diff --git a/CHANGELOG.md b/CHANGELOG.md
index d3e0c0a..e919171 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,15 @@
 This changelog is generated by `changelog.py` using manually added semantic version tags to classify commits as breaking changes, additions or fixes.
 
 
+## [v18.0.0](https://github.com/nophead/NopSCADlib/releases/tag/v18.0.0 "show release") Breaking Changes [...](https://github.com/nophead/NopSCADlib/compare/v17.10.0...v18.0.0 "diff with v17.10.0")
+*   2021-12-12 [`970c538`](https://github.com/nophead/NopSCADlib/commit/970c5384960bb4c436cb789a1c5869c0a4adfaa5 "show commit") [C.P.](# "Chris Palmer") Updated images and readme.
+
+*   2021-12-12 [`cec790e`](https://github.com/nophead/NopSCADlib/commit/cec790ec09befd2631734cda88f3254043955638 "show commit") [M.B.](# "Martin Budden") Fixed y-carriage plain pulley and test.
+
+*   2021-11-27 [`e71db80`](https://github.com/nophead/NopSCADlib/commit/e71db80093e5131908dff4a6ecba02e5c213a7d8 "show commit") [M.B.](# "Martin Budden") Improvements to `core_xy`
+1. Better default parameters
+2. Changed `plain_idler_offset` to work in x and y, to facilitate larger idler pulleys
+
 ### [v17.10.0](https://github.com/nophead/NopSCADlib/releases/tag/v17.10.0 "show release") Additions [...](https://github.com/nophead/NopSCADlib/compare/v17.9.0...v17.10.0 "diff with v17.9.0")
 *   2021-12-12 [`c31f58a`](https://github.com/nophead/NopSCADlib/commit/c31f58a4fdf5163dc56b98e89f1a98d08cdfded2 "show commit") [C.P.](# "Chris Palmer") Updated images and readme.