diff --git a/.readthedocs.yml b/.readthedocs.yml
new file mode 100644
index 00000000..ee2527a4
--- /dev/null
+++ b/.readthedocs.yml
@@ -0,0 +1,14 @@
+# .readthedocs.yml
+
+version: 2
+
+sphinx:
+  configuration: docs/conf.py
+
+python:
+  version: 3.7
+  install:
+    - method: pip
+      path: .
+      extra_requirements:
+        - docs
\ No newline at end of file
diff --git a/poetry.lock b/poetry.lock
index 964d3b6f..732f1b36 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -2,8 +2,8 @@
 name = "alabaster"
 version = "0.7.12"
 description = "A configurable sidebar-enabled Sphinx theme"
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = "*"
 
 [[package]]
@@ -32,8 +32,8 @@ tests_no_zope = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>
 name = "babel"
 version = "2.9.1"
 description = "Internationalization utilities"
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 
 [package.dependencies]
@@ -43,16 +43,16 @@ pytz = ">=2015.7"
 name = "certifi"
 version = "2021.10.8"
 description = "Python package for providing Mozilla's CA Bundle."
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = "*"
 
 [[package]]
 name = "charset-normalizer"
 version = "2.0.10"
 description = "The Real First Universal Charset Detector. Open, modern and actively maintained alternative to Chardet."
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=3.5.0"
 
 [package.extras]
@@ -62,7 +62,7 @@ unicode_backport = ["unicodedata2"]
 name = "colorama"
 version = "0.4.4"
 description = "Cross-platform colored terminal text."
-category = "dev"
+category = "main"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
 
@@ -70,24 +70,24 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
 name = "docutils"
 version = "0.17.1"
 description = "Docutils -- Python Documentation Utilities"
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
 
 [[package]]
 name = "idna"
 version = "3.3"
 description = "Internationalized Domain Names in Applications (IDNA)"
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=3.5"
 
 [[package]]
 name = "imagesize"
 version = "1.3.0"
 description = "Getting image size from png/jpeg/jpeg2000/gif file"
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 
 [[package]]
@@ -119,8 +119,8 @@ python-versions = "*"
 name = "jinja2"
 version = "3.0.3"
 description = "A very fast and expressive template engine."
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=3.6"
 
 [package.dependencies]
@@ -133,8 +133,8 @@ i18n = ["Babel (>=2.7)"]
 name = "markupsafe"
 version = "2.0.1"
 description = "Safely add untrusted strings to HTML/XML markup."
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=3.6"
 
 [[package]]
@@ -157,7 +157,7 @@ python-versions = ">=3.8"
 name = "packaging"
 version = "21.3"
 description = "Core utilities for Python packages"
-category = "dev"
+category = "main"
 optional = false
 python-versions = ">=3.6"
 
@@ -191,8 +191,8 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
 name = "pygments"
 version = "2.11.2"
 description = "Pygments is a syntax highlighting package written in Python."
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=3.5"
 
 [[package]]
@@ -208,9 +208,9 @@ importlib_metadata = {version = ">=1.6", markers = "python_version < \"3.8\""}
 
 [[package]]
 name = "pyparsing"
-version = "3.0.6"
+version = "3.0.7"
 description = "Python parsing module"
-category = "dev"
+category = "main"
 optional = false
 python-versions = ">=3.6"
 
@@ -243,16 +243,16 @@ testing = ["argcomplete", "hypothesis (>=3.56)", "mock", "nose", "requests", "xm
 name = "pytz"
 version = "2021.3"
 description = "World timezone definitions, modern and historical"
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = "*"
 
 [[package]]
 name = "requests"
 version = "2.27.1"
 description = "Python HTTP for Humans."
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, !=3.5.*"
 
 [package.dependencies]
@@ -277,16 +277,16 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*"
 name = "snowballstemmer"
 version = "2.2.0"
 description = "This package provides 29 stemmers for 28 languages generated from Snowball algorithms."
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = "*"
 
 [[package]]
 name = "sphinx"
 version = "4.4.0"
 description = "Python documentation generator"
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=3.6"
 
 [package.dependencies]
@@ -317,8 +317,8 @@ test = ["pytest", "pytest-cov", "html5lib", "cython", "typed-ast"]
 name = "sphinx-rtd-theme"
 version = "1.0.0"
 description = "Read the Docs theme for Sphinx"
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=2.7,!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*"
 
 [package.dependencies]
@@ -332,8 +332,8 @@ dev = ["transifex-client", "sphinxcontrib-httpdomain", "bump2version"]
 name = "sphinxcontrib-applehelp"
 version = "1.0.2"
 description = "sphinxcontrib-applehelp is a sphinx extension which outputs Apple help books"
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=3.5"
 
 [package.extras]
@@ -344,8 +344,8 @@ test = ["pytest"]
 name = "sphinxcontrib-devhelp"
 version = "1.0.2"
 description = "sphinxcontrib-devhelp is a sphinx extension which outputs Devhelp document."
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=3.5"
 
