Software projects constantly evolve - features are added, bugs are fixed, and improvements are implemented over time. As a consequence, versioning comes into play. This allows us to track changes, understand the scale of modifications between releases, and make informed decisions about when and how to update our dependencies.

Unfortunately, not everyone adheres to a standardized versioning scheme. Semantic Versioning (often shortened to SemVer) provides clear guidelines, and neglecting it can lead to a world of headaches in software development.

What is Semantic Versioning?

Semantic Versioning is a widely adopted convention for assigning version numbers to software releases. A SemVer-compliant version number has the following format:

MAJOR.MINOR.PATCH

  • MAJOR: Incremented when incompatible API changes are introduced. This means that upgrading to a new major version could break your existing code if you rely on the changed functionality.
  • MINOR: Incremented when new features are added in a backward-compatible way. Upgrading within the same major version should be safe in terms of existing functionality.
  • PATCH: Incremented when backward-compatible bug fixes are made. Patch updates generally address issues without introducing feature changes or breaking compatibility.

Why Does Semantic Versioning Matter?

Let’s explore why Semantic Versioning offers significant benefits:

  • Clear communication:  Semantic Versioning gives both developers and users of software libraries/packages a simple way to understand the nature of changes between versions. A major version bump signals potential breaking changes, while a minor or patch release gives reassurance of compatibility.
  • Dependency management: Most modern package managers and build tools understand Semantic Versioning. Knowing the rules allows you to specify dependency ranges that help balance getting the latest fixes with avoiding unexpected breaks.  For example, you might indicate that your project can accept any patch update within the 2.1.x range.
  • Trust and predictability: A project that follows Semantic Versioning creates a sense of reliability. You can trust that the documented conventions are followed, making it easier to predict the impact of updates.

The Perils of Disregard

When projects and libraries don’t follow Semantic Versioning, chaos can ensue:

  • Hidden breaking changes: If a patch release (which should only contain bug fixes) suddenly introduces breaking changes, it can cause unexpected errors and downtime in dependent projects.
  • Missed updates: Without clear versioning, you might overlook important fixes or new features because the significance of an update is obscured.
  • Dependency hell: Projects that don’t follow good versioning make it incredibly difficult to manage complex dependency trees. Resolving conflicts and deciding when to update becomes a nightmare.
  • Eroded trust: Users of a library that disregards SemVer lose faith in the project. It raises doubts about the maintainers' understanding of compatibility and responsible release practices.

When a Dependency Violates Semantic Versioning

In an ideal world, everything you depend on would follow best practices. Sadly, the reality is different. Here’s what you can do when faced with a troublesome dependency:

  • Raise the issue:  Reach out to the project maintainers. Politely explain the benefits of Semantic Versioning and how breaking conventions can create problems for users. If possible, offer help in implementing a proper versioning scheme.
  • Pin versions: Be extra cautious and use precise version pinning for this dependency. This locks your project to a specific version until you can thoroughly test updates for compatibility issues.
  • Fork (with caution): In extreme cases, forking a project may be the only way to enforce Semantic Versioning practices. However,  be aware of the added maintenance burden this creates.
  • Find alternatives:  If the dependency is problematic enough, actively look for a different library or package that better respects versioning conventions.

Making Semantic Versioning a Habit

If you’re a software developer, make Semantic Versioning a cornerstone of your practices:

  • Think API first:  Before making changes, meticulously consider your project’s public API. Are you breaking existing functionality or just adding to it? Semantic Versioning hinges on this distinction.
  • Document thoroughly: Keep a clear changelog that outlines the nature of changes in each release, particularly highlighting any breaking changes that require major version updates.
  • Automate:  Use tools and scripts to automate the versioning process as much as possible. This reduces the risk of errors and makes adherence to SemVer smoother.

Call to Action

Semantic Versioning is not just a technical detail - it’s about fostering a more predictable and reliable software development ecosystem. It benefits package creators and consumers alike. Misuse of Semantic Versioning erodes trust and makes collaboration increasingly difficult.

The next time you’re updating a project, or considering a dependency, ask yourself these questions:

  • Does this project follow Semantic Versioning conventions?
  • How will this change affect users of my project or the projects I depend on?

By being mindful of versioning, we can elevate the maturity of the software development process, save ourselves and others countless hours of debugging, and create a landscape where dependencies are allies rather than liabilities.

Let’s all strive to be better citizens in the realm of software versioning.

Further Reading

If you want to take a deeper dive: