diff --git a/README.md b/README.md
index 43f4efc..4eb0256 100644
--- a/README.md
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@@ -118,3 +118,5 @@ if (result == COBS_RET_SUCCESS) {
 ## Developing
 
 `nanocobs` uses [catch2](https://github.com/catchorg/Catch2) for unit and functional testing; its unified mega-header is checked in to the `tests` directory. To build and run all tests, just run `make -j` from a terminal after cloning. It's really amazing how long it takes to compile Catch2, thanks C++!
+
+The presubmit workflow compiles `nanocobs` on macOS, Linux (gcc) 32/64, Windows (msvc) 32/64. It also builds weekly against a fresh docker image so I know when newer stricter compilers break it.