BloomSpec
StacksShared across all subject areas

Modern production

What you would build today for a real multi-tenant close platform at enterprise scale.

Context

AWS-centred: Aurora Postgres, ECS, S3 with object lock, Temporal for durable workflow, SageMaker for per-tenant models, an LLM gateway with regional routing. Assumes SOC 2, multi-region residency, and customers whose auditors will examine the platform's own controls.

Stack choices44
Stack fit96
  • Exact decimal arithmetic end to end — database column, ORM mapping, API serialisation and client. Floating point anywhere in the chain is disqualifying.
  • Certified periods must be immutable at the storage layer, not by application convention. No in-place update, no soft delete, and reopening must itself be an audited event.
  • Append-only, tamper-evident audit log with retention measured in years, held separately from application logging.
  • Authorisation must evaluate rules against the record's own history, not only the user's role. Plain RBAC is structurally insufficient.
  • Exchange rates must be effective-dated and keyed by convention. There is no single current rate.
  • Accounting date and system timestamp must be separate fields. The period an entry belongs to cannot be derived from when it was recorded.
  • Tolerance models must be trained per tenant. One tenant's variance distribution cannot inform another's.
  • Risk scoring models must be per tenant, with model artefacts and training data isolated to the same boundary as the tenant's transactional data.
  • Document-reading model calls must route to an endpoint in the tenant's permitted jurisdiction under a contractual no-retention guarantee.
  • Alerting must include domain-correctness metrics — auto-match rate, exception volume, unexplained residuals — not only infrastructure health.
  • Machine-generated narrative must carry provenance metadata and require human approval before it becomes part of the record.
  • Approval workflows must be durable and resumable across days, surviving restarts, deployments and approver absence without losing state.
  • and 84 more