 [package.extras]
@@ -356,8 +356,8 @@ test = ["pytest"]
 name = "sphinxcontrib-htmlhelp"
 version = "2.0.0"
 description = "sphinxcontrib-htmlhelp is a sphinx extension which renders HTML help files"
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=3.6"
 
 [package.extras]
@@ -368,8 +368,8 @@ test = ["pytest", "html5lib"]
 name = "sphinxcontrib-jsmath"
 version = "1.0.1"
 description = "A sphinx extension which renders display math in HTML via JavaScript"
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=3.5"
 
 [package.extras]
@@ -379,8 +379,8 @@ test = ["pytest", "flake8", "mypy"]
 name = "sphinxcontrib-qthelp"
 version = "1.0.3"
 description = "sphinxcontrib-qthelp is a sphinx extension which outputs QtHelp document."
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=3.5"
 
 [package.extras]
@@ -391,8 +391,8 @@ test = ["pytest"]
 name = "sphinxcontrib-serializinghtml"
 version = "1.1.5"
 description = "sphinxcontrib-serializinghtml is a sphinx extension which outputs \"serialized\" HTML files (json and pickle)."
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=3.5"
 
 [package.extras]
@@ -419,8 +419,8 @@ python-versions = ">=3.6"
 name = "urllib3"
 version = "1.26.8"
 description = "HTTP library with thread-safe connection pooling, file post, and more."
-category = "dev"
-optional = false
+category = "main"
+optional = true
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, <4"
 
 [package.extras]
@@ -440,10 +440,13 @@ python-versions = ">=3.7"
 docs = ["sphinx", "jaraco.packaging (>=8.2)", "rst.linker (>=1.9)"]
 testing = ["pytest (>=6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytest-cov", "pytest-enabler (>=1.0.1)", "jaraco.itertools", "func-timeout", "pytest-black (>=0.3.7)", "pytest-mypy"]
 
+[extras]
+docs = ["Sphinx", "sphinx_rtd_theme"]
+
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.7"
-content-hash = "de1bd0c5bd3a0e5d582acde9fdbbba7df10c3708df07dcc7ab4ccb8e08e8e0f6"
+content-hash = "4d7fad92ab73f78d18f50fcfe025790116d7eb3812bc0cf2e83f89c03db59166"
 
 [metadata.files]
 alabaster = [
@@ -644,8 +647,8 @@ pykka = [
     {file = "pykka-3.0.2.tar.gz", hash = "sha256:15da050b4f37babc0782803ef8922a0070d970eb4da2a5b88b098795aa8a3263"},
 ]
 pyparsing = [
-    {file = "pyparsing-3.0.6-py3-none-any.whl", hash = "sha256:04ff808a5b90911829c55c4e26f75fa5ca8a2f5f36aa3a51f68e27033341d3e4"},
-    {file = "pyparsing-3.0.6.tar.gz", hash = "sha256:d9bdec0013ef1eb5a84ab39a3b3868911598afa494f5faa038647101504e2b81"},
+    {file = "pyparsing-3.0.7-py3-none-any.whl", hash = "sha256:a6c06a88f252e6c322f65faf8f418b16213b51bdfaece0524c1c1bc30c63c484"},
+    {file = "pyparsing-3.0.7.tar.gz", hash = "sha256:18ee9022775d270c55187733956460083db60b37d0d0fb357445f3094eed3eea"},
 ]
 pytest = [
     {file = "pytest-6.2.5-py3-none-any.whl", hash = "sha256:7310f8d27bc79ced999e760ca304d69f6ba6c6649c0b60fb0e04a4a77cacc134"},
diff --git a/pyproject.toml b/pyproject.toml
index 6616f044..1ddb025b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -30,23 +30,28 @@ exclude = ["nidaqmx/tests"]
 
 [tool.poetry.dependencies]
 python = "^3.7"
+# Need two version blocks to match numpy's changing version requirements.
 numpy = [
-    {version = "1.21.5", python = "~3.7"},
-    {version = "^1.22", python = "^3.8"}
+    {version="1.21.5", python = "~3.7"},
+    {version="^1.22", python = "^3.8"}
 ]
 six = "^1.16"
 # This functionality was merged into python stdlib beginning in 3.8
-importlib_metadata = {version = "^4.10", python="~3.7" }
+importlib_metadata = {version="^4.10", python="~3.7"}
+# Documentation, must be in main dependencies (but optional) list for
+# readthedocs integration.
+# See https://github.com/readthedocs/readthedocs.org/issues/4912.
+Sphinx = {version="^4.4", optional=true}
+sphinx_rtd_theme = {version="^1.0", optional=true}
+
+[tool.poetry.extras]
+docs = ["sphinx", "sphinx_rtd_theme"]
 
 [tool.poetry.dev-dependencies]
 # Test
 pytest = "^6.2"
 pykka = "^3.0"
 
-# Documentation
-Sphinx = "^4.4"
-sphinx_rtd_theme = "^1.0"
-
 [build-system]
 requires = ["poetry>=1.1.12"]
 build-backend = "poetry.masonry.api"
\ No newline at end of file