README: updated with a word of warning

README.md

@@ -1,5 +1,19 @@
 # nix-straight.el
 
-Low-level integration to [straight.el](https://github.com/raxod502/straight.el)
+Low-level Nix integration to [straight.el](https://github.com/raxod502/straight.el)
 
 See [nix-doom-emacs](https://github.com/vlaci/nix-doom-emacs) for a usage example.
+
+There are a couple of issues you may need to be aware of:
+* Packageges which are cannot be located are (somewhat) silently ignored, only a
+  trace message appears during build.
+* Package names are dumbly inferred using the `meta.homepage` and `ename`
+  attributes. If they are both present and not match, then the packages is
+  instaled under both names in the `repos` directory.
+* Packages are symlinked from the store so all VCS related operations are
+  unavailable and package contents may differ from the ones would be installed
+  from e.g. MELPA.
+* Recipe targets are totally ignored, so there is currently no way of knowing if
+  a derivation from melpa would be used instead of a fork for example. However I
+  am planning to add a tool to generate Nix expressions from straight recipes in
+  the future.