diff --git a/Cargo.toml b/Cargo.toml
index ae2bd8f..e0ba956 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -16,7 +16,7 @@ exclude = [ ".gitignore", "TESTVECTORS", "res/*" ]
 travis-ci = { repository = "dalek-cryptography/ed25519-dalek", branch = "master"}
 
 [dependencies.curve25519-dalek]
-version = "0.20"
+version = "1.0.0-pre.0"
 default-features = false
 
 [dependencies.rand]
@@ -24,19 +24,12 @@ version = "0.5"
 default-features = false
 features = ["i128_support"]
 
-[dependencies.digest]
-version = "^0.7"
-
-[dependencies.generic-array]
-# same version that digest depends on
-version = "0.9"
-
 [dependencies.serde]
 version = "^1.0"
 optional = true
 
 [dependencies.sha2]
-version = "^0.7"
+version = "^0.8"
 optional = true
 
 [dependencies.failure]
@@ -48,7 +41,7 @@ version = "0.2"
 
 [dev-dependencies]
 hex = "^0.3"
-sha2 = "^0.7"
+sha2 = "^0.8"
 bincode = "^0.9"
 criterion = "0.2"
 
diff --git a/src/ed25519.rs b/src/ed25519.rs
index 95898f4..0654eb1 100644
--- a/src/ed25519.rs
+++ b/src/ed25519.rs
@@ -30,9 +30,8 @@ use sha2::Sha512;
 
 use clear_on_drop::clear::Clear;
 
-use digest::Digest;
-
-use generic_array::typenum::U64;
+use curve25519_dalek::digest::Digest;
+use curve25519_dalek::digest::generic_array::typenum::U64;
 
 use curve25519_dalek::constants;
 use curve25519_dalek::edwards::CompressedEdwardsY;
@@ -186,7 +185,9 @@ impl Drop for SecretKey {
 
 impl SecretKey {
     /// Expand this `SecretKey` into an `ExpandedSecretKey`.
-    pub fn expand<D>(&self) -> ExpandedSecretKey where D: Digest<OutputSize = U64> + Default {
+    pub fn expand<D>(&self) -> ExpandedSecretKey
+        where D: Digest<OutputSize = U64> + Default
+    {
         ExpandedSecretKey::from_secret_key::<D>(&self)
     }
 
@@ -556,7 +557,7 @@ impl ExpandedSecretKey {
         let mut upper: [u8; 32] = [0u8; 32];
 
         h.input(secret_key.as_bytes());
-        hash.copy_from_slice(h.fixed_result().as_slice());
+        hash.copy_from_slice(h.result().as_slice());
 
         lower.copy_from_slice(&hash[00..32]);
         upper.copy_from_slice(&hash[32..64]);
@@ -620,7 +621,7 @@ impl ExpandedSecretKey {
                              context: Option<&'static [u8]>) -> Signature
         where D: Digest<OutputSize = U64> + Default
     {
-        let mut h: D = D::default();
+        let mut h: D;
         let mut prehash: [u8; 64] = [0u8; 64];
         let R: CompressedEdwardsY;
         let r: Scalar;
@@ -634,7 +635,7 @@ impl ExpandedSecretKey {
         let ctx_len: u8 = ctx.len() as u8;
 
         // Get the result of the pre-hashed message.
-        prehash.copy_from_slice(prehashed_message.fixed_result().as_slice());
+        prehash.copy_from_slice(prehashed_message.result().as_slice());
 
         // This is the dumbest, ten-years-late, non-admission of fucking up the
         // domain separation I have ever seen.  Why am I still required to put
@@ -648,24 +649,25 @@ impl ExpandedSecretKey {
         //
         // This is a really fucking stupid bandaid, and the damned scheme is
         // still bleeding from malleability, for fuck's sake.
-        h.input(b"SigEd25519 no Ed25519 collisions");
-        h.input(&[1]); // Ed25519ph
-        h.input(&[ctx_len]);
-        h.input(ctx);
-        h.input(&self.nonce);
-        h.input(&prehash);
+        h = D::default()
+            .chain(b"SigEd25519 no Ed25519 collisions")
+            .chain(&[1]) // Ed25519ph
+            .chain(&[ctx_len])
+            .chain(ctx)
+            .chain(&self.nonce)
+            .chain(&prehash[..]);
 
         r = Scalar::from_hash(h);
         R = (&r * &constants::ED25519_BASEPOINT_TABLE).compress();
 
-        h = D::default();
-        h.input(b"SigEd25519 no Ed25519 collisions");
-        h.input(&[1]); // Ed25519ph
-        h.input(&[ctx_len]);
-        h.input(ctx);
-        h.input(R.as_bytes());
-        h.input(public_key.as_bytes());
-        h.input(&prehash);
+        h = D::default()
+            .chain(b"SigEd25519 no Ed25519 collisions")
+            .chain(&[1]) // Ed25519ph
+            .chain(&[ctx_len])
+            .chain(ctx)
+            .chain(R.as_bytes())
+            .chain(public_key.as_bytes())
+            .chain(&prehash[..]);
 
         k = Scalar::from_hash(h);
         s = &(&k * &self.key) + &r;
@@ -784,7 +786,7 @@ impl PublicKey {
         let mut digest: [u8; 32] = [0u8; 32];
 
         h.input(secret_key.as_bytes());
-        hash.copy_from_slice(h.fixed_result().as_slice());
+        hash.copy_from_slice(h.result().as_slice());
 
         digest.copy_from_slice(&hash[..32]);
 
@@ -886,7 +888,7 @@ impl PublicKey {
         h.input(ctx);
         h.input(signature.R.as_bytes());
         h.input(self.as_bytes());
-        h.input(prehashed_message.fixed_result().as_slice());
+        h.input(prehashed_message.result().as_slice());
 
         k = Scalar::from_hash(h);
         R = EdwardsPoint::vartime_double_scalar_mul_basepoint(&k, &(-A), &signature.s);
diff --git a/src/lib.rs b/src/lib.rs
index 1d9bc1f..488ea5c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -258,8 +258,6 @@
 #![deny(missing_docs)] // refuse to compile if documentation is missing
 
 extern crate curve25519_dalek;
-extern crate generic_array;
-extern crate digest;
 extern crate failure;
 extern crate rand;
 extern crate clear_on_drop;