microversioned

Microversioning is a software design pattern used to manage backward compatibility in evolving systems while allowing incremental updates. It involves assigning a version number to specific features or behaviors within a system, enabling older versions to remain functional alongside newer ones. This approach is particularly useful in distributed systems, APIs, and protocols where maintaining compatibility with existing clients or services is critical.

The concept of microversioning differs from traditional versioning, where an entire system is updated as a single unit. Instead, microversioning isolates changes to particular components or functionalities, allowing developers to introduce new features or modifications without disrupting existing functionality. This granular control helps mitigate risks associated with large-scale updates and simplifies rollback procedures if issues arise.

Microversioning is commonly implemented through versioned endpoints, headers, or query parameters in APIs. For example, an API might include a version identifier in the request path (e.g., `/v1/resource`, `/v2/resource`) or as a header (e.g., `Accept-Version: 2`). This ensures that clients can explicitly request the version of the API they are compatible with, while servers can serve the appropriate response.

Advantages of microversioning include improved backward compatibility, reduced downtime during updates, and the ability to experiment with new features without affecting all users. However, it also introduces complexity in version management, as developers must carefully document and maintain multiple versions. Additionally, clients must be aware of versioning to avoid unintended behavior when interacting with newer or older versions of the system.

Microversioning is widely adopted in modern software architectures, particularly in cloud services, microservices, and open-source projects where continuous evolution is essential. Examples include GitHub’s API, which supports multiple versions to accommodate different client requirements, and some blockchain platforms that use microversioning to manage protocol upgrades.