diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 41ea216..730b020 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -26,7 +26,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip wheel setuptools
-          pip install -e '.[dev]'
+          python -m pip install -e '.[dev]'
       - name: Set up API keys
         run: |
           # Azure TTS key
@@ -35,7 +35,7 @@ jobs:
           echo '${{ secrets.AWS_POLLY_KEY }}' > keys/AWSPollyServerKey.json
       - name: Test with pytest
         run: |
-          pytest --run-slow -vvvrP --log-level=DEBUG --capture=tee-sys
+          python -m pytest --run-slow -vvvrP --log-level=DEBUG --capture=tee-sys
       # - name: Lint with pre-commit hooks
       #   run: |
       #     pre-commit run --all-files
diff --git a/.gitignore b/.gitignore
index ee4effd..fdae95a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -166,3 +166,5 @@ $RECYCLE.BIN/
 
 audio/*
 keys/*
+keys*/
+env.sh
diff --git a/README.md b/README.md
index 97178ee..d9e590f 100644
--- a/README.md
+++ b/README.md
@@ -45,6 +45,15 @@ python3 -m pip install -e '.[dev]'
 Before using, place API keys for the relevant services in the `/keys` folder
 (or a folder specified by the `ICESPEAK_KEYS_DIR` environment variable).
 
+Alternately, you can set the following environment variables:
+
+```sh
+export ICESPEAK_AWSPOLLY_API_KEY=your-aws-polly-api-key
+export ICESPEAK_AZURE_API_KEY=your-azure-api-key
+export ICESPEAK_GOOGLE_API_KEY=your-google-api-key
+export ICESPEAK_OPENAI_API_KEY=your-openai-api-key
+```
+
 Output audio files are saved to the directory specified
 by the `ICESPEAK_AUDIO_DIR` environment variable.
 By default Icespeak creates the directory `<TEMP DIR>/icespeak`
diff --git a/pyproject.toml b/pyproject.toml
index 56d650c..f18c38a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,7 +1,6 @@
 [project]
 name = "icespeak"
-# Versioning is automatic (w/setuptools-scm)
-dynamic = ["version"]
+version = "0.3.7"
 description = "Icespeak - Icelandic TTS library"
 authors = [{ name = "Miðeind ehf.", email = "mideind@mideind.is" }]
 readme = { file = "README.md", content-type = "text/markdown" }
@@ -26,24 +25,24 @@ classifiers = [
 requires-python = ">=3.9"
 dependencies = [
     # "aiohttp[speedups]>=3.8.4",
-    "requests>=2.31.0",
-    "typing-extensions>=4.7.1",
+    "requests>=2.32.3",
+    "typing-extensions>=4.12.2",
     "pydantic==2.3.0",
     "pydantic-settings>=2.0.3",
     "cachetools>=5.5.0",
     # For parsing Icelandic text
-    "islenska==1.0.3",
+    "islenska<2.0.0",
     "reynir<4.0.0",
     "tokenizer<4.0.0",
     # Azure TTS
-    "azure-cognitiveservices-speech>=1.38.0",
+    "azure-cognitiveservices-speech>=1.41.1",
     # Google TTS
     #"google-cloud-texttospeech>=2.14.0",
     # AWS Polly TTS
     "botocore>=1.21.40",
     "boto3>=1.18.40",
     # OpenAI TTS
-    "openai>=1.44",
+    "openai>=1.52.2",
 ]
 
 [project.urls]
@@ -63,6 +62,7 @@ dev = [
     "ruff>=0.5.7",
     "pre-commit>=3.3.3",
     "mypy>=1.4.1",
+    "boto3-stubs>=1.35.48",
 ]
 
