diff --git a/.github/workflows/nucypher-core.yml b/.github/workflows/nucypher-core.yml
index d27b2931..1c802a03 100644
--- a/.github/workflows/nucypher-core.yml
+++ b/.github/workflows/nucypher-core.yml
@@ -125,7 +125,7 @@ jobs:
         run: pip install mypy
 
       - name: Run mypy.stubtest
-        run: python -m mypy.stubtest nucypher_core
+        run: python -m mypy.stubtest nucypher_core --allowlist stubtest-allowlist.txt
         working-directory: nucypher-core-python
 
   trigger-wheels:
diff --git a/Cargo.lock b/Cargo.lock
index 1ac07297..c730d786 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -518,7 +518,7 @@ dependencies = [
 [[package]]
 name = "ferveo-common-pre-release"
 version = "0.1.0"
-source = "git+https://github.com/nucypher/ferveo.git#434fd5d07b54e72d120e9aa06cbc3e47848e6bcf"
+source = "git+https://github.com/nucypher/ferveo.git?rev=c3b749732cc2d560240f7a1043c18d10138e30e9#c3b749732cc2d560240f7a1043c18d10138e30e9"
 dependencies = [
  "ark-ec",
  "ark-serialize",
@@ -533,7 +533,7 @@ dependencies = [
 [[package]]
 name = "ferveo-pre-release"
 version = "0.2.0"
-source = "git+https://github.com/nucypher/ferveo.git#434fd5d07b54e72d120e9aa06cbc3e47848e6bcf"
+source = "git+https://github.com/nucypher/ferveo.git?rev=c3b749732cc2d560240f7a1043c18d10138e30e9#c3b749732cc2d560240f7a1043c18d10138e30e9"
 dependencies = [
  "ark-bls12-381",
  "ark-ec",
@@ -636,7 +636,7 @@ dependencies = [
 [[package]]
 name = "group-threshold-cryptography-pre-release"
 version = "0.1.0"
-source = "git+https://github.com/nucypher/ferveo.git#434fd5d07b54e72d120e9aa06cbc3e47848e6bcf"
+source = "git+https://github.com/nucypher/ferveo.git?rev=c3b749732cc2d560240f7a1043c18d10138e30e9#c3b749732cc2d560240f7a1043c18d10138e30e9"
 dependencies = [
  "ark-bls12-381",
  "ark-ec",
@@ -1392,7 +1392,7 @@ checksum = "73473c0e59e6d5812c5dfe2a064a6444949f089e20eec9a2e5506596494e4623"
 [[package]]
 name = "subproductdomain-pre-release"
 version = "0.1.0"
-source = "git+https://github.com/nucypher/ferveo.git#434fd5d07b54e72d120e9aa06cbc3e47848e6bcf"
+source = "git+https://github.com/nucypher/ferveo.git?rev=c3b749732cc2d560240f7a1043c18d10138e30e9#c3b749732cc2d560240f7a1043c18d10138e30e9"
 dependencies = [
  "anyhow",
  "ark-ec",
@@ -1491,7 +1491,7 @@ checksum = "497961ef93d974e23eb6f433eb5fe1b7930b659f06d12dec6fc44a8f554c0bba"
 [[package]]
 name = "umbral-pre"
 version = "0.10.0"
-source = "git+https://github.com/piotr-roslaniec/rust-umbral.git#c7ff41296e26ae0696f84f4a62fd26d619479c52"
+source = "git+https://github.com/piotr-roslaniec/rust-umbral.git?rev=fd2e16f9304b9dab85c9a8947a61d962ff136131#fd2e16f9304b9dab85c9a8947a61d962ff136131"
 dependencies = [
  "base64 0.21.2",
  "chacha20poly1305",
diff --git a/nucypher-core-python/Cargo.toml b/nucypher-core-python/Cargo.toml
index 7aae50fd..0130c80f 100644
--- a/nucypher-core-python/Cargo.toml
+++ b/nucypher-core-python/Cargo.toml
@@ -10,8 +10,8 @@ crate-type = ["cdylib"]
 [dependencies]
 pyo3 = "0.18"
 nucypher-core = { path = "../nucypher-core" }
-umbral-pre = { version = "0.10.0", features = ["bindings-python"], git = "https://github.com/piotr-roslaniec/rust-umbral.git", ref = "4b28a85c494e4e2640abb131460da0680a74134d" }
-ferveo = { package = "ferveo-pre-release", features = ["bindings-python"], git = "https://github.com/nucypher/ferveo.git", ref = "fbb97be59d991a263233a0b876da982143b2cbf2" }
+umbral-pre = { version = "0.10.0", features = ["bindings-python"], git = "https://github.com/piotr-roslaniec/rust-umbral.git", rev = "fd2e16f9304b9dab85c9a8947a61d962ff136131" }
+ferveo = { package = "ferveo-pre-release", features = ["bindings-python"], git = "https://github.com/nucypher/ferveo.git", rev = "c3b749732cc2d560240f7a1043c18d10138e30e9" }
 derive_more = { version = "0.99", default-features = false, features = ["from", "as_ref"] }
 
