I think a crucial part of the equation is the context. I'll give my answer with that in mind: DB engine: Postgres or otherwise MySQL, unless I'm planning to d

I think a crucial part of the equation is the context. I'll give my answer with that in mind: DB engine: Postgres or otherwise MySQL, unless I'm planning to do something specific that clearly warrants the use of something else. Too often I've regretted using something more 'exotic' for no really good reason. API layer: If this is something I'll mostly be building myself, definitely Phoenix/Elixir, unless the Rails/Ruby or Django/Python ecosystem has something that I 'need'. If hiring 'cheap' bodies is at all a concern, I'd go for Django/Python or Rails/Ruby. But at this point I'd rather hire that one developer (remote or nearby) who is itching to use Phoenix/Elixir over five of the alternative. And I think any decent Python/Ruby programmer could pick up what I started with pretty quickly. Frontend SPA: Just myself: React. If I need to work with others, possibly Vue, but most likely React still. I would probably start out with TypeScript right away, and go for the most 'vanilla' possible everything else (Webpack, Redux, React-Router, Babel, bits of Lodash perhaps). That said, while last year I would never consider this, I'd probably go for a 'good old' server-side templating approach (w/Phoenix) with some React/Vue components sprinkled in. Even with the best of devs and the best of tools, front-end just strikes me as still too fiddly, too labor-intensive, and too expensive (front-enders often cost more than back-enders, or am I wrong with that impression?) to be worth the effort. Obviously this depends entirely on what's being built though. Caching: With Phoenix, possibly none at first. Otherwise I guess something on the nginx side? Not sure if I can see this mattering too much until later in the process. PaaS: No. unless there's a good justification for it. I still lean towards using a VPS or something like that, at least until things get out of hand.