How do you decide when to bump up the major, minor, or patch version of your API?

Deciding when to bump up the major, minor, or patch version of your API follows the principles of semantic versioning. Increment the patch version for backward-compatible bug fixes that do not affect the API's functionality. Bump up the minor version when you add new features or enhancements that are backward-compatible, providing new functionality without breaking existing clients. Increase the major version for changes that break backward compatibility, such as removing or altering existing endpoints or changing the response structure. Careful documentation and communication of these changes ensure users are aware of the impact, maintaining a transparent and predictable versioning strategy.

What is Semver? MAJOR version: Incremented for incompatible API changes. MINOR version: Added for backward-compatible functionality additions. PATCH version: Increased for backward-compatible bug fixes.

Semver, or Semantic Versioning, is a versioning scheme for software that aims to convey meaning about the underlying changes. It's formatted as MAJOR.MINOR.PATCH. You increment the: MAJOR version when you make incompatible API changes, MINOR version when you add functionality in a backwards-compatible manner, and PATCH version when you make backwards-compatible bug fixes. For example, if we have version 2.3.4 and we add a new feature without breaking existing functionality, we'd bump it to 2.4.0. If we fix a bug, it becomes 2.3.5. But if we make a breaking change, it becomes 3.0.0.

Major Version: Increase when making backward-incompatible changes, such as: - Removing or renaming endpoints. - Changing the behavior of existing endpoints. - Introducing significant changes that require users to modify their code. Minor Version: Increase when adding backward-compatible functionality, including: - Adding new endpoints. - Introducing optional parameters. - Enhancing existing features without breaking current usage. Patch Version: Increase for backward-compatible bug fixes, such as: - Fixing a bug in an endpoint. - Minor improvements that do not affect API usage. - Performance optimizations.

Semantic Versioning (semver) is a standardized system for assigning version numbers to software products, including APIs. The version format is X.Y.Z, where X indicates a major version, Y denotes a minor version, and Z represents a patch version. Each segment has distinct rules for incrementation: major for incompatible changes, minor for backward-compatible enhancements, and patch for backward-compatible bug fixes. Semver aims to clearly communicate the software's compatibility and stability, ensuring users and developers understand the implications of each release and can manage dependencies effectively.

Increment the major version when you make incompatible API changes. This is typically reserved for significant updates that may break existing functionality.

Increase in major version results in a lot of communication activities (deprecate your API, communicate the deprecation window) and parallel operations of both versions until the old major version will hit the stage of "sunsetting" (shutting down). Most API providers that offer multi-purpose APIs (like Open Host Services, Industry Standards etc) try to avoid increasing major versions for as long as possible. API providers with single-purpose APIs are usually not affected by this problem, because it's easy to negotiate short-living deprecation windows with that single or few API consumer teams.

An example of a change in a major API version is adding an extra field, which is a required field in the API request. So if this required field is not provided in the API request, the API call will fail. This is a major change and all the API consumers should modify the API call to add this new required field in the API request.

Deciding when to bump up the major version of your API is a significant decision. It typically happens when you introduce breaking changes that aren't backward-compatible. This could be removing a feature, changing the structure of your data, or altering the behavior of an endpoint. For example, if you have an endpoint that returns user data and you decide to remove a field from the response, that's a breaking change. Existing clients expecting that field will break, hence a major version bump is necessary. So, the rule of thumb is: if a change you're making will break existing clients, it's time to bump up the major version of your API. This way, you can introduce changes without disrupting existing users.

You increase the major version when you introduce changes that are not compatible with another major release, this will mean that your clients will have to update their software to interact with the new API. From the client's perspective, this can mean that the shape of the data received in those endpoints is completely different from what they were and thus needs new software (client update) to parse and process this new response.

A minor version increment signifies enhancements to software functionality without disrupting existing features. When releasing such updates, the software introduces new capabilities or optimizations while ensuring backward compatibility. This means that users can seamlessly adopt the new version and leverage its improvements—whether through added features, expanded integrations, or performance boosts—without altering their existing setups. Minor updates are essential for ongoing refinement and feature expansion, reflecting a commitment to gradual enhancement and user benefit.

Increase the minor version when you add functionality in a backward-compatible manner. This is used for new features that don't break existing functionality.

Minor changes usually focus on improving functionality and performance. Sometimes, minor versions might be tricky and introduce breaking changes because versioning was faulty. Therefore, check the latest API and version if you notice a software problem.

You update the minor version when your software brings improvements but it doesn't break the current API. An example could be that you add a filter option to an endpoint, nothing breaks if you don't use it.

Minor version Minor version increments in semantic versioning represent the addition of new functionality in a backwards-compatible manner. This is a powerful concept in API development as it allows for the evolution of an API without breaking existing integrations. Examples of changes that warrant a minor version increment include: Adding new endpoints or resources Introducing new optional parameters to existing endpoints Adding new fields to response payloads (as long as existing fields remain unchanged) Implementing new features that don't alter existing functionality

Patching often happens when you release a new version of API, and consumers start to signal about introduced bugs, format errors, performance, or security issues. Then, developers fix some of the bugs and patch the API holes. The documentation requires a little update, if any, primarily release notes, which are essential to inform consumers about fixes so they can start testing it.

