diff --git a/README.md b/README.md
index 239c585..8ce7ca5 100644
--- a/README.md
+++ b/README.md
@@ -161,6 +161,8 @@ chmod +x runwt.sh
 ./runwt.sh tough.ktx2
 ```
 
+Unfortunately, WASM WASI executables have tradeoffs vs. native executables: Limited memory and slower performance. 32-bit WASM WASI memory constraints limit the maximum image/texture size that can be compressed to XUASTC LDR to around 4 megapixels. For web, we can support both WASM and WASM64, which relaxes the memory constraints. As far as we know as of 2/2026, the WASI SDK still [doesn't officially support the wasm64-wasi target](https://github.com/WebAssembly/wasi-sdk/issues/212), but once it does we'll support it.
+
 ----
 
 Building (Native)