# Sprint 154 Plan: Recovery, Rollback, and Safety Across Adapters

## Context

Sprint 154 hardens reliability by guaranteeing transactional behavior and safe
recovery paths for constructive operations across all supported adapters.

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## Goals

1. Add transactional apply semantics for constructive operations
2. Support resumable loop state after interruption/failure
3. Enforce rollback guarantees on failed merge/build/test stages
4. Validate crash and partial-failure scenarios across languages

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## Steps

### Step 1779: Constructive transaction schema (10 tests)
### Step 1780: Stage checkpoint and resume model (10 tests)
### Step 1781: Cross-language rollback policy engine model (10 tests)
### Step 1782: Failure injection and safety validation model (10 tests)
### Step 1783: `whetstone_begin_constructive_transaction` MCP tool (8 tests)
### Step 1784: `whetstone_resume_constructive_transaction` MCP tool (8 tests)
### Step 1785: `whetstone_rollback_constructive_transaction` MCP tool (8 tests)
### Step 1786: Recovery safety packet model (8 tests)
### Step 1787: Reliability and rollback report artifact (8 tests)
### Step 1788: Sprint 154 integration summary + regression (8 tests)

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## Architecture Gate

- Transaction boundaries must be explicit and deterministic
- Rollback must restore prior consistent state for every failed stage
- Resume paths must preserve provenance and determinism guarantees
- Max 600 lines per header