Marten 1.2 — Improved Linq support and way more polish

Marten is a library for .Net that turns Postgresql into a document database and event store.

I just published the Marten 1.2 release to Nuget. While I hoped to fit a lot more new functionality into this release, 1.2 really just adds a lot more polish to Marten by fixing several bugs, makes some performance improvements based on my company’s trial by fire usage of Marten during our peak “season”, and by largely reworking the internals of the Linq support.

Marten continues to have a vibrant community of interested folks and contributors that are helping push the project on. Probably missing some names, but I’d like to call out James Hopper, jokokko, Barry Hagan, Alexander Langer, and Robin van der Knaap for their contributions to this release. I’d also like to thank all of you who have opened and commented on Github issues to help improve Marten. If this all keeps up long enough, I may finally stop being so cynical about OSS on the .Net platform;)

Here’s the entire list of changes from the GitHub milestone. The highlights of the 1.2 release are:

Support for the SelectMany() operator in Linq queries (this story spurred an absurd amount of rework in our Linq support that I think will make it easier to add more features in subsequent releases)
Distinct() Linq query support
Named parameter usage in user supplied queries
Better logging and exception messages
Marten’s sequential Guid algorithm was corrected to order consistently with Postgresql. This should result in better write performance in Marten usage with Guid id’s.
Marten tries harder to warn you when you use unsupported Linq operators
Several improvements to querying against child collections
The ability to use event metadata in the built in aggregation projections
Cleaned up some of the database connection mechanics to stop mixing blocking and async calls and makes Marten much more aggressive about closing database connections

What’s Next?

I’m not 100% sure I want to commit to another new release before the holiday season, but 1.3 is looking like it’s going to be a lot of improvements for querying against multiple documents, new types of Select() transformations, and working over the internals to optimize performance.

The tentative list of 1.3 enhancements can be seen here.