MongoMapper has not been updated since Jan 25, 2012 according to its website.
MongoDB released 2.2.2 on Nov 27, 2012.
Does anyone know if MongoMapper is compatible with the newest release of MongoDB?
If it’s not, are there more actively maintained libraries?
We want to make all writes safe by default.
MongoMapper may not have had a recent release, but they have been updating the master branch and staying current with new features in MongoDB and in particular Ruby driver for MongoDB.
For example, in this commit into master you can see updates made to make use of the most recent driver (1.8) and its support for “safe” writes as the default, and to replace the now deprecated Mongo::Connection in favor of the new preferred Mongo::MongoClient class.