---
issue: 097
title: "Backend: validTransitions map missing 'in_negotiation' key"
severity: medium
domain: Marketplace
labels: [bug, backend, state-machine]
status: open
created: 2026-05-30
source: Full Codebase Audit 2026-05-30
---

# Backend: validTransitions map missing 'in_negotiation' key

**Severity:** medium
**Domain:** Marketplace
**Labels:** bug, backend, state-machine

## Description

`marketplaceController.ts:544-555` defines a `validTransitions` map for PurchaseRequest status transitions but has no entry for `'in_negotiation'`. A PurchaseRequest in the `in_negotiation` state cannot transition to any other state via this validator.

## Options

1. Add `'in_negotiation'` with its allowed next statuses (e.g. `payment`, `cancelled`).
2. Treat missing key as 'allow same-tier transitions' default.
3. Derive transitions from `STATUS_PROGRESSION_ORDER` instead of a hand-maintained map.

## Recommendation

Add an explicit `'in_negotiation'` entry with the correct next statuses. Requires product/state-machine confirmation of valid transitions.

## Affected Files

- `backend/src/services/marketplace/marketplaceController.ts:544-555`

## References

- [Full Codebase Audit 2026-05-30](../09%20-%20Audits/Full%20Codebase%20Audit%20-%202026-05-30.md) — DEC-35