MongoDB Node.js Driver 4.1.0 Released

The MongoDB Node.js team is pleased to announce version 4.1.0 of the mongodb package!

Release Highlights

This release includes load balancer support, intended for use with the beta Serverless platform. When using the driver with Serverless, the SRV URI will automatically put the driver into this mode. When wanting to use a non-SRV URI one must add the loadBalanced=true option to the URI to put the driver into this mode. Being in this mode enables the driver to properly route transactions and cursors to the correct service behind the load balancer.

The release also fixes an important bug where the original release of the v4 driver enabled command monitoring by default, which caused many reported observations of performance degradation when upgrading from v3 of the driver. Command monitoring is now once again disabled by default and must be enabled by passing in { monitorCommands: true } to the client if desired.


  • NODE-2843: implement sessions advanceClusterTime method (#2920) (1fd0244)
  • NODE-3011: Load Balancer Support (#2909) (c554a7a)

Bug Fixes

  • NODE-2883: Aggregate Operation should not require parent parameter (#2918) (dc6e2d6)
  • NODE-3058: accept null or undefined anywhere we permit nullish values (#2921) (b42a1b4)
  • NODE-3441: fix typings for createIndexes (#2915) (f87f376)
  • NODE-3442: AsyncIterator has incorrect return type (#2916) (4a10389)
  • NODE-3452: readonly filters not permitted by typings (#2927) (ce51e78)
  • NODE-3510: omit incorrect | void in declaration of Promise overload of rename() (#2922) (58c1e84)
  • NODE-3513: default command monitoring to off (#2926) (3c60245)


We invite you to try the mongodb library immediately, and report any issues to the NODE project.