diff --git a/README.md b/README.md
index 9393fd91..a78ee631 100644
--- a/README.md
+++ b/README.md
@@ -77,6 +77,7 @@ The library of code included along with the zeptoforth kernel, which is present
 There is also support for loadable extras not included in any builds:
 
 * Single-cell S15.16 fixed-point numeric support
+* Complex numbers built on top of single-precision hardware floating point
 * A profiler
 * An IPv4 stack for the Raspberry Pi Pico W (aka 'zeptoIP'); for more info consult `BUILDING_AND_USING_ZEPTOIP.md`.
 * A text editor for use with files in FAT32 filesystems (aka 'zeptoed'); for more information consult `docs/extra/zeptoed.md`.