Glossary · Automation software engineering and architecture
Patch version
Also known as: Patch level, Bugfix version
German: Patch-Version
In software versioning, the patch version is the third number of a version identifier such as 3.1.4; under semantic versioning it is incremented for backward-compatible bug fixes only.
- Software engineering
In one sentence
The patch version is the third number of a version identifier; semantic versioning raises it for backward-compatible bug fixes only.
Example
Firmware 4.2.1 fixes a wrong unit in a diagnostic message of version 4.2.0 without adding features, so it is released as a patch version.
How it applies
- Engineering: A patch release contains fixes only. Mixing new features into it breaks the expectations of users who install patches with little testing.
- Maintenance: Operators apply patch versions more readily than minor or major ones; Patch management processes still require checking the fix list against the plant's use.
- Documentation: Every patch needs a Release note listing the fixed defects in user terms. The manual itself rarely changes, but corrected behavior that the manual described wrongly must be updated.
Patch version vs. security patch
The patch version is a numbering convention. A security patch is a fix for a vulnerability, which may be released as a patch version, but also as a hotfix outside the regular numbering.