Update welcome.mdx (#96)

Update w/ notes on version compatibility.

Author: brianc

content/welcome.mdx

@@ -26,6 +26,10 @@ node-postgres continued development and support is made possible by the many [su
 
 If you or your company would like to sponsor node-postgres stop by [github sponsors](https://github.com/sponsors/brianc) and sign up or feel free to [email me](mailto:[email protected]) if you want to add your logo to the documentation or discuss higher tiers of sponsorship!
 
+# Version compatibility
+
+node-postgres strives to be compatible with all recent lts versions of node & the most recent "stable" version.  At the time of this writing node-postgres is compatible with node 8.x, 10.x, 12.x and 14.x  To use node >= 14.x you will need to install `[email protected]` or later due to some internal stream changes on the node 14 branch.  Dropping support for an old node lts version will always be considered a breaking change in node-postgres and will be done on _major_ version number changes only, and we will try to keep support for 8.x for as long as reasonably possible.
+
 ## Getting started
 
 This is the simplest possible way to connect, query, and disconnect with async/await: