CGA
Open to remote roles

Banco Limen

Limen is Latin for threshold: the space between what was and what could be.

Banco Limen is a fictional, composite retail bank. It is a controlled Phase 1 reconstruction of generalized failure patterns from regulated production — not an employer system, source codebase, or data set. The app is the pretext; the infrastructure around it, and the reasoning behind its eventual repair is the point.

Current status: Phase 1 is in progress. The stack deliberately exposes legacy anti-patterns so they can be inspected before later phases address them. This is not a finished cloud-native case study.

The current Phase 1 architecture

All components share one flat Docker bridge network. That lack of segmentation is intentional: it is part of the system being examined.

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                                Banco Limen / Phase 1

  Client
    │ :5001
    ▼
  Flask application (:5000) ───────────────► PostgreSQL 12
    │  exposes /metrics                         │
    │                                            │
    ├──── Prometheus scrapes ────────────────────┘
    │          │
    │          ├────► Grafana reads metrics
    │          ├────► node-exporter (running)
    │          └────► postgres-exporter + legacy VMs (configured, absent)
    │
    ├────► Elasticsearch ◄──── Kibana
    │       (no retention)      (stale dashboards)
    │
    └────► Jaeger
            installed, but the application emits no spans

  All services: one flat limen-network bridge

The architecture is intentionally inconsistent: Prometheus, ELK, and Jaeger coexist without useful correlation; the database has no replica; several scrape targets do not exist; and a compromised service can reach every component on the flat network.

What to inspect

  1. Problem inventory — 38 documented failure patterns.
  2. Phase 1 design — the current stack and the anti-patterns it reproduces.
  3. Architecture Decision Records — why each deliberate decision exists in Phase 1.
  4. The Limen repository — source, current roadmap, and the preserved Phase 1 baseline.