More specifically, I’m thinking about two different modes of development for a library (private to the company) that’s already relied upon by other libraries and applications:

  1. Rapidly develop the library “in isolation” without being slowed down by keeping all of the users in sync. This causes more divergence and merge effort the longer you wait to upgrade users.
  2. Make all changes in lock-step with users, keeping everyone in sync for every change that is made. This will be slower and might result in wasted work if experimental changes are not successful.

As a side note: I believe these approaches are similar in spirit to the continuum of microservices vs monoliths.

Speaking from recent experience, I feel like I’m repeatedly finding that users of my library have built towers upon obsolete APIs, because there have been multiple phases of experimentation that necessitated large changes. So with each change, large amounts of code need to be rewritten.

I still think that approach #1 was justified during the early stages of the project, since I wanted to identify all of the design problems as quickly as possible through iteration. But as the API is getting closer to stabilization, I think I need to switch to mode #2.

How do you know when is the right time to switch? Are there any good strategies for avoiding painful upgrades?

  • kersplort
    2·
    1 year ago

    Get good at the three point turn.

    • Add the new code path/behavior. Release - this can be a minor version in semver.
    • Mark the old code path or behavior as deprecated. Release - this can be another minor version.
      • In between here, clean up any dependencies or give your users time to clean up.
    • Remove the old code path or behavior. Release. If you’re using semver, this is the major version change.

    This is a stable way to make changes on any system that has a dependency on another platform, repository, or system. It’s good practice for anything on the web, as users may have logged in or long running sessions, and it works for systems that call each other and get released on different cadences.