diff --git a/addon/globalPlugins/MathCAT/MathCAT.py b/addon/globalPlugins/MathCAT/MathCAT.py
index fa7daaa..93983bb 100644
--- a/addon/globalPlugins/MathCAT/MathCAT.py
+++ b/addon/globalPlugins/MathCAT/MathCAT.py
@@ -23,14 +23,17 @@
 import gui
 
 from . import libmathcat_py as libmathcat
-from typing import List, Dict
+from typing import Type
+from collections.abc import Generator, Callable
 from keyboardHandler import KeyboardInputGesture  # navigation key strokes
 from logHandler import log  # logging
 from os import path  # set rule dir path
 from scriptHandler import script  # copy MathML via ctrl-c
-from synthDriverHandler import getSynth  # speech engine param setting
+from synthDriverHandler import (
+	getSynth,
+	SynthDriver,
+)
 from ctypes import windll  # register clipboard formats
-from typing import Optional
 from speech import getCurrentLanguage
 from speech.types import SpeechSequence
 
@@ -45,10 +48,13 @@
 	CharacterModeCommand,
 	PhonemeCommand,
 	IndexCommand,
+	ProsodyCommand,
+	SpeechCommand,
+	SynthCommand,
 )
 
 from textUtils import WCHAR_ENCODING
-from ctypes import c_wchar, WinError
+from ctypes import c_wchar, WinError, Array
 from api import getClipData
 from synthDrivers import _espeak
 
@@ -56,7 +62,7 @@
 
 addonHandler.initTranslation()
 
-RE_MATHML_SPEECH = re.compile(
+RE_MATHML_SPEECH: re.Pattern = re.compile(
 	# Break.
 	r"<break time='(?P<break>\d+)ms'/> ?"
 	# Pronunciation of characters.
@@ -73,12 +79,12 @@
 	r"|(?P<content>[^<]+)",
 )
 
-PROSODY_COMMANDS = {
+PROSODY_COMMANDS: dict[str, ProsodyCommand] = {
 	"pitch": PitchCommand,
 	"volume": VolumeCommand,
 	"rate": RateCommand,
 }
-RE_MATH_LANG = re.compile(r"""<math .*(xml:)?lang=["']([^'"]+)["'].*>""")
+RE_MATH_LANG: re.Pattern = re.compile(r"""<math .*(xml:)?lang=["']([^'"]+)["'].*>""")
 
 # try to get around espeak bug where voice slows down (for other voices, just a waste of time)
 # we use a global that gets set at a time when the rate is probably good (SetMathML)
@@ -87,7 +93,7 @@
 
 def getLanguageToUse(mathMl: str = "") -> str:
 	"""Get the language specified in a math tag if the language pref is Auto, else the language preference."""
-	mathCATLanguageSetting = "Auto"
+	mathCATLanguageSetting: str = "Auto"
 	try:
 		# ignore regional differences if the MathCAT language setting doesn't have it.
 		mathCATLanguageSetting = libmathcat.GetPreference("Language")
@@ -98,8 +104,8 @@ def getLanguageToUse(mathMl: str = "") -> str:
 	if mathCATLanguageSetting != "Auto":
 		return mathCATLanguageSetting
 
-	languageMatch = RE_MATH_LANG.search(mathMl)
-	language = (
+	languageMatch: re.Match | None = RE_MATH_LANG.search(mathMl)
+	language: str = (
 		languageMatch.group(2) if languageMatch else getCurrentLanguage()
 	)  # seems to be current voice's language
 	language = language.lower().replace("_", "-")
@@ -110,7 +116,7 @@ def getLanguageToUse(mathMl: str = "") -> str:
 	return language
 
 
-def convertSSMLTextForNVDA(text: str) -> list:
+def convertSSMLTextForNVDA(text: str) -> list[str | SpeechCommand]:
 	"""Change the SSML in the text into NVDA's command structure.
 	The environment is examined to determine whether a language switch is needed"""
 	# MathCAT's default rate is 180 wpm.
@@ -119,31 +125,31 @@ def convertSSMLTextForNVDA(text: str) -> list:
 
 	# find MathCAT's language setting and store it away (could be "Auto")
 	# if MathCAT's setting doesn't match NVDA's language setting, change the language that is used
-	mathCATLanguageSetting = "en"  # set in case GetPreference fails
+	mathCATLanguageSetting: str = "en"  # set in case GetPreference fails
 	try:
 		mathCATLanguageSetting = libmathcat.GetPreference("Language")
 	except Exception as e:
 		log.exception(e)
-	language = getLanguageToUse()
-	nvdaLanguage = getCurrentLanguage().replace("_", "-")
+	language: str = getLanguageToUse()
+	nvdaLanguage: str = getCurrentLanguage().replace("_", "-")
 	# log.info(f"mathCATLanguageSetting={mathCATLanguageSetting}, lang={language}, NVDA={nvdaLanguage}")
 
 	_monkeyPatchESpeak()
 
-	synth = getSynth()
+	synth: SynthDriver = getSynth()
 	# I tried the engines on a 180 word excerpt. The speeds do not change linearly and differ a it between engines
 	# At "50" espeak finished in 46 sec, sapi in 75 sec, and one core in 70; at '100' one core was much slower than the others
-	wpm = 2 * getSynth()._get_rate()
-	breakMulti = 180.0 / wpm
-	supportedCommands = synth.supportedCommands
-	useBreak = BreakCommand in supportedCommands
-	usePitch = PitchCommand in supportedCommands
+	wpm: int = 2 * getSynth()._get_rate()
+	breakMulti: float = 180.0 / wpm
+	supportedCommands: set[Type["SynthCommand"]] = synth.supportedCommands
+	useBreak: bool = BreakCommand in supportedCommands
+	usePitch: bool = PitchCommand in supportedCommands
 	# use_rate = RateCommand in supported_commands
 	# use_volume = VolumeCommand in supported_commands
-	usePhoneme = PhonemeCommand in supportedCommands
+	usePhoneme: bool = PhonemeCommand in supportedCommands
 	# as of 7/23, oneCore voices do not implement the CharacterModeCommand despite it being in supported_commands
-	useCharacter = CharacterModeCommand in supportedCommands and synth.name != "oneCore"
-	out = []
+	useCharacter: bool = CharacterModeCommand in supportedCommands and synth.name != "oneCore"
+	out: list[str | SpeechCommand] = []
 	if mathCATLanguageSetting != language:
 		# log.info(f"Setting language to {language}")
 		try:
@@ -154,14 +160,14 @@ def convertSSMLTextForNVDA(text: str) -> list:
 	if language != nvdaLanguage:
 		out.append(LangChangeCommand(language))
 
-	resetProsody = []
+	resetProsody: list[Type["ProsodyCommand"]] = []
 	# log.info(f"\ntext: {text}")
 	for m in RE_MATHML_SPEECH.finditer(text):
 		if m.lastgroup == "break":
 			if useBreak:
 				out.append(BreakCommand(time=int(int(m.group("break")) * breakMulti)))
 		elif m.lastgroup == "char":
-			ch = m.group("char")
+			ch: str = m.group("char")
 			if useCharacter:
 				out.extend((CharacterModeCommand(True), ch, CharacterModeCommand(False)))
 			else:
@@ -173,13 +179,13 @@ def convertSSMLTextForNVDA(text: str) -> list:
 				out.append(PitchCommand(multiplier=int(m.group(m.lastgroup))))
 				resetProsody.append(PitchCommand)
 		elif m.lastgroup in PROSODY_COMMANDS:
-			command = PROSODY_COMMANDS[m.lastgroup]
+			command: Type["ProsodyCommand"] = PROSODY_COMMANDS[m.lastgroup]
 			if command in supportedCommands:
 				out.append(command(multiplier=int(m.group(m.lastgroup)) / 100.0))
 				resetProsody.append(command)
 		elif m.lastgroup == "prosodyReset":
 			# for command in resetProsody:    # only supported commands were added, so no need to check
-			command = resetProsody.pop()
+			command: Type["ProsodyCommand"] = resetProsody.pop()
 			out.append(command(multiplier=1))
 		elif m.lastgroup == "phonemeText":
 			if usePhoneme:
@@ -210,27 +216,31 @@ class MathCATInteraction(mathPres.MathInteractionNVDAObject):
 	# MathML is put on the clipboard using the two formats below (defined by MathML spec)
 	# We use both formats because some apps may only use one or the other
 	# Note: filed https://github.com/nvaccess/nvda/issues/13240 to make this usable outside of MathCAT
-	CF_MathML = windll.user32.RegisterClipboardFormatW("MathML")
-	CF_MathML_Presentation = windll.user32.RegisterClipboardFormatW(
+	CF_MathML: int = windll.user32.RegisterClipboardFormatW("MathML")
+	CF_MathML_Presentation: int = windll.user32.RegisterClipboardFormatW(
 		"MathML Presentation",
 	)
 	# log.info("2**** MathCAT registering data formats:
 	#   CF_MathML %x, CF_MathML_Presentation %x" % (CF_MathML, CF_MathML_Presentation))
 
-	def __init__(self, provider=None, mathMl: Optional[str] = None):
+	def __init__(
+		self,
+		provider: mathPres.MathPresentationProvider = None,
+		mathMl: str | None = None,
+	):
 		super(MathCATInteraction, self).__init__(provider=provider, mathMl=mathMl)
 		if mathMl is None:
 			self.initMathML = "<math></math>"
 		else:
 			self.initMathML = mathMl
 
