diff --git a/pyproject.toml b/pyproject.toml
index e65998f..1e2224f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -29,3 +29,13 @@ dependencies = [
 Homepage = "https://git.pwarren.id.au/pwarren/PyFroniusReg/"
 Issues = "https://git.pwarren.id.au/pwarren/PyFroniusReg/issues"
 
+
+[tool.ruff]
+# Set the maximum line length to 79.
+line-length = 79
+
+[tool.ruff.lint]
+# Add the `line-too-long` rule to the enforced rule set. By default, Ruff omits rules that
+# overlap with the use of a formatter, like Black, but we can override this behavior by
+# explicitly adding the rule.
+extend-select = ["E501"]