Bump the patch version for backward-compatible bug fixes. These are minor updates that don't introduce new features but address issues.

The patch version is all about maintenance and reliability. It’s the equivalent of fixing a leak before it causes any damage. Bugs, typos, memory leaks, or small logic errors are addressed here. Patch versions are the unsung heroes that keep software stable and secure without introducing any new functionality, just refining what's already there.

Deciding when to bump up the version of your API is guided by semantic versioning. The patch version is incremented when you make backwards-compatible bug fixes. For instance, if you discover a bug in your API that doesn't alter its existing behavior but fixes an issue, you'd increment the patch version. This signals to users that the update doesn't introduce new features or breaking changes. However, if you add a new feature that doesn't disrupt the existing API, you'd increment the minor version. For major changes that make the API backwards incompatible, you'd increment the major version. This helps users understand the impact of the update on their existing integrations.

You update the path version when you're releasing a version of your software that brings some fixes. This is the most normal increase as developers are constantly improving the software. The important part is that clients who never encounter a bug won't notice any difference.

Using Semver correctly can bring significant benefits to the API development process, improving communication with users and reducing the risk of breaking changes. For projects that depend on a particular API, managing dependencies becomes much easier with Semver. Developers can specify which versions of the API they are compatible with by setting constraints in their package management systems. For example, they might specify that their project works with any version 2.x.x of the API, meaning they expect backward-compatible changes without breaking their code.

Semantic versioning serves a important role in facilitating clear and standardized communication of changes. Simply by examining the version number, developers or users can identify the nature of modifications, offering clarity on what has been altered. For example, transitioning from version 1.2.3 to 2.0.0 signals a major release with potential breaking changes, denoting a lack of backward compatibility—a valuable insight at a glance. Conversely, a shift from version 1.2.3 to 1.2.4 distinctly indicates incremental patch updates, reassuring users of maintained backward compatibility.

SemVer provides a standardized way to convey the nature of changes in a version number, enhancing communication among developers and users. By following SemVer principles, developers can make informed decisions about when to update their dependencies, and users can assess the potential impact of those updates on their systems.

Semver provides a clear and concise way to convey the nature of changes in a version number. It helps users understand the impact of upgrading to a new version and guides them on how to handle updates.

Major Version (??): Significant changes, backward-incompatible. Example: v2.0.0. Minor Version (??): New features, backward-compatible. Example: v1.1.0. Patch Version (??): Bug fixes, backward-compatible. Example: v1.0.1. Remember, SemVer helps maintain compatibility and communicates changes effectively!

Adhering to SemVer involves carefully considering the nature of changes introduced in each release. When deciding whether to bump up the major, minor, or patch version, assess the impact on backward compatibility. Major versions should be reserved for breaking changes, minor versions for new features, and patch versions for bug fixes. Documenting changes in release notes and clearly communicating with users aids in understanding the rationale behind version increments.

Follow the MAJOR.MINOR.PATCH format for version numbers. Increment the MAJOR version for incompatible changes, MINOR for added features, and PATCH for bug fixes.

SemVer isn't the only (or even the most popular) option to version your API. I really like Stripe API for its awesome docs and easy integration. It uses date-based versions like `2023-10-16`. If updating your old APIs seems daunting, why not try date-based versions? It's a simple way to improve your customers' experience starting today!

In addition to SemVer guidelines, consider the specific needs and expectations of your user base. Establish a versioning policy and communicate it transparently to users. Regularly review and update your versioning strategy based on feedback, emerging industry standards, and the evolving needs of your community. Consider using pre-release versions (e.g., alpha, beta) for features under active development to manage expectations and gather early feedback from users. This iterative approach ensures that versioning decisions align with the evolving nature of your API and the community it serves.

SemVer also allows for pre-release versions and build metadata to be appended to the version number. Pre-release versions are denoted by appending a hyphen and a series of dot-separated identifiers immediately following the patch version, indicating that the version is unstable and might not satisfy the intended compatibility requirements. Build metadata is appended by a plus sign and a series of dot-separated identifiers immediately following the patch or pre-release version, and it does not affect version precedence.

Breaking Changes: Any change that requires users to modify their code to adapt. New Features: Additional functionalities that are backward-compatible. Bug Fixes: Corrections for issues that don't alter existing functionality.

For clarity follow Semantic Versioning (SemVer). Increase the MAJOR version for incompatible API updates breaking current clients. Create a MINOR version with fresh capabilities without sacrificing compatibility. Fix PATCH by bumping it. Think about how changes might affect current clients. Should a change call for considerable code changes, a major version increment may be required. In additive features without breaking changes, a minor version bump is suitable. Patch versions are set aside for bug repairs without changing the API's behaviour.