ship a release¶

%% A commit's journey from a laptop to production, and back again when the
%% error budget says otherwise. It exercises the attributes the compiler emits
%% and the runtime honours: scenario `speed` and `autoplay`, per-action
%% `color`, and `ease` on the promotion hops.
flowchart LR
  dev[Developer Laptop]
  git[(Git Repository)]
  ci[CI Pipeline]
  reg[(Container Registry)]

  subgraph envs[Kubernetes Environments]
    staging[Staging Cluster]
    prod[Production Cluster]
  end

  dev --> git
  git --> ci
  ci --> reg
  reg --> staging
  staging --> prod
  prod -. rollback .-> reg

scenario "ship a release" { speed: 1.5, autoplay: true }

  step commit "Developer pushes a commit" {
    flow dev -> git { label: "git push", dur: 500ms, color: "#22c55e" }
    highlight git { color: "#22c55e" }
  }

  step build "CI builds and tests the change" {
    flow git -> ci { label: "webhook", dur: 400ms, color: "#22c55e" }
    pulse ci { color: "#22c55e" }
    note ci "unit + integration\n4m 12s"
  }

  step publish "The image lands in the registry" {
    flow ci -> reg { label: "sha-9f2c1a", dur: 600ms, color: "#22c55e" }
    highlight reg { color: "#22c55e" }
  }

  step stage "Promote to staging" {
    flow reg -> staging {
      label: "helm upgrade",
      dur: 700ms,
      color: "#22c55e",
      ease: in-out
    }
    highlight staging { color: "#22c55e" }
  }

  step promote "Promote to production, slowly at first" {
    flow staging -> prod {
      label: "canary 10% then 100%",
      dur: 1100ms,
      color: "#22c55e",
      ease: in-out
    }
    highlight prod { color: "#22c55e" }
  }

  step observe "Error rate climbs past the budget" {
    highlight prod { color: "#ef4444", dur: 700ms }
    note prod "5xx at 4.2%\nSLO burn rate 14x"
  }

  step rollback "Roll back to the last good image" {
    flow prod -> reg {
      label: "rollback to sha-3d81b7",
      dur: 900ms,
      color: "#ef4444",
      ease: out
    }
    highlight reg { color: "#ef4444" }
    dim staging
  }