Learn about the String-Based Filter Configuration API RFC - Scot Breitenfeld Call the Doctor 5/12/26
Scot Breitenfeld will host Call the Doctor on Tuesday, May 12. He’ll talk about the recent RFC, “String-Based Filter Configuration API,” which was also covered during the last Working Group meeting. In this session, we will explore alternatives to the custom parser outlined in the current RFC and discuss any remaining RFC topics of interest.
For more info on this RFC, check out these resources:
To join, just jump on the zoom:
Launch Meeting - Zoom
May 12, 2026,12:20 p.m. central time US/Canada
In this week’s “Call the Doctor,” Scot Breitenfeld walked us through a major update to how we configure filters in HDF5. We are moving away from the “magic numbers” of cd_values toward a standardized, human-readable approach using TOML.
Relevant Links:
Today I Learned (TIL):
The decision to use TOML over a custom key-value parser wasn’t just about ease of use—it was about sustainability. By adopting a standard like TOML, the HDF5 library gets native support for data types (integers, floats, booleans) and nesting “for free,” without the HDF Group having to maintain a custom grammar spec forever.
For a deeper dive into the new API signatures and how this affects plugin authors, check out the full blog post and cleaned transcript.
