diff --git a/Cargo.lock b/Cargo.lock
index 79faf45a..2ecedf26 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -19,7 +19,7 @@ dependencies = [
  "arrayvec",
  "blobby",
  "bytes",
- "crypto-common 0.2.0-pre.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crypto-common 0.2.0-pre.4",
  "heapless",
 ]
 
@@ -136,7 +136,7 @@ version = "0.11.0-pre.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0edadbde8e0243b49d434f9a23ec0590af201f400a34d7d51049284e4a77c568"
 dependencies = [
- "crypto-common 0.2.0-pre.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crypto-common 0.2.0-pre.4",
  "zeroize",
 ]
 
@@ -226,7 +226,7 @@ name = "cipher"
 version = "0.5.0-pre.2"
 dependencies = [
  "blobby",
- "crypto-common 0.2.0-pre.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crypto-common 0.2.0-pre.4",
  "inout 0.2.0-pre.4",
  "zeroize",
 ]
@@ -341,17 +341,6 @@ dependencies = [
  "rand_core 0.6.4",
 ]
 
-[[package]]
-name = "crypto-common"
-version = "0.2.0-pre.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "806e4e3731d44f1340b069551225b44c2056c105cad9e67f0c46266db8a3a6b9"
-dependencies = [
- "getrandom",
- "hybrid-array",
- "rand_core 0.6.4",
-]
-
 [[package]]
 name = "crypto-mac"
 version = "0.11.0"
@@ -450,23 +439,11 @@ dependencies = [
  "blobby",
  "block-buffer 0.11.0-pre.4",
  "const-oid 0.10.0-pre.2",
- "crypto-common 0.2.0-pre.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crypto-common 0.2.0-pre.4",
  "subtle",
  "zeroize",
 ]
 
-[[package]]
-name = "digest"
-version = "0.11.0-pre.7"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "957713a19ffdda287c63772e607f848512f67ba948f17d8e42cb8d50fd98a786"
-dependencies = [
- "block-buffer 0.11.0-pre.4",
- "const-oid 0.10.0-pre.2",
- "crypto-common 0.2.0-pre.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "subtle",
-]
-
 [[package]]
 name = "dunce"
 version = "1.0.4"
@@ -546,7 +523,7 @@ dependencies = [
  "base16ct 0.2.0",
  "base64ct",
  "crypto-bigint 0.6.0-pre.12",
- "digest 0.11.0-pre.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "digest 0.11.0-pre.7",
  "ff 0.13.0",
  "group 0.13.0",
  "hex-literal",
@@ -751,7 +728,7 @@ version = "0.13.0-pre.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1fac01891f12d968a2737928c9af2532abdc750e56a890fdbcafdfff17017678"
 dependencies = [
- "digest 0.11.0-pre.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "digest 0.11.0-pre.7",
 ]
 
 [[package]]
@@ -1216,7 +1193,7 @@ checksum = "e18b939d4051b69874cbdb8f55de6a14ae44b357ccb94bdbd0a2122f8f875a46"
 dependencies = [
  "cfg-if",
  "cpufeatures",
- "digest 0.11.0-pre.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "digest 0.11.0-pre.7",
 ]
 
 [[package]]
@@ -1225,7 +1202,7 @@ version = "0.11.0-pre.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9cecb44e361133b3304a1b3e325a1d8c999339fec8c19762b55e1509a17d6806"
 dependencies = [
- "digest 0.11.0-pre.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "digest 0.11.0-pre.7",
  "keccak",
 ]
 
@@ -1252,7 +1229,7 @@ dependencies = [
 name = "signature"
 version = "2.3.0-pre.2"
 dependencies = [
- "digest 0.11.0-pre.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "digest 0.11.0-pre.7",
  "hex-literal",
  "rand_core 0.6.4",
  "sha2 0.11.0-pre.2",
@@ -1352,7 +1329,7 @@ dependencies = [
 name = "universal-hash"
 version = "0.6.0-pre"
 dependencies = [
- "crypto-common 0.2.0-pre.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crypto-common 0.2.0-pre.4",
  "subtle",
 ]
 
diff --git a/Cargo.toml b/Cargo.toml
index e1fa03b8..354080ca 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -16,4 +16,6 @@ members = [
 ]
 