-	def reportFocus(self):
+	def reportFocus(self) -> None:
 		super(MathCATInteraction, self).reportFocus()
 		# try to get around espeak bug where voice slows down
 		if _synthesizerRate and getSynth().name == "espeak":
 			getSynth()._set_rate(_synthesizerRate)
 		try:
-			text = libmathcat.DoNavigateCommand("ZoomIn")
+			text: str = libmathcat.DoNavigateCommand("ZoomIn")
 			speech.speak(convertSSMLTextForNVDA(text))
 		except Exception as e:
 			log.exception(e)
@@ -242,10 +252,13 @@ def reportFocus(self):
 				# log.info(f'reportFocus: reset to {_synthesizer_rate}')
 				getSynth()._set_rate(_synthesizerRate)
 
-	def getBrailleRegions(self, review: bool = False):
+	def getBrailleRegions(
+		self,
+		review: bool = False,
+	) -> Generator[braille.Region, None, None]:
 		# log.info("***MathCAT start getBrailleRegions")
 		yield braille.NVDAObjectRegion(self, appendText=" ")
-		region = braille.Region()
+		region: braille.Region = braille.Region()
 		region.focusToHardLeft = True
 		# libmathcat.SetBrailleWidth(braille.handler.displaySize)
 		try:
@@ -259,7 +272,10 @@ def getBrailleRegions(self, review: bool = False):
 		# log.info("***MathCAT end getBrailleRegions ***")
 		yield region
 
-	def getScript(self, gesture: KeyboardInputGesture):
+	def getScript(
+		self,
+		gesture: KeyboardInputGesture,
+	) -> Callable[KeyboardInputGesture, None] | None:
 		# Pass most keys to MathCAT. Pretty ugly.
 		if (
 			isinstance(gesture, KeyboardInputGesture)
@@ -292,13 +308,13 @@ def getScript(self, gesture: KeyboardInputGesture):
 		else:
 			return super().getScript(gesture)
 
-	def script_navigate(self, gesture: KeyboardInputGesture):
+	def script_navigate(self, gesture: KeyboardInputGesture) -> None:
 		try:
 			# try to get around espeak bug where voice slows down
 			if _synthesizerRate and getSynth().name == "espeak":
 				getSynth()._set_rate(_synthesizerRate)
 			if gesture is not None:  # == None when initial focus -- handled in reportFocus()
-				modNames = gesture.modifierNames
+				modNames: list[str] = gesture.modifierNames
 				text = libmathcat.DoNavigateKeyPress(
 					gesture.vkCode,
 					"shift" in modNames,
@@ -323,10 +339,10 @@ def script_navigate(self, gesture: KeyboardInputGesture):
 
 		try:
 			# update the braille to reflect the nav position (might be excess code, but it works)
-			navNode = libmathcat.GetNavigationMathMLId()
+			navNode: tuple[str, int] = libmathcat.GetNavigationMathMLId()
 			brailleChars = libmathcat.GetBraille(navNode[0])
 			# log.info(f'braille display = {config.conf["braille"]["display"]}, braille_chars: {braille_chars}')
-			region = braille.Region()
+			region: braille.Region = braille.Region()
 			region.rawText = brailleChars
 			region.focusToHardLeft = True
 			region.update()
@@ -339,7 +355,7 @@ def script_navigate(self, gesture: KeyboardInputGesture):
 			# Translators: this message directs users to look in the log file
 			speech.speakMessage(_("Error in brailling math: see NVDA error log for details"))
 
-	_startsWithMath = re.compile("\\s*?<math")
+	_startsWithMath: re.Pattern = re.compile("\\s*?<math")
 
 	@script(
 		# Translators: Message to be announced during Keyboard Help
@@ -347,11 +363,11 @@ def script_navigate(self, gesture: KeyboardInputGesture):
 		# Translators: Name of the section in "Input gestures" dialog.
 		category=_("Clipboard"),
 		gesture="kb:control+c",
-	)  # type: ignore
-	def script_rawdataToClip(self, gesture: KeyboardInputGesture):
+	)
+	def script_rawdataToClip(self, gesture: KeyboardInputGesture) -> None:
 		try:
-			copyAs = "mathml"  # value used even if "CopyAs" pref is invalid
-			textToCopy = ""
+			copyAs: str = "mathml"  # value used even if "CopyAs" pref is invalid
+			textToCopy: str = ""
 			try:
 				copyAs = libmathcat.GetPreference("CopyAs").lower()
 			except Exception as e:
@@ -365,7 +381,7 @@ def script_rawdataToClip(self, gesture: KeyboardInputGesture):
 				if copyAs == "asciimath":
 					copyAs = "ASCIIMath"  # speaks better in at least some voices
 			else:
-				mathml = libmathcat.GetNavigationMathML()[0]
+				mathml: str = libmathcat.GetNavigationMathML()[0]
 				if not re.match(self._startsWithMath, mathml):
 					mathml = "<math>\n" + mathml + "</math>"  # copy will fix up name spacing
 				elif self.initMathML != "":
@@ -373,7 +389,7 @@ def script_rawdataToClip(self, gesture: KeyboardInputGesture):
 				if copyAs == "speech":
 					# save the old MathML, set the navigation MathML as MathMl, get the speech, then reset the MathML
 					savedMathML: str = self.initMathML
-					savedTTS = libmathcat.GetPreference("TTS")
+					savedTTS: str = libmathcat.GetPreference("TTS")
 					if savedMathML == "":  # shouldn't happen
 						raise Exception("Internal error -- MathML not set for copy")
 					libmathcat.SetPreference("TTS", "None")
@@ -395,14 +411,14 @@ def script_rawdataToClip(self, gesture: KeyboardInputGesture):
 
 	# not a perfect match sequence, but should capture normal MathML
 	# not a perfect match sequence, but should capture normal MathML
-	_mathTagHasNameSpace = re.compile("<math .*?xmlns.+?>")
-	_hasAddedId = re.compile(" id='[^'].+' data-id-added='true'")
-	_hasDataAttr = re.compile(" data-[^=]+='[^']*'")
+	_mathTagHasNameSpace: re.Pattern = re.compile("<math .*?xmlns.+?>")
+	_hasAddedId: re.Pattern = re.compile(" id='[^'].+' data-id-added='true'")
+	_hasDataAttr: re.Pattern = re.compile(" data-[^=]+='[^']*'")
 
 	def _wrapMathMLForClipBoard(self, text: str) -> str:
 		# cleanup the MathML a little
 		text = re.sub(self._hasAddedId, "", text)
-		mathMLWithNS = re.sub(self._hasDataAttr, "", text)
+		mathMLWithNS: str = re.sub(self._hasDataAttr, "", text)
 		if not re.match(self._mathTagHasNameSpace, mathMLWithNS):
 			mathMLWithNS = mathMLWithNS.replace(
 				"math",
@@ -411,7 +427,12 @@ def _wrapMathMLForClipBoard(self, text: str) -> str:
 			)
 		return mathMLWithNS
 
-	def _copyToClipAsMathML(self, text: str, isMathML: bool, notify: Optional[bool] = False) -> bool:
+	def _copyToClipAsMathML(
+		self,
+		text: str,
+		isMathML: bool,
+		notify: bool | None = False,
+	) -> bool:
 		"""Copies the given text to the windows clipboard.
 		@returns: True if it succeeds, False otherwise.
 		@param text: the text which will be copied to the clipboard
@@ -428,7 +449,7 @@ def _copyToClipAsMathML(self, text: str, isMathML: bool, notify: Optional[bool]
 					self._setClipboardData(self.CF_MathML, '<?xml version="1.0"?>' + text)
 					self._setClipboardData(self.CF_MathML_Presentation, '<?xml version="1.0"?>' + text)
 				self._setClipboardData(winUser.CF_UNICODETEXT, text)
-			got = getClipData()
+			got: str = getClipData()
 		except OSError:
 			if notify:
 				ui.reportTextCopiedToClipboard()  # No argument reports a failure.
@@ -441,19 +462,19 @@ def _copyToClipAsMathML(self, text: str, isMathML: bool, notify: Optional[bool]
 			ui.reportTextCopiedToClipboard()  # No argument reports a failure.
 		return False
 
-	def _setClipboardData(self, format, data: str):
+	def _setClipboardData(self, format: int, data: str) -> None:
 		# Need to support MathML Presentation, so this copied from winUser.py and the first two lines are commented out
 		# For now only unicode is a supported format
 		# if format!=CF_UNICODETEXT:
 		#     raise ValueError("Unsupported format")
-		text = data
-		bufLen = len(text.encode(WCHAR_ENCODING, errors="surrogatepass")) + 2
+		text: str = data
+		bufLen: int = len(text.encode(WCHAR_ENCODING, errors="surrogatepass")) + 2
 		# Allocate global memory
-		h = winKernel.HGLOBAL.alloc(winKernel.GMEM_MOVEABLE, bufLen)
+		h: winKernel.HGLOBAL = winKernel.HGLOBAL.alloc(winKernel.GMEM_MOVEABLE, bufLen)
 		# Acquire a lock to the global memory receiving a local memory address
 		with h.lock() as addr:
 			# Write the text into the allocated memory
-			buf = (c_wchar * bufLen).from_address(addr)
+			buf: Array[c_wchar] = (c_wchar * bufLen).from_address(addr)
 			buf.value = text
 		# Set the clipboard data with the global memory
 		if not windll.user32.SetClipboardData(format, h):
@@ -468,7 +489,7 @@ def __init__(self):
 
 		try:
 			# IMPORTANT -- SetRulesDir must be the first call to libmathcat besides GetVersion()
-			rulesDir = path.join(path.dirname(path.abspath(__file__)), "Rules")
+			rulesDir: str = path.join(path.dirname(path.abspath(__file__)), "Rules")
 			log.info(f"MathCAT {libmathcat.GetVersion()} installed. Using rules dir: {rulesDir}")
 			libmathcat.SetRulesDir(rulesDir)
 			libmathcat.SetPreference("TTS", "SSML")
@@ -477,18 +498,21 @@ def __init__(self):
 			# Translators: this message directs users to look in the log file
 			speech.speakMessage(_("MathCAT initialization failed: see NVDA error log for details"))
 
