diff --git a/Cargo.lock b/Cargo.lock
index e9a0cdc5..d9da80ad 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -150,18 +150,6 @@ version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
 
-[[package]]
-name = "blake2"
-version = "0.8.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "94cb07b0da6a73955f8fb85d24c466778e70cda767a568229b104f0264089330"
-dependencies = [
- "byte-tools",
- "crypto-mac",
- "digest",
- "opaque-debug",
-]
-
 [[package]]
 name = "blake2b_simd"
 version = "0.5.10"
@@ -200,7 +188,7 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "20c116dad307b68138cc2e2f3a699c16f52faa47c65f98fc6de1dea9a097ee1e"
 dependencies = [
- "subtle 2.2.2",
+ "subtle",
 ]
 
 [[package]]
@@ -322,16 +310,6 @@ dependencies = [
  "lazy_static",
 ]
 
-[[package]]
-name = "crypto-mac"
-version = "0.7.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4434400df11d95d556bac068ddfedd482915eb18fe8bea89bc80b6e4b1c179e5"
-dependencies = [
- "generic-array",
- "subtle 1.0.0",
-]
-
 [[package]]
 name = "curve25519-dalek"
 version = "2.0.0"
@@ -341,7 +319,7 @@ dependencies = [
  "byteorder",
  "digest",
  "rand_core 0.5.1",
- "subtle 2.2.2",
+ "subtle",
  "zeroize",
 ]
 
@@ -725,7 +703,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "aaacc6b2b5fa79a5bd49de8439534b1f98886f06b88da02afeb968d60678b978"
 dependencies = [
  "bls12_381",
- "subtle 2.2.2",
+ "subtle",
 ]
 
 [[package]]
@@ -1598,12 +1576,6 @@ version = "0.9.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6446ced80d6c486436db5c078dde11a9f73d42b57fb273121e160b84f63d894c"
 
-[[package]]
-name = "subtle"
-version = "1.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2d67a5a62ba6e01cb2192ff309324cb4875d0c451d55fe2319433abe7a05a8ee"
-
 [[package]]
 name = "subtle"
 version = "2.2.2"
@@ -2076,13 +2048,14 @@ dependencies = [
 name = "zebra-chain"
 version = "0.1.0"
 dependencies = [
- "blake2",
+ "blake2b_simd",
  "bs58",
  "byteorder",
  "chrono",
  "ed25519-zebra",
  "futures",
  "hex",
+ "jubjub",
  "lazy_static",
  "proptest",
  "proptest-derive",
diff --git a/zebra-chain/Cargo.toml b/zebra-chain/Cargo.toml
index a075e8b5..316ad68f 100644
--- a/zebra-chain/Cargo.toml
+++ b/zebra-chain/Cargo.toml
@@ -8,12 +8,13 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-blake2 = "0.8.1"
+blake2b_simd = "0.5.10"
 bs58 = { version = "0.3", features = ["check"] }
 byteorder = "1.3"
 chrono = "0.4"
 futures = "0.3"
 hex = "0.4"
+jubjub = "0.3.0"
 lazy_static = "1.4.0"
 rand_core = "0.5.1"
 ripemd160 = "0.8.0"
diff --git a/zebra-chain/src/keys/sapling.rs b/zebra-chain/src/keys/sapling.rs
index 00aa31f5..40280811 100644
--- a/zebra-chain/src/keys/sapling.rs
+++ b/zebra-chain/src/keys/sapling.rs
@@ -9,7 +9,8 @@
 
 use std::fmt;
 
-use blake2::{Blake2b, Digest};
+use blake2b_simd;
+use jubjub;
 use rand_core::{CryptoRng, RngCore};
 
 #[cfg(test)]