 [patch.crates-io]
+crypto-common = { path = "./crypto-common" }
+digest = { path = "./digest" }
 signature = { path = "./signature" }
diff --git a/crypto-common/src/serializable_state.rs b/crypto-common/src/hazmat.rs
similarity index 100%
rename from crypto-common/src/serializable_state.rs
rename to crypto-common/src/hazmat.rs
diff --git a/crypto-common/src/lib.rs b/crypto-common/src/lib.rs
index bdaff2cd..45ee0553 100644
--- a/crypto-common/src/lib.rs
+++ b/crypto-common/src/lib.rs
@@ -12,6 +12,9 @@
 #[cfg(feature = "std")]
 extern crate std;
 
+/// Hazardous materials.
+pub mod hazmat;
+
 #[cfg(feature = "getrandom")]
 pub use getrandom;
 #[cfg(feature = "rand_core")]
@@ -29,12 +32,6 @@ use hybrid_array::{
 #[cfg(feature = "rand_core")]
 use rand_core::CryptoRngCore;
 
-mod serializable_state;
-pub use serializable_state::{
-    AddSerializedStateSize, DeserializeStateError, SerializableState, SerializedState,
-    SubSerializedStateSize,
-};
-
 /// Block on which [`BlockSizeUser`] implementors operate.
 pub type Block<B> = Array<u8, <B as BlockSizeUser>::BlockSize>;
 
diff --git a/digest/src/core_api/ct_variable.rs b/digest/src/core_api/ct_variable.rs
index fe3aa86c..fe917bfd 100644
--- a/digest/src/core_api/ct_variable.rs
+++ b/digest/src/core_api/ct_variable.rs
@@ -14,9 +14,9 @@ use core::{
 };
 use crypto_common::{
     array::{Array, ArraySize},
+    hazmat::{DeserializeStateError, SerializableState, SerializedState, SubSerializedStateSize},
     typenum::{IsLess, IsLessOrEqual, Le, LeEq, NonZero, Sum, U1, U256},
-    Block, BlockSizeUser, DeserializeStateError, OutputSizeUser, SerializableState,
-    SerializedState, SubSerializedStateSize,
+    Block, BlockSizeUser, OutputSizeUser,
 };
 
 /// Dummy type used with [`CtVariableCoreWrapper`] in cases when
diff --git a/digest/src/core_api/rt_variable.rs b/digest/src/core_api/rt_variable.rs
index c9631e92..ccbb563a 100644
--- a/digest/src/core_api/rt_variable.rs
+++ b/digest/src/core_api/rt_variable.rs
@@ -9,11 +9,11 @@ use core::{
     fmt,
     ops::{Add, Sub},
 };
-use crypto_common::SubSerializedStateSize;
 use crypto_common::{
     array::{Array, ArraySize},
+    hazmat::{DeserializeStateError, SerializableState, SerializedState, SubSerializedStateSize},
     typenum::{Diff, IsLess, Le, NonZero, Sum, Unsigned, U1, U256},
-    AddBlockSize, DeserializeStateError, SerializableState, SerializedState, SubBlockSize,
+    AddBlockSize, SubBlockSize,
 };
 #[cfg(feature = "zeroize")]
 use zeroize::ZeroizeOnDrop;
diff --git a/digest/src/core_api/wrapper.rs b/digest/src/core_api/wrapper.rs
index fc3ca9d9..32b8a5a1 100644
--- a/digest/src/core_api/wrapper.rs
+++ b/digest/src/core_api/wrapper.rs
@@ -13,9 +13,9 @@ use core::{
 };
 use crypto_common::{
     array::{Array, ArraySize},
+    hazmat::{DeserializeStateError, SerializableState, SerializedState, SubSerializedStateSize},
     typenum::{Diff, IsLess, Le, NonZero, Sum, U1, U256},
-    BlockSizeUser, DeserializeStateError, InvalidLength, Key, KeyInit, KeySizeUser, Output,
-    SerializableState, SerializedState, SubSerializedStateSize,
+    BlockSizeUser, InvalidLength, Key, KeyInit, KeySizeUser, Output,
 };
 
 #[cfg(feature = "mac")]