-	def getSpeechForMathMl(self, mathml: str):
+	def getSpeechForMathMl(
+		self,
+		mathml: str,
+	) -> list[str | SpeechCommand]:
 		global _synthesizerRate
-		synth = getSynth()
+		synth: SynthDriver = getSynth()
 		synthConfig = config.conf["speech"][synth.name]
 		if synth.name == "espeak":
-			_synthesizerRate = synthConfig["rate"]
+			_synthesizerRate: int = synthConfig["rate"]
 			# log.info(f'_synthesizer_rate={_synthesizer_rate}, get_rate()={getSynth()._get_rate()}')
 			getSynth()._set_rate(_synthesizerRate)
 		# log.info(f'..............get_rate()={getSynth()._get_rate()}, name={synth.name}')
 		try:
 			# need to set Language before the MathML for DecimalSeparator canonicalization
-			language = getLanguageToUse(mathml)
+			language: str = getLanguageToUse(mathml)
 			# MathCAT should probably be extended to accept "extlang" tagging, but it uses lang-region tagging at the moment
 			libmathcat.SetPreference("Language", language)
 			libmathcat.SetMathML(mathml)
@@ -499,7 +523,7 @@ def getSpeechForMathMl(self, mathml: str):
 			speech.speakMessage(_("Illegal MathML found: see NVDA error log for details"))
 			libmathcat.SetMathML("<math></math>")  # set it to something
 		try:
-			supportedCommands = synth.supportedCommands
+			supportedCommands: set[Type["SynthCommand"]] = synth.supportedCommands
 			# Set preferences for capital letters
 			libmathcat.SetPreference(
 				"CapitalLetters_Beep",
@@ -532,14 +556,14 @@ def getSpeechForMathMl(self, mathml: str):
 				# log.info(f'getSpeechForMathMl: reset to {_synthesizer_rate}')
 				getSynth()._set_rate(_synthesizerRate)
 
-	def _addSounds(self):
+	def _addSounds(self) -> bool:
 		try:
 			return libmathcat.GetPreference("SpeechSound") != "None"
 		except Exception as e:
 			log.exception(f"MathCAT: An exception occurred in _add_sounds: {e}")
 			return False
 
-	def getBrailleForMathMl(self, mathml: str):
+	def getBrailleForMathMl(self, mathml: str) -> str:
 		# log.info("***MathCAT getBrailleForMathMl")
 		try:
 			libmathcat.SetMathML(mathml)
@@ -557,17 +581,17 @@ def getBrailleForMathMl(self, mathml: str):
 			speech.speakMessage(_("Error in brailling math: see NVDA error log for details"))
 			return ""
 
-	def interactWithMathMl(self, mathml: str):
+	def interactWithMathMl(self, mathml: str) -> None:
 		MathCATInteraction(provider=self, mathMl=mathml).setFocus()
 		MathCATInteraction(provider=self, mathMl=mathml).script_navigate(None)
 
 
-CACHED_SYNTH = None
+CACHED_SYNTH: SynthDriver | None = None
 
 
-def _monkeyPatchESpeak():
+def _monkeyPatchESpeak() -> None:
 	global CACHED_SYNTH
-	currentSynth = getSynth()
+	currentSynth: SynthDriver = getSynth()
 	if currentSynth.name != "espeak" or CACHED_SYNTH == currentSynth:
 		return  # already patched
 
@@ -575,11 +599,11 @@ def _monkeyPatchESpeak():
 	currentSynth.speak = patchedSpeak.__get__(currentSynth, type(currentSynth))
 
 
-def patchedSpeak(self, speechSequence: SpeechSequence):  # noqa: C901
+def patchedSpeak(self, speechSequence: SpeechSequence) -> None:  # noqa: C901
 	# log.info(f"\npatched_speak input: {speechSequence}")
-	textList: List[str] = []
+	textList: list[str] = []
 	langChanged = False
-	prosody: Dict[str, int] = {}
+	prosody: dict[str, int] = {}
 	# We output malformed XML, as we might close an outer tag after opening an inner one; e.g.
 	# <voice><prosody></voice></prosody>.
 	# However, eSpeak doesn't seem to mind.
@@ -624,7 +648,7 @@ def patchedSpeak(self, speechSequence: SpeechSequence):  # noqa: C901
 		elif isinstance(item, PhonemeCommand):
 			# We can't use str.translate because we want to reject unknown characters.
 			try:
-				phonemes = "".join([self.IPA_TO_ESPEAK[char] for char in item.ipa])
+				phonemes: str = "".join([self.IPA_TO_ESPEAK[char] for char in item.ipa])
 				# There needs to be a space after the phoneme command.
 				# Otherwise, eSpeak will announce a subsequent SSML tag instead of processing it.
 				textList.append("[[%s]] " % phonemes)
diff --git a/addon/globalPlugins/MathCAT/MathCATPreferences.py b/addon/globalPlugins/MathCAT/MathCATPreferences.py
index ddd314a..8f2ed1e 100644
--- a/addon/globalPlugins/MathCAT/MathCATPreferences.py
+++ b/addon/globalPlugins/MathCAT/MathCATPreferences.py
@@ -10,7 +10,7 @@
 import gettext
 import addonHandler
 from logHandler import log  # logging
-from typing import List, Dict, Union, Callable
+from collections.abc import Callable
 from .MathCAT import convertSSMLTextForNVDA
 from speech import speak
 from zipfile import ZipFile
@@ -20,11 +20,11 @@
 
 # two constants to scale "PauseFactor"
 # these work out so that a slider that goes [0,14] has value ~100 at 7 and ~1000 at 14
-PAUSE_FACTOR_SCALE = 9.5
-PAUSE_FACTOR_LOG_BASE = 1.4
+PAUSE_FACTOR_SCALE: float = 9.5
+PAUSE_FACTOR_LOG_BASE: float = 1.4
 
 # initialize the user preferences tuples
-userPreferences: Dict[str, Dict[str, Union[int, str, bool]]] = {}
+userPreferences: dict[str, dict[str, int | str | bool]] = {}
 # Speech_Language is derived from the folder structures
 Speech_DecimalSeparator = ("Auto", ".", ",", "Custom")
 Speech_Impairment = ("LearningDisability", "Blindness", "LowVision")
@@ -47,7 +47,7 @@ def __init__(self, parent):
 		MathCATgui.MathCATPreferencesDialog.__init__(self, parent)
 
 		# load the logo into the dialog
-		fullPathToLogo = os.path.join(os.path.dirname(os.path.abspath(__file__)), "logo.png")
+		fullPathToLogo: str = os.path.join(os.path.dirname(os.path.abspath(__file__)), "logo.png")
 		if os.path.exists(fullPathToLogo):
 			self._bitmapLogo.SetBitmap(wx.Bitmap(fullPathToLogo))
 
@@ -78,17 +78,17 @@ def __init__(self, parent):
 		UserInterface.setUIValues(self)
 
 	@staticmethod
-	def pathToLanguagesFolder():
+	def pathToLanguagesFolder() -> str:
 		# the user preferences file is stored at: MathCAT\Rules\Languages
 		return os.path.join(os.path.dirname(os.path.abspath(__file__)), "Rules", "Languages")
 
 	@staticmethod
-	def pathToBrailleFolder():
+	def pathToBrailleFolder() -> str:
 		# the user preferences file is stored at: MathCAT\Rules\Languages
 		return os.path.join(os.path.dirname(os.path.abspath(__file__)), "Rules", "Braille")
 
 	@staticmethod
-	def languagesDict() -> Dict[str, str]:
+	def languagesDict() -> dict[str, str]:
 		languages = {
 			"aa": "Afar",
 			"ab": "Аҧсуа",
@@ -268,10 +268,12 @@ def languagesDict() -> Dict[str, str]:
 	def getRulesFiles(
 		self,
 		pathToDir: str,
-		processSubDirs: Callable[[str, str], List[str]] | None,
-	) -> List[str]:
-		language = os.path.basename(pathToDir)
-		ruleFiles = [os.path.basename(file) for file in glob.glob(os.path.join(pathToDir, "*_Rules.yaml"))]
+		processSubDirs: Callable[[str, str], list[str]] | None,
+	) -> list[str]:
+		language: str = os.path.basename(pathToDir)
+		ruleFiles: list[str] = [
+			os.path.basename(file) for file in glob.glob(os.path.join(pathToDir, "*_Rules.yaml"))
+		]
 		for dir in os.listdir(pathToDir):
 			if os.path.isdir(os.path.join(pathToDir, dir)):
 				if processSubDirs:
@@ -280,7 +282,7 @@ def getRulesFiles(
 		if len(ruleFiles) == 0:
 			# look in the .zip file for the style files, including regional subdirs -- it might not have been unzipped
 			try:
-				zip_file = ZipFile(f"{pathToDir}\\{language}.zip", "r")
+				zip_file: ZipFile = ZipFile(f"{pathToDir}\\{language}.zip", "r")
 				for file in zip_file.namelist():
 					if file.endswith("_Rules.yaml"):
 						ruleFiles.append(file)
@@ -291,15 +293,15 @@ def getRulesFiles(
 
 		return ruleFiles
 
-	def getLanguages(self):
-		def addRegionalLanguages(subDir: str, language: str) -> List[str]:
+	def getLanguages(self) -> None:
+		def addRegionalLanguages(subDir: str, language: str) -> list[str]:
 			# the language variants are in folders named using ISO 3166-1 alpha-2
 			# codes https://en.wikipedia.org/wiki/ISO_3166-2
 			# check if there are language variants in the language folder
 			if subDir != "SharedRules":
-				languagesDict = UserInterface.languagesDict()
+				languagesDict: dict[str, str] = UserInterface.languagesDict()
 				# add to the listbox the text for this language variant together with the code
-				regionalCode = language + "-" + subDir.upper()
+				regionalCode: str = language + "-" + subDir.upper()
 				if languagesDict.get(regionalCode, "missing") != "missing":
 					self._choiceLanguage.Append(f"{languagesDict[regionalCode]} ({language}-{subDir})")
 				elif languagesDict.get(language, "missing") != "missing":
@@ -310,7 +312,7 @@ def addRegionalLanguages(subDir: str, language: str) -> List[str]:
 			return []
 
