Is there a way to connect to PostgreSQL in ArcCatalog without SDE? I came across this post from 2011 that suggested using zigGIS but I can’t find a working link to the program.

A little background: At my work we have a small GIS department (3 people) and our current process is to create file geodatabases for each client. The main issue is that we work in a high-transaction environment and we are constantly locking each other when we work on the same project. This is extremely annoying so we're trying to move to a relational database like PostgreSQL.

While it would be nice to switch over to SDE ESRI Canada gave us a quote that is way too much for a staff of three people (something like 40k install and 20k/year maintenance)

Also if anyone uses PostGIS as your main form of data storage, what GIS program do you use?