System Architecture

Serverless, audit-first design on AWS — DynamoDB is the system of record.

Request path

Next.js

App Router / RSC

API Routes

Route Handlers

DynamoDB

EvidenceOps

Audit event pipeline (roadmap)

Audit Events

DynamoDB (live)

EventBridge

planned

Lambda

planned

S3

planned

Today, every reviewer decision is written append-only to DynamoDB with a versioned provenance chain (live). The fan-out path — DynamoDB Streams → EventBridge → a Lambda that assembles immutable audit packs into S3 — is the planned next step; audit-pack metadata and lifecycle status are already modeled in the table.

DynamoDB single-table access patterns

EvidenceOps · us-east-1
EntityOperationKey condition
ProjectGetItemPK=PROJECT#<id>, SK=META
CohortQueryPK=PROJECT#<id>, begins_with(SK, COHORT#)
SampleQueryPK=COHORT#<id>, begins_with(SK, SAMPLE#)
Sample (by decision)Query GSI1GSI1PK=COHORT#<id>, GSI1SK=DECISION#<state>
PGx RunGetItemPK=SAMPLE#<id>, SK=RUN#latest
Audit EventQueryPK=AUDIT#<entityId>, begins_with(SK, EVENT#)
Audit PackGetItemPK=PACK#<id>, SK=META

Version manifest

PGx Engine

v1.3.2

Evidence Base

2026.06

Region

us-east-1