 		# initialise the language list
-		languagesDict = UserInterface.languagesDict()
+		languagesDict: dict[str, str] = UserInterface.languagesDict()
 		# clear the language names in the dialog
 		self._choiceLanguage.Clear()
 		# Translators: menu item -- use the language of the voice chosen in the NVDA speech settings dialog
@@ -319,9 +321,9 @@ def addRegionalLanguages(subDir: str, language: str) -> List[str]:
 		# populate the available language names in the dialog
 		# the implemented languages are in folders named using the relevant ISO 639-1
 		#   code https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes
-		languageDir = UserInterface.pathToLanguagesFolder()
+		languageDir: str = UserInterface.pathToLanguagesFolder()
 		for language in os.listdir(languageDir):
-			pathToLanguageDir = os.path.join(UserInterface.pathToLanguagesFolder(), language)
+			pathToLanguageDir: str = os.path.join(UserInterface.pathToLanguagesFolder(), language)
 			if os.path.isdir(pathToLanguageDir):
 				# only add this language if there is a xxx_Rules.yaml file
 				if len(self.getRulesFiles(pathToLanguageDir, addRegionalLanguages)) > 0:
@@ -331,10 +333,10 @@ def addRegionalLanguages(subDir: str, language: str) -> List[str]:
 					else:
 						self._choiceLanguage.Append(language + " (" + language + ")")
 
-	def getLanguageCode(self):
-		lang_selection = self._choiceLanguage.GetStringSelection()
-		lang_code = lang_selection[lang_selection.find("(") + 1 : lang_selection.find(")")]
-		return lang_code
+	def getLanguageCode(self) -> str:
+		langSelection: str = self._choiceLanguage.GetStringSelection()
+		langCode: str = langSelection[langSelection.find("(") + 1 : langSelection.find(")")]
+		return langCode
 
 	def getSpeechStyles(self, thisSpeechStyle: str):
 		"""Get all the speech styles for the current language.
@@ -346,10 +348,12 @@ def getSpeechStyleFromDirectory(dir: str, lang: str) -> list[str]:
 			The 'lang', if it has a region dialect, is of the form 'en\uk'
 			The returned list is sorted alphabetically"""
 			# start with the regional dialect, then add on any (unique) styles in the main dir
-			mainLang = lang.split("\\")[0]  # does the right thing even if there is no regional directory
-			allStyleFiles = []
+			mainLang: str = lang.split("\\")[0]  # does the right thing even if there is no regional directory
+			allStyleFiles: list[str] = []
 			if lang.find("\\") >= 0:
-				allStyleFiles = [os.path.basename(name) for name in glob.glob(dir + lang + "\\*_Rules.yaml")]
+				allStyleFiles: list[str] = [
+					os.path.basename(name) for name in glob.glob(dir + lang + "\\*_Rules.yaml")
+				]
 			allStyleFiles.extend(
 				[os.path.basename(name) for name in glob.glob(dir + mainLang + "\\*_Rules.yaml")],
 			)
@@ -357,8 +361,8 @@ def getSpeechStyleFromDirectory(dir: str, lang: str) -> list[str]:
 			if len(allStyleFiles) == 0:
 				# look in the .zip file for the style files -- this will have regional variants, but also have that dir
 				try:
-					zipFile = dir + mainLang + "\\" + mainLang + ".zip"
-					zipFile = ZipFile(zipFile, "r")  # file might not exist
+					zipFilePath: str = dir + mainLang + "\\" + mainLang + ".zip"
+					zipFile: ZipFile = ZipFile(zipFilePath, "r")  # file might not exist
 					allStyleFiles = [
 						name.split("/")[-1] for name in zipFile.namelist() if name.endswith("_Rules.yaml")
 					]
@@ -370,7 +374,7 @@ def getSpeechStyleFromDirectory(dir: str, lang: str) -> list[str]:
 		# clear the SpeechStyle choices
 		self._choiceSpeechStyle.Clear()
 		# get the currently selected language code
-		languageCode = UserInterface.getLanguageCode(self)
+		languageCode: str = UserInterface.getLanguageCode(self)
 
 		if languageCode == "Auto":
 			# list the speech styles for the current voice rather than have none listed
@@ -402,28 +406,28 @@ def getSpeechStyleFromDirectory(dir: str, lang: str) -> list[str]:
 			# that didn't work, choose the first in the list
 			self._choiceSpeechStyle.SetSelection(0)
 
-	def getBrailleCodes(self):
+	def getBrailleCodes(self) -> None:
 		# initialise the braille code list
 		self._choiceBrailleMathCode.Clear()
 		# populate the available braille codes in the dialog
 		# the dir names are used, not the rule file names because the dir names have to be unique
-		pathToBrailleFolder = UserInterface.pathToBrailleFolder()
+		pathToBrailleFolder: str = UserInterface.pathToBrailleFolder()
 		for brailleCode in os.listdir(pathToBrailleFolder):
-			pathToBrailleCode = os.path.join(pathToBrailleFolder, brailleCode)
+			pathToBrailleCode: str = os.path.join(pathToBrailleFolder, brailleCode)
 			if os.path.isdir(pathToBrailleCode):
 				if len(self.getRulesFiles(pathToBrailleCode, None)) > 0:
 					self._choiceBrailleMathCode.Append(brailleCode)
 
-	def setUIValues(self):
+	def setUIValues(self) -> None:
 		# set the UI elements to the ones read from the preference file(s)
 		try:
 			self._choiceImpairment.SetSelection(
 				Speech_Impairment.index(userPreferences["Speech"]["Impairment"]),
 			)
 			try:
-				langPref = userPreferences["Speech"]["Language"]
+				langPref: str = userPreferences["Speech"]["Language"]
 				self._choiceLanguage.SetSelection(0)
-				i = 1  # no need to test i == 0
+				i: int = 1  # no need to test i == 0
 				while i < self._choiceLanguage.GetCount():
 					if f"({langPref})" in self._choiceLanguage.GetString(i):
 						self._choiceLanguage.SetSelection(i)
@@ -489,7 +493,7 @@ def setUIValues(self):
 				Braille_BrailleNavHighlight.index(userPreferences["Braille"]["BrailleNavHighlight"]),
 			)
 			try:
-				braillePref = userPreferences["Braille"]["BrailleCode"]
+				braillePref: str = userPreferences["Braille"]["BrailleCode"]
 				i = 0
 				while braillePref != self._choiceBrailleMathCode.GetString(i):
 					i = i + 1
@@ -507,7 +511,7 @@ def setUIValues(self):
 		except KeyError as err:
 			print("Key not found", err)
 
-	def getUIValues(self):
+	def getUIValues(self) -> None:
 		global userPreferences
 		# read the values from the UI and update the user preferences dictionary
 		userPreferences["Speech"]["Impairment"] = Speech_Impairment[self._choiceImpairment.GetSelection()]
@@ -518,8 +522,8 @@ def getUIValues(self):
 		userPreferences["Speech"]["SpeechStyle"] = self._choiceSpeechStyle.GetStringSelection()
 		userPreferences["Speech"]["Verbosity"] = Speech_Verbosity[self._choiceSpeechAmount.GetSelection()]
 		userPreferences["Speech"]["MathRate"] = self._sliderRelativeSpeed.GetValue()
-		pfSlider = self._sliderPauseFactor.GetValue()
-		pauseFactor = (
+		pfSlider: int = self._sliderPauseFactor.GetValue()
+		pauseFactor: int = (
 			0 if pfSlider == 0 else round(PAUSE_FACTOR_SCALE * math.pow(PAUSE_FACTOR_LOG_BASE, pfSlider))
 		)  # avoid log(0)
 		userPreferences["Speech"]["PauseFactor"] = pauseFactor
@@ -551,21 +555,21 @@ def getUIValues(self):
 		userPreferences["NVDAAddOn"]["LastCategory"] = self._listBoxPreferencesTopic.GetSelection()
 
 	@staticmethod
-	def pathToDefaultPreferences():
+	def pathToDefaultPreferences() -> str:
 		return os.path.join(os.path.dirname(os.path.abspath(__file__)), "Rules", "prefs.yaml")
 
 	@staticmethod
-	def pathToUserPreferencesFolder():
+	def pathToUserPreferencesFolder() -> str:
 		# the user preferences file is stored at: C:\Users\<user-name>AppData\Roaming\MathCAT\prefs.yaml
 		return os.path.join(os.path.expandvars("%APPDATA%"), "MathCAT")
 
