Rulvar API reference

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Rulvar API reference / @rulvar/compat

@rulvar/compat

Frozen key-derivation profiles for journal hashVersions that leave the engine's support window, attached at engine construction through the extraDerivers option so old journals stay resumable. Independently versioned on purpose: its cadence follows the journal's compatibility history, not engine feature releases. No real profile has aged out yet at CURRENT_HASH_VERSION = 2, so today the package exports only deriverV0Synthetic, a synthetic out-of-window profile that exercises the compatibility path end to end; real profiles move in here when they retire.

Part of Rulvar, an embeddable TypeScript engine for durable, budget-bounded multi-agent LLM workflows, where a completed LLM call is never paid for twice. Full documentation: docs.rulvar.com.

Install

pnpm add @rulvar/compat

Usage

import { createEngine } from '@rulvar/core';
import { deriverV0Synthetic } from '@rulvar/compat';

const engine = createEngine({
  adapters: [/* ... */],
  // Frozen profiles keep journals with out-of-window hashVersions
  // resumable; the current engine alone resumes everything in-window.
  extraDerivers: [deriverV0Synthetic],
});

Documentation

• Journal compatibility
• Versioning
• API reference

License

Apache-2.0

Variables

Variable	Description
deriverV0Synthetic	Synthetic out-of-window profile for compatibility testing: hashVersion 0 with the round-1 projection and table. NOT a historical profile.