API stability is one of Scrapy major goals.
When Scrapy reaches 1.0, each release will consist of three version numbers:
- major - big, backwards-incompatible changes
- minor - new features and backwards-compatible changes
- micro - bug fixes only
Until Scrapy reaches 1.0, minor releases (0.7, 0.8, etc) will follow the same policy as major releases.
Sometimes the micro version can be omitted, for brevity, when it’s not relevant.
Methods or functions that start with a single dash (_) are private and should never be relied as stable. Besides those, the plan is to stabilize and document the entire API, as we approach the 1.0 release.
Also, keep in mind that stable doesn’t mean complete: stable APIs could grow new methods or functionality but the existing methods should keep working the same way.