Add DEV.md for development guides

Closes #358

docs/DEV.md

@@ -0,0 +1,34 @@
+# Development guides
+
+These are tips and tricks for working with the source code of TerminusDB.
+
+## Local `terminus_store_prolog`
+
+For normal usage, you can install the latest released
+[`terminus_store_prolog`][] from GitHub:
+
+
+```
+pack_install(terminus_store_prolog).
+```
+
+However, it is sometimes useful to use a local build of `terminus_store_prolog`.
+For example, suppose you are working on a change to [`terminus-store`][] and
+need to test it before release.
+
+To do this, it appears that we need to tell SWI Prolog where the
+`terminus_store_prolog` directory is and convince it that the directory is a
+pack. We do this with a symbolic link in the local pack directory. For example:
+
+```sh
+# Make the directory if it does not exist.
+mkdir -p $HOME/.local/share/swi-prolog/pack
+
+# Create a symlink to the source repository directory in the pack directory.
+ln -s <path-to>/terminus_store_prolog $HOME/.local/share/swi-prolog/pack/
+```
+
+The above works on Linux and macOS. We haven't tried it on Windows.
+
+[`terminus_store_prolog`]: https://github.com/terminusdb/terminus_store_prolog
+[`terminus-store`]: https://github.com/terminusdb/terminusdb-store