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quiz vs the machine

Platinum1720

System Design

Progressive Delivery

Rolling out change in controlled stages, each gated by health, all the way to everyone.

6 min read · advanced · beat Platinum to climb

Beyond a single canary

Progressive delivery is the discipline of releasing change in widening stages, each one gated by health checks before the next begins. It generalizes the canary into a full pipeline: a tiny first wave, then larger ones, with an automatic stop and roll back if any wave looks unhealthy.

The stages

  • Wave one exposes the change to a small population such as internal users.
  • Wave two widens to a single region or a few percent of traffic.
  • Later waves ramp toward one hundred percent, pausing at each gate.

Between waves a bake time lets slow signals like memory leaks or error spikes surface before more users are exposed.

Why staging matters

Each gate is a chance to catch a problem while its blast radius is still small. Combined with feature flags and canary analysis, progressive delivery makes a risky change into a series of small, reversible steps.

Key idea

Progressive delivery ramps a change through health gated waves so problems are caught while the blast radius is still small.

Check yourself

Answer to earn rating on the learn ladder.

1. How does progressive delivery extend a canary?

2. What is the purpose of bake time between waves?