I'm a small town guy who mostly works on small (town) teams, so I've often done database, application, and client. The very edges are mostly static albeit evol

I'm a small town guy who mostly works on small (town) teams, so I've often done database, application, and client. The very edges are mostly static albeit evolving... HTML has been improved, CSS much more capable, and JavaScript has grown (and been repackaged) but client development on the very edge isn't too different. The database and the bones of SQL have not changed drastically (though you can choose NoSQL and use JSON, which is very different!) But to your point, the application layer actually has changed a lot. I started out writing ColdFusion applications, then classic ASP, then .NET 1.1/2.0 through 4.8 and a pinch of .NET Core 2.0+. But also NodeJS and Python and dozens and dozens I haven't touched. However, the software development skills that are (semi-)permanent apply, while the particular expiring flavors change with the seasons. In some ways, JavaScript has been the most constant through my career, though how I've used it has been all over the map, from little scripts in a HEAD tag, to jQuery applications, to NodeJS server applications, to TypeScript client applications.