 	@staticmethod
-	def pathToUserPreferences():
+	def pathToUserPreferences() -> str:
 		# the user preferences file is stored at: C:\Users\<user-name>AppData\Roaming\MathCAT\prefs.yaml
 		return os.path.join(UserInterface.pathToUserPreferencesFolder(), "prefs.yaml")
 
 	@staticmethod
-	def loadDefaultPreferences():
+	def loadDefaultPreferences() -> None:
 		global userPreferences
 		# load default preferences into the user preferences data structure (overwrites existing)
 		if os.path.exists(UserInterface.pathToDefaultPreferences()):
@@ -576,7 +580,7 @@ def loadDefaultPreferences():
 				userPreferences = yaml.load(f, Loader=yaml.FullLoader)
 
 	@staticmethod
-	def loadUserPreferences():
+	def loadUserPreferences() -> None:
 		global userPreferences
 		# merge user file values into the user preferences data structure
 		if os.path.exists(UserInterface.pathToUserPreferences()):
@@ -585,7 +589,12 @@ def loadUserPreferences():
 				userPreferences.update(yaml.load(f, Loader=yaml.FullLoader))
 
 	@staticmethod
-	def validate(key1: str, key2: str, validValues: List[Union[str, bool]], defaultValue: Union[str, bool]):
+	def validate(
+		key1: str,
+		key2: str,
+		validValues: list[str | bool],
+		defaultValue: str | bool,
+	) -> None:
 		global userPreferences
 		try:
 			if validValues == []:
@@ -606,7 +615,12 @@ def validate(key1: str, key2: str, validValues: List[Union[str, bool]], defaultV
 			userPreferences[key1][key2] = defaultValue
 
 	@staticmethod
-	def validateInt(key1: str, key2: str, validValues: List[int], defaultValue: int):
+	def validateInt(
+		key1: str,
+		key2: str,
+		validValues: list[int],
+		defaultValue: int,
+	) -> None:
 		global userPreferences
 		try:
 			# any value between lower and upper bounds is valid
@@ -678,7 +692,7 @@ def validateUserPreferences():
 		UserInterface.validate("Braille", "BrailleCode", [], "Nemeth")
 
 	@staticmethod
-	def writeUserPreferences():
+	def writeUserPreferences() -> None:
 		# Language is special because it is set elsewhere by SetPreference which overrides the user_prefs -- so set it here
 		from . import libmathcat_py as libmathcat
 
@@ -695,23 +709,23 @@ def writeUserPreferences():
 			# write values to the user preferences file, NOT the default
 			yaml.dump(userPreferences, stream=f, allow_unicode=True)
 
-	def onRelativeSpeedChanged(self, event):
-		rate = self._sliderRelativeSpeed.GetValue()
+	def onRelativeSpeedChanged(self, event: wx.ScrollEvent) -> None:
+		rate: int = self._sliderRelativeSpeed.GetValue()
 		# Translators: this is a test string that is spoken. Only translate "the square root of x squared plus y squared"
-		text = _("<prosody rate='XXX%'>the square root of x squared plus y squared</prosody>").replace(
+		text: str = _("<prosody rate='XXX%'>the square root of x squared plus y squared</prosody>").replace(
 			"XXX",
 			str(rate),
 			1,
 		)
 		speak(convertSSMLTextForNVDA(text))
 
-	def onPauseFactorChanged(self, event):
-		rate = self._sliderRelativeSpeed.GetValue()
+	def onPauseFactorChanged(self, event: wx.ScrollEvent) -> None:
+		rate: int = self._sliderRelativeSpeed.GetValue()
 		pfSlider = self._sliderPauseFactor.GetValue()
 		pauseFactor = (
 			0 if pfSlider == 0 else round(PAUSE_FACTOR_SCALE * math.pow(PAUSE_FACTOR_LOG_BASE, pfSlider))
 		)
-		text = _(
+		text: str = _(
 			# Translators: this is a test string that is spoken. Only translate "the fraction with numerator"
 			# and other parts NOT inside '<.../>',
 			"<prosody rate='{rate}%'>the fraction with numerator <break time='{pause_factor_300}ms'/>\
@@ -732,37 +746,37 @@ def onPauseFactorChanged(self, event):
 		)
 		speak(convertSSMLTextForNVDA(text))
 
-	def onClickOK(self, event):
+	def onClickOK(self, event: wx.CommandEvent) -> None:
 		UserInterface.getUIValues(self)
 		UserInterface.writeUserPreferences()
 		self.Destroy()
 
-	def onClickCancel(self, event):
+	def onClickCancel(self, event: wx.CommandEvent) -> None:
 		self.Destroy()
 
-	def onClickApply(self, event):
+	def onClickApply(self, event: wx.CommandEvent) -> None:
 		UserInterface.getUIValues(self)
 		UserInterface.writeUserPreferences()
 
-	def onClickReset(self, event):
+	def onClickReset(self, event: wx.CommandEvent) -> None:
 		UserInterface.loadDefaultPreferences()
 		UserInterface.validateUserPreferences()
 		UserInterface.setUIValues(self)
 
-	def onClickHelp(self, event):
+	def onClickHelp(self, event: wx.CommandEvent) -> None:
 		webbrowser.open("https://nsoiffer.github.io/MathCAT/users.html")
 
-	def onListBoxCategories(self, event):
+	def onListBoxCategories(self, event: wx.CommandEvent) -> None:
 		# the category changed, now show the appropriate dialogue page
 		self._simplebookPanelsCategories.SetSelection(self._listBoxPreferencesTopic.GetSelection())
 
-	def onLanguage(self, event):
+	def onLanguage(self, event: wx.CommandEvent) -> None:
 		# the language changed, get the SpeechStyles for the new language
 		UserInterface.getSpeechStyles(self, self._choiceSpeechStyle.GetStringSelection())
 
-	def mathCATPreferencesDialogOnCharHook(self, event: wx.KeyEvent):
+	def mathCATPreferencesDialogOnCharHook(self, event: wx.KeyEvent) -> None:
 		# designed choice is that Enter is the same as clicking OK, and Escape is the same as clicking Cancel
-		keyCode = event.GetKeyCode()
+		keyCode: int = event.GetKeyCode()
 		if keyCode == wx.WXK_ESCAPE:
 			UserInterface.onClickCancel(self, event)
 			return
@@ -771,7 +785,7 @@ def mathCATPreferencesDialogOnCharHook(self, event: wx.KeyEvent):
 		if keyCode == wx.WXK_TAB:
 			if event.GetModifiers() == wx.MOD_CONTROL:
 				# cycle the category forward
-				newCategory = self._listBoxPreferencesTopic.GetSelection() + 1
+				newCategory: int = self._listBoxPreferencesTopic.GetSelection() + 1
 				if newCategory == 3:
 					newCategory = 0
 				self._listBoxPreferencesTopic.SetSelection(newCategory)
@@ -783,7 +797,7 @@ def mathCATPreferencesDialogOnCharHook(self, event: wx.KeyEvent):
 				return
 			if event.GetModifiers() == wx.MOD_CONTROL | wx.MOD_SHIFT:
 				# cycle the category back
-				newCategory = self._listBoxPreferencesTopic.GetSelection() - 1
+				newCategory: int = self._listBoxPreferencesTopic.GetSelection() - 1
 				if newCategory == -1:
 					newCategory = 2
 				self._listBoxPreferencesTopic.SetSelection(newCategory)
diff --git a/addon/globalPlugins/MathCAT/MathCATgui.py b/addon/globalPlugins/MathCAT/MathCATgui.py
index de214e5..e0bacf3 100644
--- a/addon/globalPlugins/MathCAT/MathCATgui.py
+++ b/addon/globalPlugins/MathCAT/MathCATgui.py
@@ -27,20 +27,20 @@ def __init__(self, parent):
 
 		self.SetSizeHints(wx.DefaultSize, wx.DefaultSize)
 
-		gbSizerMathCATPreferences = wx.GridBagSizer(0, 0)
+		gbSizerMathCATPreferences: wx.GridBagSizer = wx.GridBagSizer(0, 0)
 		gbSizerMathCATPreferences.SetFlexibleDirection(wx.BOTH)
 		gbSizerMathCATPreferences.SetNonFlexibleGrowMode(wx.FLEX_GROWMODE_SPECIFIED)
 
-		self._panelCategories = wx.Panel(
+		self._panelCategories: wx.Panel = wx.Panel(
 			self,
 			wx.ID_ANY,
 			wx.DefaultPosition,
 			wx.DefaultSize,
 			wx.TAB_TRAVERSAL,
 		)
-		bSizerCategories = wx.BoxSizer(wx.VERTICAL)
+		bSizerCategories: wx.BoxSizer = wx.BoxSizer(wx.VERTICAL)
 
-		self._staticTextCategories = wx.StaticText(
+		self._staticTextCategories: wx.StaticText = wx.StaticText(
 			self._panelCategories,
 			wx.ID_ANY,
 			# Translators: A heading that labels three navigation pane tab names in the MathCAT dialog
@@ -53,7 +53,7 @@ def __init__(self, parent):
 
 		bSizerCategories.Add(self._staticTextCategories, 0, wx.ALL, 5)
 
-		listBoxPreferencesTopicChoices = [
+		listBoxPreferencesTopicChoices: list[str] = [
 			# Translators: these are navigation pane headings for the MathCAT preferences dialog under the title "Categories"
 			_("Speech"),
 			# Translators: these are navigation pane headings for the MathCAT preferences dialog under the title "Categories"
@@ -61,7 +61,7 @@ def __init__(self, parent):
 			# Translators: these are navigation pane headings for the MathCAT preferences dialog under the title "Categories"
 			_("Braille"),
 		]
-		self._listBoxPreferencesTopic = wx.ListBox(
+		self._listBoxPreferencesTopic: wx.ListBox = wx.ListBox(
 			self._panelCategories,
 			wx.ID_ANY,
 			wx.Point(-1, -1),
@@ -73,7 +73,7 @@ def __init__(self, parent):
 
 		bSizerCategories.Add((0, 0), 1, wx.EXPAND, 5)
 