 # *** Configuration of tools ***
diff --git a/src/icespeak/settings.py b/src/icespeak/settings.py
index 64c4897..88e8bda 100644
--- a/src/icespeak/settings.py
+++ b/src/icespeak/settings.py
@@ -217,47 +217,61 @@ def __eq__(self, other: object):
 _kd = SETTINGS.KEYS_DIR
 if not (_kd.exists() and _kd.is_dir()):
     _LOG.warning(
-        "Keys directory missing or incorrect, TTS will not work! Set to: %s", _kd
+        "Keys directory missing or incorrect: %s", _kd
     )
-else:
-    # Load API keys, logging exceptions in level DEBUG so they aren't logged twice,
-    # as exceptions are logged as warnings when voice modules are initialized
-    try:
+
+# Load API keys, logging exceptions in level DEBUG so they aren't logged twice,
+# as exceptions are logged as warnings when voice modules are initialized
+
+# Amazon Polly
+try:
+    if key := os.getenv("ICESPEAK_AWSPOLLY_API_KEY"):
+        API_KEYS.aws = AWSPollyKey.model_validate_json(key)
+    else:
         API_KEYS.aws = AWSPollyKey.model_validate_json(
             (_kd / SETTINGS.AWSPOLLY_KEY_FILENAME).read_text().strip()
         )
-    except Exception as err:
-        _LOG.debug(
-            "Could not load AWS Polly API key, ASR with AWS Polly will not work. Error: %s",
-            err,
-        )
-    try:
+except Exception as err:
+    _LOG.debug(
+        "Could not load AWS Polly API key, ASR with AWS Polly will not work. Error: %s",
+        err,
+    )
+# Azure
+try:
+    if key := os.getenv("ICESPEAK_AZURE_API_KEY"):
+        API_KEYS.azure = AzureKey.model_validate_json(key)
+    else:
         API_KEYS.azure = AzureKey.model_validate_json(
             (_kd / SETTINGS.AZURE_KEY_FILENAME).read_text().strip()
         )
-    except Exception as err:
-        _LOG.debug(
-            "Could not load Azure API key, ASR with Azure will not work. Error: %s", err
-        )
-    try:
+except Exception as err:
+    _LOG.debug(
+        "Could not load Azure API key, ASR with Azure will not work. Error: %s", err
+    )
+# Google
+try:
+    if key := os.getenv("ICESPEAK_GOOGLE_API_KEY"):
+        API_KEYS.google = json.loads(key)
+    else:
         API_KEYS.google = json.loads(
             (_kd / SETTINGS.GOOGLE_KEY_FILENAME).read_text().strip()
         )
-    except Exception as err:
-        _LOG.debug(
-            "Could not load Google API key, ASR with Google will not work. Error: %s",
-            err,
-        )
-    try:
-        # First try to load the key from environment variable OPENAI_API_KEY
-        if key := os.getenv("OPENAI_API_KEY"):
-            API_KEYS.openai = OpenAIKey(api_key=SecretStr(key))
-        else:
-            API_KEYS.openai = OpenAIKey.model_validate_json(
-                (_kd / SETTINGS.OPENAI_KEY_FILENAME).read_text().strip()
-            )
-    except Exception as err:
-        _LOG.debug(
-            "Could not load OpenAI API key, ASR with OpenAI will not work. Error: %s",
-            err,
+except Exception as err:
+    _LOG.debug(
+        "Could not load Google API key, ASR with Google will not work. Error: %s",
+        err,
+    )
+# OpenAI
+try:
+    # First try to load the key from environment variable OPENAI_API_KEY
+    if key := os.getenv("ICESPEAK_OPENAI_API_KEY"):
+        API_KEYS.openai = OpenAIKey(api_key=SecretStr(key))
+    else:
+        API_KEYS.openai = OpenAIKey.model_validate_json(
+            (_kd / SETTINGS.OPENAI_KEY_FILENAME).read_text().strip()
         )
+except Exception as err:
+    _LOG.debug(
+        "Could not load OpenAI API key, ASR with OpenAI will not work. Error: %s",
+        err,
+    )
diff --git a/tests/test_tts.py b/tests/test_tts.py
index ecf71d1..93838ce 100644
--- a/tests/test_tts.py
+++ b/tests/test_tts.py
@@ -25,6 +25,7 @@
 from unittest.mock import MagicMock, patch
 
 import pytest
+from pydantic import SecretStr
 
 from icespeak import TTSOptions, tts_to_file
 from icespeak.settings import (
@@ -144,12 +145,12 @@ def test_OpenAI_speech_synthesis():
 def test_keys_override_in_tts_to_file():
     """Test if keys_override is correctly passed into service.text_to_speech."""
     _TEXT = "Test"
-    SERVICES["mock_service"].audio_formats = ["mp3"]
+    SERVICES["mock_service"].audio_formats = ["mp3"] # type: ignore
     keys_override = Keys(
         aws=AWSPollyKey(
-            aws_access_key_id="test",
-            aws_secret_access_key="test",
-            region_name="test",
+            aws_access_key_id=SecretStr("test"),
+            aws_secret_access_key=SecretStr("test"),
+            region_name=SecretStr("test"),
         )
     )
     opts = TTSOptions(text_format=TextFormats.TEXT, audio_format="mp3", voice="Dora")
@@ -159,7 +160,7 @@ def test_keys_override_in_tts_to_file():
         transcribe=False,
         keys_override=keys_override,
     )
-    SERVICES["mock_service"].text_to_speech.assert_called_once_with(
+    SERVICES["mock_service"].text_to_speech.assert_called_once_with( # type: ignore
         _TEXT,
         opts,
         keys_override,