 [build-dependencies]
diff --git a/nucypher-core-python/README.md b/nucypher-core-python/README.md
index 90db8b68..1163f9c1 100644
--- a/nucypher-core-python/README.md
+++ b/nucypher-core-python/README.md
@@ -9,6 +9,13 @@ This repo contains the Python bindings for the [main Rust project][nucypher-core
 
 You will need to have `setuptools-rust` installed. Then, for development you can just do `pip install -e .` as usual.
 
+## Development
+
+Update `nucypher-core-python/stubtest-allowlist.txt` with:
+```bash
+cd umbral-pre-python
+python -m mypy.stubtest nucypher_core --generate-allowlist > stubtest-allowlist.txt
+```
 
 [pypi-image]: https://img.shields.io/pypi/v/nucypher-core
 [pypi-link]: https://pypi.org/project/nucypher-core/
diff --git a/nucypher-core-python/nucypher_core/__init__.pyi b/nucypher-core-python/nucypher_core/__init__.pyi
index 677d609f..96093475 100644
--- a/nucypher-core-python/nucypher_core/__init__.pyi
+++ b/nucypher-core-python/nucypher_core/__init__.pyi
@@ -12,7 +12,8 @@ from .umbral import (
 
 from .ferveo import (
     FerveoPublicKey,
-    Ciphertext
+    Ciphertext,
+    FerveoVariant
 )
 
 
@@ -431,7 +432,7 @@ class MetadataResponse:
 @final
 class ThresholdDecryptionRequest:
 
-    def __init__(self, ritual_id: int, variant: int, ciphertext: Ciphertext, conditions: Optional[Conditions],
+    def __init__(self, ritual_id: int, variant: FerveoVariant, ciphertext: Ciphertext, conditions: Optional[Conditions],
                  context: Optional[Context]):
         ...
 
@@ -441,7 +442,7 @@ class ThresholdDecryptionRequest:
 
     context: Optional[Context]
 
-    variant: int
+    variant: FerveoVariant
 
     ciphertext: Ciphertext
 
diff --git a/nucypher-core-python/nucypher_core/ferveo.pyi b/nucypher-core-python/nucypher_core/ferveo.pyi
index 9fc82342..7e45d878 100644
--- a/nucypher-core-python/nucypher_core/ferveo.pyi
+++ b/nucypher-core-python/nucypher_core/ferveo.pyi
@@ -1,5 +1,6 @@
 from typing import Sequence, final
 
+
 @final
 class Keypair:
     @staticmethod
@@ -24,6 +25,7 @@ class Keypair:
     def public_key(self) -> FerveoPublicKey:
         ...
 
+
 @final
 class FerveoPublicKey:
     @staticmethod
@@ -40,6 +42,7 @@ class FerveoPublicKey:
     def serialized_size() -> int:
         ...
 
