Do companies bring freelancers in for interviews without there being some communication about the tech/stack for which they are looking for expertise? I get th

Do companies bring freelancers in for interviews without there being some communication about the tech/stack for which they are looking for expertise? I get the OP's point that all of the tech/stacks are just tools in the box: you use the right tool for the job without having any sentimental or emotional attachment to it. That said, if interviewers are skeptical about someone with multi-stack development you should be able to leverage that by emphasizing that seeing how problems are solved in different stacks gives you unique insight into the hidden gotchas that aren't apparent to devs wedded to a single stack. I did several years of contracting (all in C#) and was able to explain that I had seen Entity Framework implemented in five different ways and could speak the advantages/disadvantages of each set of implementation decisions (and would be happy to mentor the team on such matters). Ultimately the business needs a problem solved and you can solve the problem. To build on the analogy of another commenter: you can bake the bread they need whether they have an electric oven, gas oven, wood-fired pizza oven or just a bonfire in an open field: you've done it all. Not only can you help them solve their immediate problem but you can advise them on how best to position them to avoid future problems they don't realize they are about to run into because in 20 years you've pretty much seen it all.