diff --git a/docs/codeguide.md b/docs/codeguide.md
index 402ba00be6f..0030cef319d 100644
--- a/docs/codeguide.md
+++ b/docs/codeguide.md
@@ -30,7 +30,7 @@ pos4[eTime] = 12.3;
 BoundVector pars;
 pars[eBoundLoc0] = 1.2;
 ...
-pars[eBoundPhi] = M_PI;
+pars[eBoundPhi] = std::numbers::pi;
 ...
 ```
 
diff --git a/docs/conf.py b/docs/conf.py
index 7788dad8dce..0f333f385a5 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -121,7 +121,6 @@
 nitpick_ignore = [
     ("cpp:identifier", "Acts"),
     ("cpp:identifier", "detail"),
-    ("cpp:identifier", "M_PI"),
     ("cpp:identifier", "eSize"),
     ("cpp:identifier", "eBoundSize"),
     ("cpp:identifier", "eFreeSize"),