The question is: Solving what problems, at what scale? If you're a profitable company with a sizeable userbase, just buy Salesforce. It's clunky, it's expensiv

The question is: Solving what problems, at what scale? If you're a profitable company with a sizeable userbase, just buy Salesforce. It's clunky, it's expensive, but you can find contractors really easily to make it do whatever it is you want. Or you can learn the Salesforce platform yourself and build your final CRM on top of that. Welcome to enterprise IT! If you're a scrappy start-up, or non-profit, with a small number of people to serve, you can use whatever you're most comfortable with. A single database (perhaps with hot replica,) a single application server (perhaps with load balancing for good measure) and you have everything you need. Use whatever you already know. PHP and Bootstrap? Ruby and Rails? Node and Angular? Doesn't matter. If I were in the middle area -- successful company, lots of customers, but not actually at the point where I need the Salesforce behind-covering and easy contractor access -- then I would probably use React for the front-end GUI, and Haskell with Warp for the back-end services, hosted on top of MySQL or Postgres, with Redis for data caching, plus some scripts to make creating bread-and-butter tables/indices/queries simpler and less repetitive. Like the poster above, I kind of like having an "escape column" for "annottation data" stored in JSON, although it can simply be a plain TEXT. As long as you don't need indexing, it makes adding new columns easy even if you have a table that's too big to change online.