+
 @final
 class Validator:
 
@@ -50,6 +53,7 @@ class Validator:
 
     public_key: FerveoPublicKey
 
+
 @final
 class Transcript:
     @staticmethod
@@ -59,6 +63,7 @@ class Transcript:
     def __bytes__(self) -> bytes:
         ...
 
+
 @final
 class DkgPublicKey:
     @staticmethod
@@ -72,6 +77,7 @@ class DkgPublicKey:
     def serialized_size() -> int:
         ...
 
+
 @final
 class ValidatorMessage:
 
@@ -85,6 +91,7 @@ class ValidatorMessage:
     validator: Validator
     transcript: Transcript
 
+
 @final
 class Dkg:
 
@@ -106,6 +113,7 @@ class Dkg:
     def aggregate_transcripts(self, messages: Sequence[ValidatorMessage]) -> AggregatedTranscript:
         ...
 
+
 @final
 class Ciphertext:
     @staticmethod
@@ -115,6 +123,7 @@ class Ciphertext:
     def __bytes__(self) -> bytes:
         ...
 
+
 @final
 class DecryptionShareSimple:
     @staticmethod
@@ -123,6 +132,8 @@ class DecryptionShareSimple:
 
     def __bytes__(self) -> bytes:
         ...
+
+
 @final
 class DecryptionSharePrecomputed:
     @staticmethod
@@ -132,6 +143,7 @@ class DecryptionSharePrecomputed:
     def __bytes__(self) -> bytes:
         ...
 
+
 @final
 class AggregatedTranscript:
 
@@ -166,6 +178,7 @@ class AggregatedTranscript:
     def __bytes__(self) -> bytes:
         ...
 
+
 @final
 class SharedSecret:
 
@@ -179,8 +192,11 @@ class SharedSecret:
 
 @final
 class FerveoVariant:
-    simple: str
-    precomputed: str
+    simple: FerveoVariant
+    precomputed: FerveoVariant
+
+    def __eq__(self, other: object) -> bool:
+        ...
 
 
 def encrypt(message: bytes, aad: bytes, dkg_public_key: DkgPublicKey) -> Ciphertext:
@@ -188,13 +204,13 @@ def encrypt(message: bytes, aad: bytes, dkg_public_key: DkgPublicKey) -> Ciphert
 
 
 def combine_decryption_shares_simple(
-        shares: Sequence[DecryptionShareSimple],
+        decryption_shares: Sequence[DecryptionShareSimple],
 ) -> bytes:
     ...
 
 
 def combine_decryption_shares_precomputed(
-        shares: Sequence[DecryptionSharePrecomputed],
+        decryption_shares: Sequence[DecryptionSharePrecomputed],
 ) -> SharedSecret:
     ...
 
diff --git a/nucypher-core-python/nucypher_core/umbral.pyi b/nucypher-core-python/nucypher_core/umbral.pyi
index 0733cb74..c83e56a4 100644
--- a/nucypher-core-python/nucypher_core/umbral.pyi
+++ b/nucypher-core-python/nucypher_core/umbral.pyi
@@ -1,4 +1,4 @@
-from typing import Optional, Tuple, List, final
+from typing import Optional, Tuple, List, final, Sequence
 
 
 @final
@@ -124,8 +124,8 @@ class KeyFrag:
     def verify(
             self,
             verifying_pk: PublicKey,
-            delegating_pk: Optional[PublicKey] = ...,
-            receiving_pk: Optional[PublicKey] = ...,
+            delegating_pk: Optional[PublicKey] = None,
+            receiving_pk: Optional[PublicKey] = None,
     ) -> VerifiedKeyFrag:
         ...
 