-		self._bitmapLogo = wx.StaticBitmap(
+		self._bitmapLogo: wx.StaticBitmap = wx.StaticBitmap(
 			self._panelCategories,
 			wx.ID_ANY,
 			wx.NullBitmap,
@@ -94,25 +94,25 @@ def __init__(self, parent):
 			5,
 		)
 
-		self._simplebookPanelsCategories = wx.Simplebook(
+		self._simplebookPanelsCategories: wx.Simplebook = wx.Simplebook(
 			self,
 			wx.ID_ANY,
 			wx.DefaultPosition,
 			wx.DefaultSize,
 			0,
 		)
-		self._panelSpeech = wx.Panel(
+		self._panelSpeech: wx.Panel = wx.Panel(
 			self._simplebookPanelsCategories,
 			wx.ID_ANY,
 			wx.DefaultPosition,
 			wx.DefaultSize,
 			wx.BORDER_SIMPLE | wx.TAB_TRAVERSAL,
 		)
-		bSizerSpeech = wx.BoxSizer(wx.VERTICAL)
+		bSizerSpeech: wx.BoxSizer = wx.BoxSizer(wx.VERTICAL)
 
-		bSizerImpairment = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerImpairment: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticTextImpairment = wx.StaticText(
+		self._staticTextImpairment: wx.StaticText = wx.StaticText(
 			self._panelSpeech,
 			wx.ID_ANY,
 			# Translators: this is the text label for whom to target the speech for (options are below)
@@ -125,7 +125,7 @@ def __init__(self, parent):
 
 		bSizerImpairment.Add(self._staticTextImpairment, 0, wx.ALL, 5)
 
-		impairmentChoices = [
+		impairmentChoices: list[str] = [
 			# Translators: these are the categories of impairments that MathCAT supports
 			# Translators: Learning disabilities includes dyslexia and ADHD
 			_("Learning disabilities"),
@@ -134,7 +134,7 @@ def __init__(self, parent):
 			# Translators: target people who have low vision
 			_("Low vision"),
 		]
-		self._choiceImpairment = wx.Choice(
+		self._choiceImpairment: wx.Choice = wx.Choice(
 			self._panelSpeech,
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -147,9 +147,9 @@ def __init__(self, parent):
 
 		bSizerSpeech.Add(bSizerImpairment, 1, wx.EXPAND, 5)
 
-		bSizerLanguage = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerLanguage: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticTextLanguage = wx.StaticText(
+		self._staticTextLanguage: wx.StaticText = wx.StaticText(
 			self._panelSpeech,
 			wx.ID_ANY,
 			# Translators: label for pull down allowing users to choose the speech language for math
@@ -162,8 +162,8 @@ def __init__(self, parent):
 
 		bSizerLanguage.Add(self._staticTextLanguage, 0, wx.ALL, 5)
 
-		languageChoices = ["xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"]
-		self._choiceLanguage = wx.Choice(
+		languageChoices: list[str] = ["xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"]
+		self._choiceLanguage: wx.Choice = wx.Choice(
 			self._panelSpeech,
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -176,9 +176,9 @@ def __init__(self, parent):
 
 		bSizerSpeech.Add(bSizerLanguage, 1, wx.EXPAND, 5)
 
-		bSizerDecimalSeparator = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerDecimalSeparator: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticTextDecimalSeparator = wx.StaticText(
+		self._staticTextDecimalSeparator: wx.StaticText = wx.StaticText(
 			self._panelSpeech,
 			wx.ID_ANY,
 			# Translators: label for pull down to specify what character to use in numbers as the decimal separator
@@ -192,7 +192,7 @@ def __init__(self, parent):
 		bSizerDecimalSeparator.Add(self._staticTextDecimalSeparator, 0, wx.ALL, 5)
 
 		# Translators: options for decimal separator.
-		decimalSeparatorChoices = [
+		decimalSeparatorChoices: list[str] = [
 			# Translators: options for decimal separator -- "Auto" = automatically pick the choice based on the language
 			_("Auto"),
 			# options for decimal separator -- use "."  (and use ", " for block separators)
@@ -203,7 +203,7 @@ def __init__(self, parent):
 			#   Currently there is no UI for how it is done yet, but eventually there will be a dialog that pops up to set it
 			_("Custom"),
 		]
-		self._choiceDecimalSeparator = wx.Choice(
+		self._choiceDecimalSeparator: wx.Choice = wx.Choice(
 			self._panelSpeech,
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -216,9 +216,9 @@ def __init__(self, parent):
 
 		bSizerSpeech.Add(bSizerDecimalSeparator, 1, wx.EXPAND, 5)
 
-		bSizerSpeechStyle = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerSpeechStyle: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticTextSpeechStyle = wx.StaticText(
+		self._staticTextSpeechStyle: wx.StaticText = wx.StaticText(
 			self._panelSpeech,
 			wx.ID_ANY,
 			# Translators: label for pull down allowing users to choose the "style" (version, rules) of speech for math
@@ -231,8 +231,8 @@ def __init__(self, parent):
 
 		bSizerSpeechStyle.Add(self._staticTextSpeechStyle, 0, wx.ALL, 5)
 
-		speechStyleChoices = ["xxxxxxxxxxxxxxxx"]
-		self._choiceSpeechStyle = wx.Choice(
+		speechStyleChoices: list[str] = ["xxxxxxxxxxxxxxxx"]
+		self._choiceSpeechStyle: wx.Choice = wx.Choice(
 			self._panelSpeech,
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -245,9 +245,9 @@ def __init__(self, parent):
 
 		bSizerSpeech.Add(bSizerSpeechStyle, 1, wx.EXPAND, 5)
 
-		bSizerSpeechAmount = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerSpeechAmount: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticTextSpeechAmount = wx.StaticText(
+		self._staticTextSpeechAmount: wx.StaticText = wx.StaticText(
 			self._panelSpeech,
 			wx.ID_ANY,
 			# Translators: label for pull down to specify how verbose/terse the speech should be
@@ -261,7 +261,7 @@ def __init__(self, parent):
 		bSizerSpeechAmount.Add(self._staticTextSpeechAmount, 0, wx.ALL, 5)
 
 		# Translators: options for speech verbosity.
-		speechAmountChoices = [
+		speechAmountChoices: list[str] = [
 			# Translators: options for speech verbosity -- "terse" = use less words
 			_("Terse"),
 			# Translators: options for speech verbosity -- "medium" = try to be nether too terse nor too verbose words
@@ -269,7 +269,7 @@ def __init__(self, parent):
 			# Translators: options for speech verbosity -- "verbose" = use more words
 			_("Verbose"),
 		]
-		self._choiceSpeechAmount = wx.Choice(
+		self._choiceSpeechAmount: wx.Choice = wx.Choice(
 			self._panelSpeech,
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -282,9 +282,9 @@ def __init__(self, parent):
 
 		bSizerSpeech.Add(bSizerSpeechAmount, 1, wx.EXPAND, 5)
 
-		bSizerRelativeSpeed = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerRelativeSpeed: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticTextRelativeSpeed = wx.StaticText(
+		self._staticTextRelativeSpeed: wx.StaticText = wx.StaticText(
 			self._panelSpeech,
 			wx.ID_ANY,
 			# Translators: label for slider that specifies a percentage of the normal speech rate that should be used for math
@@ -297,7 +297,7 @@ def __init__(self, parent):
 
 		bSizerRelativeSpeed.Add(self._staticTextRelativeSpeed, 0, wx.ALL, 5)
 
-		self._sliderRelativeSpeed = wx.Slider(
+		self._sliderRelativeSpeed: wx.Slider = wx.Slider(
 			self._panelSpeech,
 			wx.ID_ANY,
 			100,
@@ -312,9 +312,9 @@ def __init__(self, parent):
 
 		bSizerSpeech.Add(bSizerRelativeSpeed, 1, wx.EXPAND, 5)
 
-		bSizerPauseFactor = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerPauseFactor: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticPauseFactor = wx.StaticText(
+		self._staticPauseFactor: wx.StaticText = wx.StaticText(
 			self._panelSpeech,
 			wx.ID_ANY,
 			# Translators: label for slider that specifies relative factor to increase or decrease pauses in the math speech
@@ -327,7 +327,7 @@ def __init__(self, parent):
 
 		bSizerPauseFactor.Add(self._staticPauseFactor, 0, wx.ALL, 5)
 
-		self._sliderPauseFactor = wx.Slider(
+		self._sliderPauseFactor: wx.Slider = wx.Slider(
 			self._panelSpeech,
 			wx.ID_ANY,
 			7,
@@ -341,9 +341,9 @@ def __init__(self, parent):
 
 		bSizerSpeech.Add(bSizerPauseFactor, 1, wx.EXPAND, 5)
 
-		bSizerSpeechSound = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerSpeechSound: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._checkBoxSpeechSound = wx.CheckBox(
+		self._checkBoxSpeechSound: wx.CheckBox = wx.CheckBox(
 			self._panelSpeech,
 			wx.ID_ANY,
 			# Translators: label for check box controling a beep sound
@@ -356,9 +356,9 @@ def __init__(self, parent):
 
 		bSizerSpeech.Add(bSizerSpeechSound, 1, wx.EXPAND, 5)
 
