto-mac 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "digest 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "digest 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "opaque-debug 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -252,7 +252,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "digest"
-version = "0.8.0"
+version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "generic-array 0.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -541,7 +541,7 @@ version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "block-buffer 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "digest 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "digest 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "opaque-debug 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -1008,7 +1008,7 @@ dependencies = [
  "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "caseless 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "crc 1.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "digest 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "digest 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hexf 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "indexmap 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1144,7 +1144,7 @@ version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "block-buffer 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "digest 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "digest 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fake-simd 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "opaque-debug 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1155,7 +1155,7 @@ version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "block-buffer 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "digest 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "digest 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "fake-simd 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "opaque-debug 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1167,7 +1167,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "block-buffer 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "byte-tools 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "digest 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "digest 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "keccak 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "opaque-debug 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1637,7 +1637,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum crc 1.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d663548de7f5cca343f1e0a48d14dcfb0e9eb4e079ec58883b7251539fa10aeb"
 "checksum crypto-mac 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "4434400df11d95d556bac068ddfedd482915eb18fe8bea89bc80b6e4b1c179e5"
 "checksum diff 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)" = "3c2b69f912779fbb121ceb775d74d51e915af17aaebc38d28a592843a2dd0a3a"
-"checksum digest 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "05f47366984d3ad862010e22c7ce81a7dbcaebbdfb37241a620f8b6596ee135c"
+"checksum digest 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "f3d0c8c8752312f9713efd397ff63acb9f85585afbf179282e720e7704954dd5"
 "checksum dirs 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)" = "3fd78930633bd1c6e35c4b42b1df7b0cbc6bc191146e512bb3bedf243fcc3901"
 "checksum docopt 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7f525a586d310c87df72ebcd98009e57f1cc030c8c268305287a476beb653969"
 "checksum either 1.5.2 (registry+https://github.com/rust-lang/crates.io-index)" = "5527cfe0d098f36e3f8839852688e63c8fff1c90b2b405aef730615f9a7bcf7b"
diff --git a/vm/Cargo.toml b/vm/Cargo.toml
index 74ad46f37..0a1b79c6f 100644
--- a/vm/Cargo.toml
+++ b/vm/Cargo.toml
@@ -6,7 +6,7 @@ edition = "2018"
 
 [dependencies]
 # Crypto:
-digest = "0.8"
+digest = "0.8.1"
 md-5 = "0.8"
 sha-1 = "0.8"
 sha2 = "0.8"
diff --git a/vm/src/stdlib/hashlib.rs b/vm/src/stdlib/hashlib.rs
index c8e38374d..719e3a329 100644
--- a/vm/src/stdlib/hashlib.rs
+++ b/vm/src/stdlib/hashlib.rs
@@ -5,8 +5,6 @@ use crate::obj::objtype::PyClassRef;
 use crate::pyobject::{PyClassImpl, PyObjectRef, PyResult, PyValue};
 use crate::vm::VirtualMachine;
 use std::cell::RefCell;
-// use std::clone::Clone;
-// use std::ops::Deref;
 use std::fmt;
 
 use blake2::{Blake2b, Blake2s};
@@ -79,7 +77,7 @@ impl PyHasher {
     }
 
     fn get_digest(&self) -> Vec<u8> {
-        self.buffer.borrow_mut().get_digest()
+        self.buffer.borrow().get_digest()
     }
 }
 
@@ -201,7 +199,6 @@ pub fn make_module(vm: &VirtualMachine) -> PyObjectRef {
 /// Generic wrapper patching around the hashing libraries.
 struct HashWrapper {
     inner: Box<DynDigest>,
-    data: Vec<u8>,
 }
 
 impl HashWrapper {
@@ -210,10 +207,7 @@ impl HashWrapper {
         D: DynDigest,
         D: Sized,
     {
-        HashWrapper {
-            inner: Box::new(d),
-            data: vec![],
-        }
+        HashWrapper { inner: Box::new(d) }
     }
 
     fn md5() -> Self {
@@ -274,18 +268,15 @@ impl HashWrapper {
     }
 
     fn input(&mut self, data: &[u8]) {
-        // TODO: this is super not efficient. Find a better way for this.
-        self.data.extend(data);
+        self.inner.input(data);
     }
 
     fn digest_size(&self) -> usize {
         self.inner.output_size()
     }
 
-    fn get_digest(&mut self) -> Vec<u8> {
-        // TODO: this is super not efficient. Find a better way for this:
-        self.inner.input(&self.data);
-        let res = self.inner.result_reset().to_vec();
-        res
+    fn get_digest(&self) -> Vec<u8> {
+        let cloned = self.inner.clone();
+        cloned.result().to_vec()
     }
 }