Thank you! The error I get on the JS console is: Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at http://localhost:5000/emperl.wasm. (Reason: CORS header ‘Access-Control-Allow-Origin’ missing). I addressed that issue in 4a7dd5709b, which is unfortunately not part of v0.07-beta.

For development, I would suggest this instead:

$ git clone https://github.com/haukex/webperl.git
$ wget https://github.com/haukex/webperl/releases/download/v0.07-beta/
+webperl_prebuilt_v0.07-beta.zip
$ unzip webperl_prebuilt_v0.07-beta.zip
$ cp webperl_prebuilt_v0.07-beta/emperl.* webperl/web/
$ cd webperl
$ plackup web/webperl.psgi
[download]

Then browse to http://localhost:5000/democode/demo.html.