SessionKey Schema-ID Canonicalization

Compatibility note for fallback SessionKey schema IDs across runtime and tooling.

Updated 2026-05-09Edit this page

SessionKey Schema-ID Canonicalization

Summary

Vango now computes fallback SessionKey schema IDs from one canonical type grammar in both runtime and tooling. This removes drift between runtime reflect formatting and tooling go/types formatting.

Why This Changed

Some valid SessionKey[T] declarations could previously panic at startup with a fingerprint mismatch because runtime and tooling were formatting certain types differently.

This was most visible with:

  • unnamed composite types

  • alias-adjacent forms

  • fallback schema-ID paths that did not share a single canonical formatter

Operational Impact

This is an intentional canonicalization break.

  • Some SessionKey fingerprints may change once.

  • vango state plan may classify affected deploys as schema-incompatible.

  • The normal cold-deploy acknowledgement flow may be required.

Required Workflow

shell
1vango state plan
2vango state apply
3vango gen bindings

Then commit the updated manifest, schema, and bindings artifacts.

Diagnostics Improvement

Binding mismatch output now includes:

  • key name

  • runtime schema ID

  • runtime fingerprint

  • binding fingerprint

  • an actionable remediation hint