RZ
Enterprise Architecture

Scalability in Critical Systems

Backend and microservices modernization for high availability under corporate standards (Carga Control / Feeling) — without stopping the business while the engine gets rebuilt.

Domain
Platform / HA
Role
Senior Architect / Full-Stack
Focus
High availability
Standard
Enterprise
Context

High-volume systems where downtime has real cost. Backend diagnosis, phased microservice migration, HA/redundancy and observability without stopping the business.

The challenge

  • 1Sustain peaks without SPOFs.
  • 2Migrate the monolith without a big-bang.
  • 3Meet corporate stability standards.
  • 4Operate on metrics, not intuition.

The approach

01

Performance diagnosis

Bottlenecks and architecture debt prioritized by impact.

02

Progressive migration

Extract critical services with clear API contracts.

03

HA and redundancy

Balancing, replicas, remove single points of failure.

04

Observability

Metrics, logs, traces for evidence-based incident response.

Architecture
Architecture: Scalability in Critical Systems

Clients → load balancer → redundant service cluster, primary + replica DB and cross-cutting observability.

System layers

  1. 01Edge / load balancer
  2. 02Microservice cluster
  3. 03Versioned REST APIs
  4. 04Primary + replica data
  5. 05Docker containers
  6. 06Cross-cutting observability

Applied stack

  • Node.js
  • Microservices
  • REST
  • Docker
  • PostgreSQL
  • Observability

Design decisions

Outcomes

HA
Design without SPOFs
Phased
Migration without business cutover
Ops
Metrics-driven operations

Key points

  • Modernization compatible with operational continuity.
  • Platform engineering focus—not cosmetic rewrite.
  • Ready for corporate stability scrutiny.

Fit / how to hire

Hire this if your backend outgrew its architecture and downtime already costs you real money. Fits as a Staff/Senior Platform role, or as a one-off audit followed by phased implementation.

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