diff --git a/rust2rpm/distgit.py b/rust2rpm/distgit.py
index 1a5be83..bd4de08 100644
--- a/rust2rpm/distgit.py
+++ b/rust2rpm/distgit.py
@@ -1,3 +1,4 @@
+from typing import Optional
 from urllib.parse import urljoin
 
 import requests
@@ -6,7 +7,7 @@ import requests
 DIST_GIT_API_URL = "https://src.fedoraproject.org/api/0/"
 
 
-def get_package_info(package):
+def get_package_info(package: str) -> Optional[dict]:
     """Download information about package from dist-git.
 
     Returns JSON with package metadata, or None if the package is
diff --git a/rust2rpm/generator.py b/rust2rpm/generator.py
index e0ca5ed..0363bb2 100644
--- a/rust2rpm/generator.py
+++ b/rust2rpm/generator.py
@@ -27,7 +27,7 @@ def spec_file_template(filename: str):
 
 
 def template_args_fedora(date: Optional[time.struct_time], packager: Optional[str], rpmautospec: bool) -> dict:
-    kwargs = dict()
+    kwargs: dict[str, str | bool] = dict()
 
     kwargs["include_build_requires"] = False
     kwargs["include_provides"] = False
@@ -50,7 +50,7 @@ def template_args_fedora(date: Optional[time.struct_time], packager: Optional[st
 
 
 def template_args_mageia(date: Optional[time.struct_time], packager: Optional[str]) -> dict:
-    kwargs = dict()
+    kwargs: dict[str, str | bool] = dict()
 
     kwargs["include_build_requires"] = True
     kwargs["include_provides"] = False
@@ -71,7 +71,7 @@ def template_args_mageia(date: Optional[time.struct_time], packager: Optional[st
 
 
 def template_args_opensuse(date: Optional[time.struct_time], packager: Optional[str]) -> dict:
-    kwargs = dict()
+    kwargs: dict[str, str | bool] = dict()
 
     kwargs["include_build_requires"] = True
     kwargs["include_provides"] = False
@@ -93,7 +93,7 @@ def template_args_opensuse(date: Optional[time.struct_time], packager: Optional[
 
 
 def template_args_plain(date: Optional[time.struct_time], packager: Optional[str]) -> dict:
-    kwargs = dict()
+    kwargs: dict[str, str | bool] = dict()
 
     kwargs["include_build_requires"] = True
     kwargs["include_provides"] = True
@@ -326,7 +326,7 @@ def spec_render_workspace(
     else:
         cargo_args = ""
 
-    license_strs = {package.license for package in metadata.packages}
+    license_strs = {package.license for package in metadata.packages if package.license}
     if len(license_strs) == 1:
         rpm_license_tag, rpm_license_comments = translate_license(target, list(license_strs)[0])
     else:
diff --git a/rust2rpm/licensing.py b/rust2rpm/licensing.py
index 20bc57d..f375387 100644
--- a/rust2rpm/licensing.py
+++ b/rust2rpm/licensing.py
@@ -1,13 +1,14 @@
 import os
 import csv
 import functools
+from typing import Optional
 
 from rust2rpm import log
 
 SPDX_TO_FEDORA_CSV = os.path.dirname(__file__) + "/spdx_to_fedora.csv"
 
 
-def translate_slashes(license):
+def translate_slashes(license: str) -> str:
     "Replace all slashes with OR, emit warning"
     split = [l.strip() for l in license.split("/")]
     if len(split) > 1:
@@ -16,7 +17,7 @@ def translate_slashes(license):
 
 
 @functools.lru_cache()
-def spdx_to_fedora_map():
+def spdx_to_fedora_map() -> dict[str, str]:
     with open(SPDX_TO_FEDORA_CSV, newline="") as f:
         reader = csv.DictReader(f)
         return {
@@ -31,7 +32,7 @@ def dump_sdpx_to_fedora_map(file):
         print(f"{k} → {v}", file=file)
 
 
-def translate_license_fedora(license):
+def translate_license_fedora(license: str) -> tuple[str, Optional[str]]:
     comments = []
     final = []
     for tag in license.split():
@@ -64,7 +65,7 @@ def translate_license_fedora(license):
     return (" ".join(final), "\n".join(comments) or None)
 
 
-def translate_license(target, license):
+def translate_license(target: str, license: str) -> tuple[str, Optional[str]]:
     license = translate_slashes(license)
     if target in {"mageia"}:
         return translate_license_fedora(license)
diff --git a/rust2rpm/log.py b/rust2rpm/log.py
index 0cdf2d2..bc14eb2 100644
--- a/rust2rpm/log.py
+++ b/rust2rpm/log.py
@@ -10,25 +10,25 @@ import textwrap
 from termcolor import colored
 
 
-def _eprint(message):
+def _eprint(message: str):
     print(message, file=sys.stderr)
 
 
-def _wrap(message, prefix):
+def _wrap(message: str, prefix: str):
     return textwrap.wrap(message, 80, initial_indent=f"{prefix} ", subsequent_indent=" " * (len(prefix) + 1))
 
 
-def success(message):
+def success(message: str):
     _eprint(colored("\n".join(_wrap(message, "•")), "green"))
 
 
-def info(message):
+def info(message: str):
     _eprint(colored("\n".join(_wrap(message, "•")), "grey"))
 
 
-def warn(message):
+def warn(message: str):
     _eprint(colored("\n".join(_wrap(message, "WARNING:")), "yellow"))
 
 
-def error(message):
+def error(message: str):
     _eprint(colored("\n".join(_wrap(message, "ERROR:")), "red", attrs=["dark"]))
diff --git a/rust2rpm/utils.py b/rust2rpm/utils.py
index 389501c..bc99dc7 100644
--- a/rust2rpm/utils.py
+++ b/rust2rpm/utils.py
@@ -1,6 +1,7 @@
 import contextlib
 import glob
 import os
+from pathlib import Path
 import re
 import sys
 import shlex
@@ -40,7 +41,7 @@ def exit_on_common_errors():
         sys.exit(str(e))
 
 
-def detect_editor():
+def detect_editor() -> str:
     terminal = os.getenv("TERM")
     terminal_is_dumb = not terminal or terminal == "dumb"
     editor = None
@@ -55,7 +56,7 @@ def detect_editor():
     return editor
 
 
-def detect_packager():
+def detect_packager() -> Optional[str]:
     # If we're forcing the fallback...
     if os.getenv("RUST2RPM_NO_DETECT_PACKAGER"):
         return None
@@ -77,7 +78,7 @@ def detect_packager():
     return None
 
 
-def guess_crate_name():
+def guess_crate_name() -> Optional[str]:
     """Guess crate name from directory name and/or spec file name
 
     If a spec file is present, we use the %crate variable. This is the best
@@ -143,7 +144,7 @@ def package_name_compat(name: str, version: str):
     return package_name_suffixed(name, suffix)
 
 
-def detect_rpmautospec(default_target, spec_file):
+def detect_rpmautospec(default_target: str, spec_file: Path):
     """Guess whether %autorelease+%autochangelog should be used
 
     Returns False if we're not on Fedora or if the spec file exists and
diff --git a/tox.ini b/tox.ini
index 29ba8c4..c121073 100644
--- a/tox.ini
+++ b/tox.ini
@@ -33,6 +33,8 @@ setenv =
 deps =
     mypy
     pytest
+    types-requests
+    types-tqdm
     -rrequirements.txt
 commands =
     mypy -p rust2rpm {posargs}