PG Gem fails on Mac OS 11.x (Big Sur)

If after installing pg gem in your ruby project and you get the following error with the pg gem

```
Library not loaded: libpq.5.dylib
```

You can fix the linking issues by running the following commands:

```bash
cd ~/[your ruby path]/versions/2.7.2/lib/ruby/gems/2.7.0/gems/pg-1.2.3/lib

install_name_tool -change libpq.5.dylib /Library/PostgreSQL/12/lib/libpq.5.12.dylib pg_ext.bundle
```

You may need to modify the commands above to suite your ruby manager and currently installed versions.

nelsonpascoal
April 6, 2021