Validation isn’t a step.
It’s the loop.
Every other AI dev shop ships code that looked right on the generation pass and hoped for the best. Parity runs validation before code is written, during every generation, and after the deploy ships. Four layers, running in a loop, catching regressions before they reach your users.
A validation surface at every point
code could regress.
- 01
Spec-driven generation
Every feature begins as an executable spec — a markdown document with acceptance criteria the validators can actually run against.
Vibes-based prompting produces vibes-based code. We convert intent into structured specs before any agent writes a line. The spec is the contract between the human intent and the machine output.
spec/checkout-flow.mdmarkdown # Feature: Guest Checkout Flow### Acceptance Criteria1. User lands on /checkout with cart persisted 2. Email field validated against RFC-53223. Payment tokenized client-side, never stored 4. Success page LCP < 1.2s5. Accessibility: WCAG 2.2 AA## Validators - eval/visual-hierarchy.ts - eval/a11y.ts - eval/conversion-path.ts
- 02
LLM-as-judge evaluators
Outputs are graded by purpose-built evaluator models on 40+ criteria covering visual hierarchy, accessibility, conversion logic, and brand voice.
Traditional unit tests can't grade if a landing page hero "feels sharp." Our evaluator stack does — and more importantly, it's consistent across runs. Every rebuild ships with its own eval suite, tuned to the client's brand.
eval/checkout.suite.runlog ▸ running eval suite checkout.v4 [PASS] visual-hierarchy 42/42 checks [PASS] a11y-wcag-22-aa 38/38 checks [PASS] conversion-path 17/17 checks [PASS] brand-voice 23/23 checks [RUNNING] perf-lighthouse 4/6 checks [PASS] contract-api-schema 12/12 checks → eval pass rate: 136/136 (100%)→ ready for human review
- 03
Contract tests at every seam
API shapes, data schemas, and UI states are locked in with property-based tests that regenerate automatically when the spec changes.
Humans forget to update tests. Our pipeline doesn't. When a spec changes, the contract tests regenerate to match — and any downstream code that no longer conforms is flagged before merge.
contracts/cart.schema.tstypescript export const CartSchema = z.object({ id: z.string().uuid(), lineItems: z.array(LineItemSchema).min(1), subtotal: z.number().positive(), currency: z.enum(['USD', 'EUR', 'GBP']), customer: CustomerSchema.optional(), }) // auto-regenerated from spec/cart.md on save// last updated: 2026-04-10T14:32:08Z
- 04
Evaluators in production
Validators keep running after deploy. Every real user session is silently graded. Regressions are caught in minutes, not sprints.
Shipping is not the end of validation — it's the beginning. Our production observers run a lightweight version of the eval suite against real traffic, surfacing regressions to your team before they surface to your customers.
obs/eval.streamlog ▸ parity.obs @ prod — listening...14:32:08 session ab3f · checkout.path pass14:32:09 session 7c1e · checkout.path pass14:32:10 session e44a · checkout.path warn lcp 1.34s 14:32:11 session 8b22 · checkout.path pass14:32:12 session fe09 · checkout.path pass# regression alert sent to #eng-oncall (14:32:14)
See the framework on a real rebuild.
Every engagement ships with its own eval suite — tuned to your brand, your schemas, your customers.