diff --git a/.gitignore b/.gitignore
index 0bd307639..139bf8ff3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -24,4 +24,3 @@ nbproject
 .pytest_cache/
 monkeytype.sqlite3
 output.txt
-tox.ini
diff --git a/requirements-dev.txt b/requirements-dev.txt
index f6705341c..e3030c597 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -7,6 +7,3 @@ flake8-type-checking;python_version>="3.8"      # checks for TYPE_CHECKING only
 
 pytest-icdiff
 # pytest-profiling
-
-
-tox
diff --git a/tox.ini b/tox.ini
new file mode 100644
index 000000000..8d64b929b
--- /dev/null
+++ b/tox.ini
@@ -0,0 +1,35 @@
+[tox]
+requires = tox>=4
+env_list = py{37,38,39,310,311,312}, lint, mypy, black
+
+[testenv]
+description = Run unit tests
+package = wheel
+extras = test
+pass_env = SSH_*
+commands = pytest --color=yes {posargs}
+
+[testenv:lint]
+description = Lint via pre-commit
+base_python = py39
+commands = pre-commit run --all-files
+
+[testenv:mypy]
+description = Typecheck with mypy
+base_python = py39
+commands = mypy -p git
+ignore_outcome = true
+
+[testenv:black]
+description = Check style with black
+base_python = py39
+commands = black --check --diff git
+
+# Run "tox -e html" for this. It is deliberately excluded from env_list, as
+# unlike the other environments, this one writes outside the .tox/ directory.
+[testenv:html]
+description = Build HTML documentation
+base_python = py39
+deps = -r doc/requirements.txt
+allowlist_externals = make
+commands = make -C doc html