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Front End Progressive Deployment Service

A safe, automated rollout system for Front End applications with metric-driven gates and automatic rollback.

Company: Credit Karma

platform-engineeringdevopsnodejsreliability
Summary
A deployment safety layer that automates progressive rollouts, validates health with real metrics, and rolls back instantly when signals degrade—bringing backend-grade practices to frontend releases.

A progressive rollout service designed to ship frontend changes with confidence. The system automates traffic ramp-ups, validates health via real metrics, and rolls back instantly when signals degrade. It brings backend-grade deployment safety to web platforms.

This project was based on the concepts for Argo Rollouts, and closely mirrors their implementation; but was custom built to for Credit Karma's front end deployment system.

Context

Large product surfaces and multi-team codebases make risk management critical. Traditional frontend releases often rely on manual checks and qualitative judgment, which can be inconsistent and slow. This project established a standardized, automated path to production.

What I built

  • A standalone service coordinating progressive rollouts using a declarative rollout.yml per project, mirroring Argo Rollouts standards
  • A state machine and worker queue that executes rollout steps and evaluates health checks
  • Pluggable "weight providers" to integrate with existing deploy infrastructure, which is not Kubernetes-based
  • Health analysis powered by queryable telemetry (e.g., error rates, latency, conversion proxies)
  • First-class observability and audit trails for every rollout step

How it works

  1. Teams define rollout plans in code: traffic weights, pauses, and analysis checks
  2. The service applies each step, shifting traffic gradually to the canary version
  3. For every step, it runs metric queries; on failure, it halts and rolls back automatically
  4. On success, it promotes to 100% and records the outcome
Rendering diagram…
Progressive rollout with automatic health checks and rollback

Outcomes for clients

  • Reduced member impact via automated, immediate rollbacks
  • Faster, safer releases with consistent, repeatable practices
  • Clear accountability with dashboards and auditable histories
  • A reusable pattern that scales across products and organizations

Tech notes

  • Service runtime in Node.js with durable state and background workers
  • Configuration-as-code via YAML to keep rollout logic versioned with the project
  • Extensible adapters to connect to your deploy targets and telemetry stack

Engagement model

I help teams adopt progressive delivery pragmatically: design the minimal viable metrics, wire telemetry, and layer safeguards that match the organization’s maturity. The result is a measurable drop in release risk without slowing velocity.