diff --git a/LICENSE-MIT b/LICENSE-MIT
index 1581c90d16..6af13dfaa9 100644
--- a/LICENSE-MIT
+++ b/LICENSE-MIT
@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2017-2019 Electric Coin Company
+Copyright (c) 2017-2022 Electric Coin Company
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/bellman/src/groth16/generator.rs b/bellman/src/groth16/generator.rs
index d04ed6c0a0..a20cc4ceb4 100644
--- a/bellman/src/groth16/generator.rs
+++ b/bellman/src/groth16/generator.rs
@@ -398,8 +398,8 @@ where
                             *b_g2 = g2_wnaf.scalar(&bt);
                         }
 
-                        at.mul_assign(&beta);
-                        bt.mul_assign(&alpha);
+                        at.mul_assign(beta);
+                        bt.mul_assign(alpha);
 
                         let mut e = at;
                         e.add_assign(&bt);
diff --git a/bellman/src/groth16/mod.rs b/bellman/src/groth16/mod.rs
index 7c97197aaa..4fb936bb36 100644
--- a/bellman/src/groth16/mod.rs
+++ b/bellman/src/groth16/mod.rs
@@ -50,7 +50,7 @@ impl<E: Engine> Proof<E> {
             let mut g1_repr = <E::G1Affine as GroupEncoding>::Repr::default();
             reader.read_exact(g1_repr.as_mut())?;
 
-            let affine = E::G1Affine::from_bytes(&g1_repr);
+            let affine = E::G1Affine::from_bytes_unchecked(&g1_repr);
             let affine = if affine.is_some().into() {
                 Ok(affine.unwrap())
             } else {
@@ -73,7 +73,7 @@ impl<E: Engine> Proof<E> {
             let mut g2_repr = <E::G2Affine as GroupEncoding>::Repr::default();
             reader.read_exact(g2_repr.as_mut())?;
 
-            let affine = E::G2Affine::from_bytes(&g2_repr);
+            let affine = E::G2Affine::from_bytes_unchecked(&g2_repr);
             let affine = if affine.is_some().into() {
                 Ok(affine.unwrap())
             } else {
diff --git a/rust-toolchain b/rust-toolchain
index 32b7211cb6..154cb93b2c 100644
--- a/rust-toolchain
+++ b/rust-toolchain
@@ -1 +1 @@
-1.40.0
+1.52.1
diff --git a/zcash_proofs/Cargo.toml b/zcash_proofs/Cargo.toml
index 4a58e9dfbe..ed2de83f94 100644
--- a/zcash_proofs/Cargo.toml
+++ b/zcash_proofs/Cargo.toml
@@ -15,7 +15,7 @@ edition = "2018"
 bellman = { version = "0.6", path = "../bellman", default-features = false, features = ["groth16"] }
 blake2b_simd = "0.5"
 byteorder = "1"
-directories = { version = "1", optional = true }
+directories = { version = "3", optional = true }
 ff = { version = "0.6", path = "../ff" }
 minreq = { version = "2", features = ["https"], optional = true }
 pairing = { version = "0.16", path = "../pairing" }
@@ -26,7 +26,7 @@ zcash_primitives = { version = "0.2", path = "../zcash_primitives" }
 rand_xorshift = "0.2"
 
 [features]
-default = ["local-prover", "multicore"]
+default = ["local-prover"]
 download-params = ["minreq"]
 local-prover = ["directories"]
 multicore = ["bellman/multicore"]
@@ -41,3 +41,6 @@ required-features = ["download-params"]
 
 [badges]
 maintenance = { status = "actively-developed" }
+
+[lib]
+crate-type = ["cdylib", "rlib"]