# Methodology change log

This append-only page records versioned changes to governed method artifacts.
The artifact snapshot below is checked before publication.

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## Current frozen method artifacts

| artifact | version | freeze hash |
| --- | --- | --- |
| codebook | 1.3.0 | `e5314e80679bc3f16e44e879083f0c168c785ea64dc7a71e33602c9ce70e270b` |
| estimand_protocol | 0.1.1 | `3d18825a6c4307dc943d6d2d3025580c0e20a36b148ff4ab13ae07e595df606c` |
| reference_frame | 2024-02 | `df8eb18bb11c43694faaa5ab6e88ec19bb8d721cd5e327572af462bcb0606808` |
| registry | 0.2.0-draft | `6d78605e336e3a75014d078b6bde8f4a134ad67d22ed43dabc12354157e11285` |

## Recorded changes

| date | artifact | old version | new version | kind | reason |
| --- | --- | --- | --- | --- | --- |
| 2026-07-17 | registry | unfrozen | 0.2.0-draft | freeze | Segment Registry freeze |
| 2026-07-23 | registry | 0.2.0-draft | 0.2.0-draft | freeze | Segment Registry freeze |
| 2026-07-23 | registry | 0.2.0-draft | 0.2.0-draft | freeze | Segment Registry freeze |
| 2026-08-08 | reference_frame | unfrozen | 2024-02 | freeze | Reference Frame freeze |
| 2026-08-08 | reference_frame | 2024-02 | 2024-01 | freeze | Reference Frame freeze |
| 2026-08-08 | reference_frame | 2024-02 | 2024-02 | freeze | Reference Frame freeze |