"Zinc" - It used to be an external package later integrated into Pharo. To check it out, download Pharo 5 from http://pharo.org/download
then try the tutorial... http://zn.stfx.eu/zn/build-and-deploy-1st-webapp/. Debug some of those examples and you'll get a look at Zinc's internals.
"Teapot" - I haven't used it but seen others in the mail list describe it as elegant. You can load it into Pharo 5 from Tools > Catalog Browser.
https://skrishnamachari.wordpress.com/2014/08/28/teapot-phar...
https://ci.inria.fr/pharo-contribution/job/EnterprisePharoBo...
Please ask questions in pharo-users if you get stuck. http://lists.pharo.org/mailman/listinfo/pharo-users_lists.ph...