diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 7264e42..3b2074a 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -15,6 +15,10 @@ jobs:
       run: python -m pip install --upgrade pip setuptools wheel
     - name: Install dependencies
       run: python -m pip install -r requirements.txt
+    - name: Install lint dependencies
+      run: python -m pip install --upgrade mypy
+    - name: Lint
+      run: python -m mypy -p linehaul
     - name: Install test dependencies
       run: python -m pip install pytest pretend hypothesis pyaml
     - name: Test
diff --git a/linehaul/events/parser.py b/linehaul/events/parser.py
index 9984fca..029cd1e 100644
--- a/linehaul/events/parser.py
+++ b/linehaul/events/parser.py
@@ -22,7 +22,7 @@
 import cattr
 
 from pyparsing import Literal as L, Word, Optional as OptionalItem
-from pyparsing import printables as _printables, restOfLine
+from pyparsing import printables as _printables, rest_of_line
 from pyparsing import ParseException
 
 from linehaul.ua import UserAgent, parser as user_agents
@@ -44,11 +44,11 @@ class UnparseableEvent(Exception):
     pass
 
 
-class NullValue:
+class _NullValue:
     pass
 
 
-NullValue = NullValue()
+NullValue = _NullValue()
 
 
 printables = "".join(set(_printables + " " + "\t") - {"|", "@"})
@@ -58,29 +58,26 @@ class NullValue:
 AT = L("@").suppress()
 
 NULL = L("(null)")
-NULL.setParseAction(lambda s, l, t: NullValue)
+NULL.set_parse_action(lambda s, l, t: NullValue)
 
-TIMESTAMP = Word(printables)
-TIMESTAMP = TIMESTAMP.setResultsName("timestamp")
-TIMESTAMP.setName("Timestamp")
+TIMESTAMP = Word(printables).set_name("Timestamp")
+TIMESTAMP = TIMESTAMP.set_results_name("timestamp")
 
-COUNTRY_CODE = Word(printables)
-COUNTRY_CODE = COUNTRY_CODE.setResultsName("country_code")
-COUNTRY_CODE.setName("Country Code")
+COUNTRY_CODE = Word(printables).set_name("Country Code")
+COUNTRY_CODE = COUNTRY_CODE.set_results_name("country_code")
 
-URL = Word(printables)
-URL = URL.setResultsName("url")
-URL.setName("URL")
+URL = Word(printables).set_name("URL")
+URL = URL.set_results_name("url")
 
 REQUEST = TIMESTAMP + PIPE + OptionalItem(COUNTRY_CODE) + PIPE + URL
 
 PROJECT_NAME = NULL | Word(printables)
-PROJECT_NAME = PROJECT_NAME.setResultsName("project_name")
-PROJECT_NAME.setName("Project Name")
+PROJECT_NAME = PROJECT_NAME.set_results_name("project_name")
+PROJECT_NAME.set_name("Project Name")
 
 VERSION = NULL | Word(printables)
-VERSION = VERSION.setResultsName("version")
-VERSION.setName("Version")
+VERSION = VERSION.set_results_name("version")
+VERSION.set_name("Version")
 
 PACKAGE_TYPE = NULL | (
     L("sdist")
@@ -92,34 +89,34 @@ class NullValue:
     | L("bdist_rpm")
     | L("bdist_wininst")
 )
-PACKAGE_TYPE = PACKAGE_TYPE.setResultsName("package_type")
-PACKAGE_TYPE.setName("Package Type")
+PACKAGE_TYPE = PACKAGE_TYPE.set_results_name("package_type")
+PACKAGE_TYPE.set_name("Package Type")
 
 PROJECT = PROJECT_NAME + PIPE + VERSION + PIPE + PACKAGE_TYPE
 
 TLS_PROTOCOL = NULL | Word(printables)
-TLS_PROTOCOL = TLS_PROTOCOL.setResultsName("tls_protocol")
-TLS_PROTOCOL.setName("TLS Protocol")
+TLS_PROTOCOL = TLS_PROTOCOL.set_results_name("tls_protocol")
+TLS_PROTOCOL.set_name("TLS Protocol")
 
 TLS_CIPHER = NULL | Word(printables)
-TLS_CIPHER = TLS_CIPHER.setResultsName("tls_cipher")
-TLS_CIPHER.setName("TLS Cipher")
+TLS_CIPHER = TLS_CIPHER.set_results_name("tls_cipher")
+TLS_CIPHER.set_name("TLS Cipher")
 
 TLS = TLS_PROTOCOL + PIPE + TLS_CIPHER
 
-USER_AGENT = restOfLine
-USER_AGENT = USER_AGENT.setResultsName("user_agent")
-USER_AGENT.setName("UserAgent")
+USER_AGENT = rest_of_line
+USER_AGENT = USER_AGENT.set_results_name("user_agent")
+USER_AGENT.set_name("UserAgent")
 
 V1_HEADER = OptionalItem(L("1").suppress() + AT)
 
 MESSAGE_v1 = V1_HEADER + REQUEST + PIPE + PROJECT + PIPE + USER_AGENT
-MESSAGE_v1.leaveWhitespace()
+MESSAGE_v1.leave_whitespace()
 
 V2_HEADER = L("2").suppress() + AT
 
 MESSAGE_v2 = V2_HEADER + REQUEST + PIPE + TLS + PIPE + PROJECT + PIPE + USER_AGENT
-MESSAGE_v2.leaveWhitespace()
+MESSAGE_v2.leave_whitespace()
 
 V3_HEADER = L("download")
 MESSAGE_v3 = (
@@ -204,7 +201,7 @@ def _value_or_none(value):
 
 def parse(message):
     try:
-        parsed = MESSAGE.parseString(message, parseAll=True)
+        parsed = MESSAGE.parse_string(message, parseAll=True)
     except ParseException as exc:
         raise UnparseableEvent("{!r} {}".format(message, exc)) from None
 
diff --git a/linehaul/py.typed b/linehaul/py.typed
new file mode 100644
index 0000000..e69de29
diff --git a/linehaul/ua/parser.py b/linehaul/ua/parser.py
index 66494c8..4a00d2c 100644
--- a/linehaul/ua/parser.py
+++ b/linehaul/ua/parser.py
@@ -333,7 +333,7 @@ def BrowserUserAgent():
 )
 
 
-def parse(user_agent):
+def parse(user_agent: str) -> UserAgent | None:
     try:
         return cattr.structure(_parser(user_agent), UserAgent)
     except UnableToParse:
diff --git a/pyproject.toml b/pyproject.toml
index 1fe725a..76e7a07 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -19,6 +19,7 @@ classifiers = [
   "Programming Language :: Python :: 3",
   "Programming Language :: Python :: 3.11",
   "Programming Language :: Python :: 3 :: Only",
+  "Typing :: Typed",
 ]
 
 dependencies = [
diff --git a/setup.cfg b/setup.cfg
index fa17e87..4e049d4 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,2 +1,5 @@
 [options]
 packages = find:
+
+[options.package_data]
+* = py.typed