On May 26, 2026, version 2.0.0 of the JWST Calibration Pipeline will be made operational as a part of Build 12.3. This build will be used to process all new data obtained by the observatory and to reprocess all existing archival data, which takes about 4 to 5 weeks. Users can also reprocess their own data immediately using Build 12.3 and associated reference files. New calibration reference files will be used automatically with the updated software.  Please use the MAST subscription service to receive notifications when the data has been reprocessed.  

Build 12.3 represents a major update to pipeline architecture impacting all observing modes and fixes several outstanding known issues. A full list of improvements for this build can be found on the Operations Pipeline Build pages in JDox, along with a list of current known issues and future improvements. Highlights for this build include:

• Support for three new observing modes: NIRCam short wavelength grism time series (DHS), NIRISS SOSS multistripe, and MIRI Wide Field Slitless Spectroscopy.
• Automatic 1/f noise correction applied for NIRISS Imaging and WFSS, along with a new correction for SOSS time series. The corresponding rms noise in SOSS light curves has improved by a factor of 5-20.
• NIRISS SOSS spectral extraction runtime decreased by a factor of 30.
• An optional correction for resampling noise in MIRI MRS and NIRSpec IFU data cubes (adaptive_trace_model step).
• An optional correction for NIRSpec thermal picture frame artifacts (picture_frame step).

For further questions, support, or to provide input on pressing pipeline issues, observers are invited to contact the JWST Help Desk.