-		bSizerSubjectArea = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerSubjectArea: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticTextSubjectArea = wx.StaticText(
+		self._staticTextSubjectArea: wx.StaticText = wx.StaticText(
 			self._panelSpeech,
 			wx.ID_ANY,
 			# Translators: label for pull down to specify a subject area (Geometry, Calculus, ...)
@@ -372,8 +372,8 @@ def __init__(self, parent):
 		bSizerSubjectArea.Add(self._staticTextSubjectArea, 0, wx.ALL, 5)
 
 		# Translators: a generic (non-specific) math subject area
-		subjectAreaChoices = [_("General")]
-		self._choiceSubjectArea = wx.Choice(
+		subjectAreaChoices: list[str] = [_("General")]
+		self._choiceSubjectArea: wx.Choice = wx.Choice(
 			self._panelSpeech,
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -386,9 +386,9 @@ def __init__(self, parent):
 
 		bSizerSpeech.Add(bSizerSubjectArea, 1, wx.EXPAND, 5)
 
-		bSizerSpeechForChemical = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerSpeechForChemical: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticTextSpeechForChemical = wx.StaticText(
+		self._staticTextSpeechForChemical: wx.StaticText = wx.StaticText(
 			self._panelSpeech,
 			wx.ID_ANY,
 			# Translators: label for pull down to specify how verbose/terse the speech should be
@@ -401,7 +401,7 @@ def __init__(self, parent):
 
 		bSizerSpeechForChemical.Add(self._staticTextSpeechForChemical, 0, wx.ALL, 5)
 
-		speechForChemicalChoices = [
+		speechForChemicalChoices: list[str] = [
 			# Translators: values for chemistry options with example speech in parenthesis
 			_("Spell it out (H 2 O)"),
 			# Translators: values for chemistry options with example speech in parenthesis (never interpret as chemistry)
@@ -424,16 +424,16 @@ def __init__(self, parent):
 		self._panelSpeech.Layout()
 		bSizerSpeech.Fit(self._panelSpeech)
 		self._simplebookPanelsCategories.AddPage(self._panelSpeech, "a page", False)
-		self._panelNavigation = wx.Panel(
+		self._panelNavigation: wx.Panel = wx.Panel(
 			self._simplebookPanelsCategories,
 			wx.ID_ANY,
 			wx.DefaultPosition,
 			wx.DefaultSize,
 			wx.BORDER_SIMPLE | wx.TAB_TRAVERSAL,
 		)
-		bSizerNavigation = wx.BoxSizer(wx.VERTICAL)
+		bSizerNavigation: wx.BoxSizer = wx.BoxSizer(wx.VERTICAL)
 
-		sbSizerNavigationMode = wx.StaticBoxSizer(
+		sbSizerNavigationMode: wx.StaticBoxSizer = wx.StaticBoxSizer(
 			wx.StaticBox(
 				self._panelNavigation,
 				wx.ID_ANY,
@@ -443,7 +443,7 @@ def __init__(self, parent):
 			wx.VERTICAL,
 		)
 
-		navigationModeChoices = [
+		navigationModeChoices: list[str] = [
 			# Translators: names of different modes of navigation. "Enhanced" mode understands math structure
 			_("Enhanced"),
 			# Translators: "Simple" walks by character expect for things like fractions, roots, and scripts
@@ -451,7 +451,7 @@ def __init__(self, parent):
 			# Translators: "Character" moves around by character, automatically moving into fractions, etc
 			_("Character"),
 		]
-		self._choiceNavigationMode = wx.Choice(
+		self._choiceNavigationMode: wx.Choice = wx.Choice(
 			sbSizerNavigationMode.GetStaticBox(),
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -462,7 +462,7 @@ def __init__(self, parent):
 		self._choiceNavigationMode.SetSelection(1)
 		sbSizerNavigationMode.Add(self._choiceNavigationMode, 0, wx.ALL, 5)
 
-		self._checkBoxResetNavigationMode = wx.CheckBox(
+		self._checkBoxResetNavigationMode: wx.CheckBox = wx.CheckBox(
 			sbSizerNavigationMode.GetStaticBox(),
 			wx.ID_ANY,
 			# Translators: label for checkbox that controls whether any changes to the navigation mode should be preserved
@@ -475,7 +475,7 @@ def __init__(self, parent):
 
 		bSizerNavigation.Add(sbSizerNavigationMode, 1, wx.EXPAND, 5)
 
-		sbSizerNavigationSpeech = wx.StaticBoxSizer(
+		sbSizerNavigationSpeech: wx.StaticBoxSizer = wx.StaticBoxSizer(
 			wx.StaticBox(
 				self._panelNavigation,
 				wx.ID_ANY,
@@ -486,13 +486,13 @@ def __init__(self, parent):
 		)
 
 		# Translators: either "Speak" the expression or give a description (overview) of the expression
-		navigationSpeechChoices = [
+		navigationSpeechChoices: list[str] = [
 			# Translators: "Speak" the expression after moving to it
 			_("Speak"),
 			# Translators: "Describe" the expression after moving to it ("overview is a synonym")
 			_("Describe/overview"),
 		]
-		self._choiceNavigationSpeech = wx.Choice(
+		self._choiceNavigationSpeech: wx.Choice = wx.Choice(
 			sbSizerNavigationSpeech.GetStaticBox(),
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -503,7 +503,7 @@ def __init__(self, parent):
 		self._choiceNavigationSpeech.SetSelection(1)
 		sbSizerNavigationSpeech.Add(self._choiceNavigationSpeech, 0, wx.ALL, 5)
 
-		self._checkBoxResetNavigationSpeech = wx.CheckBox(
+		self._checkBoxResetNavigationSpeech: wx.CheckBox = wx.CheckBox(
 			sbSizerNavigationSpeech.GetStaticBox(),
 			wx.ID_ANY,
 			# Translators: label for checkbox that controls whether any changes to the speak vs overview reading should be ignored
@@ -517,9 +517,9 @@ def __init__(self, parent):
 
 		bSizerNavigation.Add(sbSizerNavigationSpeech, 1, wx.EXPAND, 5)
 
-		bSizerNavigationZoom = wx.BoxSizer(wx.VERTICAL)
+		bSizerNavigationZoom: wx.BoxSizer = wx.BoxSizer(wx.VERTICAL)
 
-		self._checkBoxAutomaticZoom = wx.CheckBox(
+		self._checkBoxAutomaticZoom: wx.CheckBox = wx.CheckBox(
 			self._panelNavigation,
 			wx.ID_ANY,
 			# Translators: label for checkbox that controls whether arrow keys move out of fractions, etc.,
@@ -531,9 +531,9 @@ def __init__(self, parent):
 		)
 		bSizerNavigationZoom.Add(self._checkBoxAutomaticZoom, 0, wx.ALL, 5)
 
-		bSizerSpeechAmountNavigation = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerSpeechAmountNavigation: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticTextSpeechAmountNavigation = wx.StaticText(
+		self._staticTextSpeechAmountNavigation: wx.StaticText = wx.StaticText(
 			self._panelNavigation,
 			wx.ID_ANY,
 			# Translators: label for pull down to specify whether you want a terse or verbose reading of navigation commands
@@ -547,7 +547,7 @@ def __init__(self, parent):
 		bSizerSpeechAmountNavigation.Add(self._staticTextSpeechAmountNavigation, 0, wx.ALL, 5)
 
 		# Translators: options for navigation verbosity.
-		speechAmountNavigationChoices = [
+		speechAmountNavigationChoices: list[str] = [
 			# Translators: options for navigation verbosity -- "terse" = use less words
 			_("Terse"),
 			# Translators: options for navigation verbosity -- "medium" = try to be nether too terse nor too verbose words
@@ -555,7 +555,7 @@ def __init__(self, parent):
 			# Translators: options for navigation verbosity -- "verbose" = use more words
 			_("Verbose"),
 		]
-		self._choiceSpeechAmountNavigation = wx.Choice(
+		self._choiceSpeechAmountNavigation: wx.Choice = wx.Choice(
 			self._panelNavigation,
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -570,9 +570,9 @@ def __init__(self, parent):
 
 		bSizerNavigation.Add(bSizerNavigationZoom, 1, wx.EXPAND, 5)
 
-		bSizerCopyAs = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerCopyAs: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticTextCopyMathAs = wx.StaticText(
+		self._staticTextCopyMathAs: wx.StaticText = wx.StaticText(
 			self._panelNavigation,
 			wx.ID_ANY,
 			# Translators: label for pull down to specify how math will be copied to the clipboard
@@ -586,7 +586,7 @@ def __init__(self, parent):
 		bSizerCopyAs.Add(self._staticTextCopyMathAs, 0, wx.ALL, 5)
 
 		# Translators: options for copy math as.
-		copyAsChoices = [
+		copyAsChoices: list[str] = [
 			# Translators: options for Copy expression to clipboard as -- "MathML"
 			_("MathML"),
 			# Translators: options for Copy expression to clipboard as -- "LaTeX"
@@ -596,7 +596,7 @@ def __init__(self, parent):
 			# Translators: options for Copy expression to clipboard as -- speech text
 			_("Speech"),
 		]
-		self._choiceCopyAs = wx.Choice(
+		self._choiceCopyAs: wx.Choice = wx.Choice(
 			self._panelNavigation,
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -617,7 +617,7 @@ def __init__(self, parent):
 			"a page",
 			False,
 		)
-		self._panelBraille = wx.Panel(
+		self._panelBraille: wx.Panel = wx.Panel(
 			self._simplebookPanelsCategories,
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -626,9 +626,9 @@ def __init__(self, parent):
 		)
 		bSizerBraille = wx.BoxSizer(wx.VERTICAL)
 