@@ -207,13 +207,13 @@ def reencrypt(capsule: Capsule, kfrag: VerifiedKeyFrag) -> VerifiedCapsuleFrag:
 
 @final
 class CurvePoint:
-    coordinates: Tuple[bytes, bytes]
+    coordinates: Optional[Tuple[bytes, bytes]]
 
 
 @final
 class Parameters:
 
-    def __init__(self, *args) -> None:
+    def __init__(self) -> None:
         ...
 
     u: CurvePoint
diff --git a/nucypher-core-python/src/lib.rs b/nucypher-core-python/src/lib.rs
index 42d4aaba..7ecda0d7 100644
--- a/nucypher-core-python/src/lib.rs
+++ b/nucypher-core-python/src/lib.rs
@@ -749,7 +749,7 @@ impl ThresholdDecryptionRequest {
     #[new]
     pub fn new(
         ritual_id: u32,
-        variant: &str,
+        variant: FerveoVariant,
         ciphertext: &Ciphertext,
         conditions: Option<&Conditions>,
         context: Option<&Context>,
@@ -762,7 +762,7 @@ impl ThresholdDecryptionRequest {
                     .map(|conditions| conditions.backend.clone())
                     .as_ref(),
                 context.map(|context| context.backend.clone()).as_ref(),
-                variant,
+                variant.into(),
             ),
         })
     }
diff --git a/nucypher-core-python/stubtest-allowlist.txt b/nucypher-core-python/stubtest-allowlist.txt
new file mode 100644
index 00000000..e7fbe133
--- /dev/null
+++ b/nucypher-core-python/stubtest-allowlist.txt
@@ -0,0 +1 @@
+nucypher_core.umbral.Parameters.__init__
diff --git a/nucypher-core-wasm/Cargo.toml b/nucypher-core-wasm/Cargo.toml
index 70de7317..efddd879 100644
--- a/nucypher-core-wasm/Cargo.toml
+++ b/nucypher-core-wasm/Cargo.toml
@@ -19,8 +19,8 @@ crate-type = ["cdylib", "rlib"]
 default = ["console_error_panic_hook"]
 
 [dependencies]
-umbral-pre = { version = "0.10.0", features = ["bindings-wasm"], git = "https://github.com/piotr-roslaniec/rust-umbral.git", ref = "4b28a85c494e4e2640abb131460da0680a74134d" }
-ferveo = { package = "ferveo-pre-release", features = ["bindings-wasm"], git = "https://github.com/nucypher/ferveo.git", ref = "fbb97be59d991a263233a0b876da982143b2cbf2" }
+umbral-pre = { version = "0.10.0", features = ["bindings-wasm"], git = "https://github.com/piotr-roslaniec/rust-umbral.git", rev = "fd2e16f9304b9dab85c9a8947a61d962ff136131" }
+ferveo = { package = "ferveo-pre-release", features = ["bindings-wasm"], git = "https://github.com/nucypher/ferveo.git", rev = "c3b749732cc2d560240f7a1043c18d10138e30e9" }
 nucypher-core = { path = "../nucypher-core" }
 wasm-bindgen = "0.2.86"
 js-sys = "0.3.63"
diff --git a/nucypher-core/Cargo.toml b/nucypher-core/Cargo.toml
index dd08e8cd..53a606cf 100644
--- a/nucypher-core/Cargo.toml
+++ b/nucypher-core/Cargo.toml
@@ -10,8 +10,8 @@ readme = "README.md"
 categories = ["cryptography", "no-std"]
 
 [dependencies]
-umbral-pre = { version = "0.10.0", features = ["serde"], git = "https://github.com/piotr-roslaniec/rust-umbral.git", ref = "4b28a85c494e4e2640abb131460da0680a74134d" }
-ferveo = { package = "ferveo-pre-release", git = "https://github.com/nucypher/ferveo.git", ref = "fbb97be59d991a263233a0b876da982143b2cbf2" }
+umbral-pre = { version = "0.10.0", features = ["serde"], git = "https://github.com/piotr-roslaniec/rust-umbral.git", rev = "fd2e16f9304b9dab85c9a8947a61d962ff136131" }
+ferveo = { package = "ferveo-pre-release", git = "https://github.com/nucypher/ferveo.git", rev = "c3b749732cc2d560240f7a1043c18d10138e30e9" }
 serde = { version = "1", default-features = false, features = ["derive"] }
 generic-array = { version = "0.14", features = ["zeroize"] }
 sha3 = "0.10"