diff --git a/redwood/redwood/__init__.pyi b/redwood/redwood/__init__.pyi
index 90a0ede213..d4179e740a 100644
--- a/redwood/redwood/__init__.pyi
+++ b/redwood/redwood/__init__.pyi
@@ -3,7 +3,7 @@
 from pathlib import Path
 from typing import BinaryIO
 
-def generate_source_key_pair(passphrase: str, email: str) -> (str, str, str): ...
+def generate_source_key_pair(passphrase: str, email: str) -> tuple[str, str, str]: ...
 def encrypt_message(recipients: list[str], plaintext: str, destination: Path) -> None: ...
 def encrypt_stream(recipients: list[str], plaintext: BinaryIO, destination: Path) -> None: ...
 def decrypt(ciphertext: bytes, secret_key: str, passphrase: str) -> bytes: ...
diff --git a/securedrop/bin/run-mypy b/securedrop/bin/run-mypy
index a88dc335a6..25f9d8840c 100755
--- a/securedrop/bin/run-mypy
+++ b/securedrop/bin/run-mypy
@@ -7,8 +7,9 @@ REPOROOT=$(git rev-parse --show-toplevel)
 cd "${REPOROOT}"
 
 if [ "$(command -v mypy)" ]; then
-    source "securedrop/bin/dev-deps"
-    build_redwood
+    # Point mypy at the redwood package with type stub, see second option on
+    # <https://mypy.readthedocs.io/en/stable/stubs.html#creating-a-stub>.
+    export MYPYPATH="./redwood"
     mypy ./securedrop ./admin --namespace-packages --explicit-package-bases "$@"
 elif [ -d "/opt/venvs/securedrop-app-code/" ]; then
     # Inside the dev container, but no mypy