About (2), I've extensively used HTTP.jl and am pretty happy with it. I don't know about exact differences to e.g. requests, but I've found it sufficient for my

About (2), I've extensively used HTTP.jl and am pretty happy with it. I don't know about exact differences to e.g. requests, but I've found it sufficient for my uses. Regarding (3), there's a daily CI job called "PkgEval" (which also runs before a new release is made) checking for regressions of julia vs. all registered packages, seeing if any break. This identifies misuse of internal APIs (which are allowed to break under semver) and actually breaking changes (which are then either undone or the packages are fixed). Additionally, you can [compat] bound julia itself in the Project.toml of your code. Those two combined should mak sure you don't have to rewrite your code. All 1.x versions are backwards compatible after all.