-		bSizerBrailleMathCode = wx.BoxSizer(wx.HORIZONTAL)
+		bSizerBrailleMathCode: wx.BoxSizer = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticTextBrailleMathCode = wx.StaticText(
+		self._staticTextBrailleMathCode: wx.StaticText = wx.StaticText(
 			self._panelBraille,
 			wx.ID_ANY,
 			# Translators: label for pull down to specify which braille code to use
@@ -640,8 +640,8 @@ def __init__(self, parent):
 		self._staticTextBrailleMathCode.Wrap(-1)
 
 		bSizerBrailleMathCode.Add(self._staticTextBrailleMathCode, 0, wx.ALL, 5)
-		brailleMathCodeChoices = ["xxxxxxxxxxx"]
-		self._choiceBrailleMathCode = wx.Choice(
+		brailleMathCodeChoices: list[str] = ["xxxxxxxxxxx"]
+		self._choiceBrailleMathCode: wx.Choice = wx.Choice(
 			self._panelBraille,
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -656,7 +656,7 @@ def __init__(self, parent):
 
 		bSizerBrailleHighlights = wx.BoxSizer(wx.HORIZONTAL)
 
-		self._staticTextBrailleHighlights = wx.StaticText(
+		self._staticTextBrailleHighlights: wx.StaticText = wx.StaticText(
 			self._panelBraille,
 			wx.ID_ANY,
 			# Translators: label for pull down to specify how braille dots should be modified when navigating/selecting subexprs
@@ -669,7 +669,7 @@ def __init__(self, parent):
 
 		bSizerBrailleHighlights.Add(self._staticTextBrailleHighlights, 0, wx.ALL, 5)
 
-		brailleHighlightsChoices = [
+		brailleHighlightsChoices: list[str] = [
 			# Translators: options for using dots 7 and 8:
 			# Translators: "off" -- don't highlight
 			_("Off"),
@@ -680,7 +680,7 @@ def __init__(self, parent):
 			# Translators: "All" -- all the characters for the current navigation node use dots 7 & 8
 			_("All"),
 		]
-		self._choiceBrailleHighlights = wx.Choice(
+		self._choiceBrailleHighlights: wx.Choice = wx.Choice(
 			self._panelBraille,
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -716,7 +716,7 @@ def __init__(self, parent):
 			10,
 		)
 
-		self._staticlineAboveButtons = wx.StaticLine(
+		self._staticlineAboveButtons: wx.StaticLine = wx.StaticLine(
 			self,
 			wx.ID_ANY,
 			wx.DefaultPosition,
@@ -731,12 +731,12 @@ def __init__(self, parent):
 			5,
 		)
 
-		self._panelButtons = wx.Panel(self, wx.ID_ANY, wx.Point(-1, -1), wx.DefaultSize, 0)
+		self._panelButtons: wx.Panel = wx.Panel(self, wx.ID_ANY, wx.Point(-1, -1), wx.DefaultSize, 0)
 		bSizerButtons = wx.BoxSizer(wx.HORIZONTAL)
 
 		bSizerButtons.Add((0, 0), 1, wx.EXPAND, 5)
 
-		self._buttonOK = wx.Button(
+		self._buttonOK: wx.Button = wx.Button(
 			self._panelButtons,
 			wx.ID_ANY,
 			# Translators: dialog "ok" button
@@ -747,7 +747,7 @@ def __init__(self, parent):
 		)
 		bSizerButtons.Add(self._buttonOK, 0, wx.ALL, 5)
 
-		self._buttonCancel = wx.Button(
+		self._buttonCancel: wx.Button = wx.Button(
 			self._panelButtons,
 			wx.ID_ANY,
 			# Translators: dialog "cancel" button
@@ -758,7 +758,7 @@ def __init__(self, parent):
 		)
 		bSizerButtons.Add(self._buttonCancel, 0, wx.ALL, 5)
 
-		self._buttonApply = wx.Button(
+		self._buttonApply: wx.Button = wx.Button(
 			self._panelButtons,
 			wx.ID_ANY,
 			# Translators: dialog "apply" button
@@ -769,7 +769,7 @@ def __init__(self, parent):
 		)
 		bSizerButtons.Add(self._buttonApply, 0, wx.ALL, 5)
 
-		self._buttonReset = wx.Button(
+		self._buttonReset: wx.Button = wx.Button(
 			self._panelButtons,
 			wx.ID_ANY,
 			# Translators: button to reset all the preferences to their default values
@@ -780,7 +780,7 @@ def __init__(self, parent):
 		)
 		bSizerButtons.Add(self._buttonReset, 0, wx.ALL, 5)
 
-		self._buttonHelp = wx.Button(
+		self._buttonHelp: wx.Button = wx.Button(
 			self._panelButtons,
 			wx.ID_ANY,
 			# Translators: button to bring up a help page
@@ -828,35 +828,35 @@ def __del__(self):
 		pass
 
 	# Virtual event handlers, override them in your derived class
-	def mathCATPreferencesDialogOnCharHook(self, event):
+	def mathCATPreferencesDialogOnCharHook(self, event: wx.KeyEvent) -> None:
 		event.Skip()
 
-	def mathCATPreferencesDialogOnKeyUp(self, event):
+	def mathCATPreferencesDialogOnKeyUp(self, event: wx.KeyEvent) -> None:
 		event.Skip()
 
-	def onListBoxCategories(self, event):
+	def onListBoxCategories(self, event: wx.CommandEvent) -> None:
 		event.Skip()
 
-	def onLanguage(self, event):
+	def onLanguage(self, event: wx.CommandEvent) -> None:
 		event.Skip()
 
-	def onRelativeSpeedChanged(self, event):
+	def onRelativeSpeedChanged(self, event: wx.ScrollEvent) -> None:
 		event.Skip()
 
-	def onPauseFactorChanged(self, event):
+	def onPauseFactorChanged(self, event: wx.ScrollEvent) -> None:
 		event.Skip()
 
-	def onClickOK(self, event):
+	def onClickOK(self, event: wx.CommandEvent) -> None:
 		event.Skip()
 
-	def onClickCancel(self, event):
+	def onClickCancel(self, event: wx.CommandEvent) -> None:
 		event.Skip()
 
-	def onClickApply(self, event):
+	def onClickApply(self, event: wx.CommandEvent) -> None:
 		event.Skip()
 
-	def onClickReset(self, event):
+	def onClickReset(self, event: wx.CommandEvent) -> None:
 		event.Skip()
 
-	def onClickHelp(self, event):
+	def onClickHelp(self, event: wx.CommandEvent) -> None:
 		event.Skip()
diff --git a/addon/globalPlugins/MathCAT/__init__.py b/addon/globalPlugins/MathCAT/__init__.py
index 3945b18..cfbae9f 100644
--- a/addon/globalPlugins/MathCAT/__init__.py
+++ b/addon/globalPlugins/MathCAT/__init__.py
@@ -31,17 +31,17 @@ def __init__(self, *args, **kwargs):
 		# MathCAT.__init__(self)
 		self.addMathCATMenu()
 
-	def addMathCATMenu(self):
+	def addMathCATMenu(self) -> None:
 		if not globalVars.appArgs.secure:
 			self.preferencesMenu = mainFrame.sysTrayIcon.preferencesMenu
 			# Translators: this show up in the NVDA preferences dialog. It opens the MathCAT preferences dialog
 			self.settings = self.preferencesMenu.Append(wx.ID_ANY, _("&MathCAT Settings..."))
 			mainFrame.sysTrayIcon.Bind(wx.EVT_MENU, self.onSettings, self.settings)
 
-	def onSettings(self, evt):
+	def onSettings(self, evt: wx.CommandEvent) -> None:
 		mainFrame.popupSettingsDialog(UserInterface)
 
-	def terminate(self):
+	def terminate(self) -> None:
 		try:
 			if not globalVars.appArgs.secure:
 				self.preferencesMenu.Remove(self.settings)
diff --git a/pyproject.toml b/pyproject.toml
index 7dae399..f83a073 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -95,6 +95,7 @@ exclude = [
 # Tell pyright where to load python code from
 extraPaths = [
 	"./addon",
+	"../nvda/source",
 ]
 
 # General config
diff --git a/readme.md b/readme.md
index 476c059..5a50d4e 100644
--- a/readme.md
+++ b/readme.md
@@ -212,3 +212,22 @@ Note: there is now an option to get Vietnam's braille standard as braille output
 * A preference setting to control the duration of pausing (works with changes to relative speech rate for math)
 * Support to recognize chemistry notation and speak it appropriately
 * Translations to Indonesian and Vietnamese
+
+## Development Environment
+
+How to set up your developer environment:
+
+1. Install Python 3.11 (32-bit).
+1. Set up your virtual environment.
+    * `python -m venv .venv`
+1. Install python dependencies to `.venv`.
+    * Activate the virtual environment
+    `.venv\Scripts\activate`
+    * Install lint dependencies
+    `pip install ruff==0.8.1 pre-commit==4.0.1 pyright==1.1.396`
+1. Import NVDA code.
+    * NVDA source code needs to be discoverable to get type hints, namespace resolution, code completion, and other IDE hints.
+    * The relative path `../nvda/source` is included in the pyright configuration in `pyproject.toml`.
+    * The [NVDA repository](https://github.com/nvaccess/nvda) should be cloned into the same parent directory.
+    i.e. as a sibling to this repository.
+    Alternatively, update `../nvda/source` in `pyproject.toml` to another location where the NVDA repository has been cloned.