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Roles and stylesheet

Classes are roles. accent, ok, warn, danger, muted, the dashed cluster group and the edges failure and async take their tones from the theme; queue and senders come from the site stylesheet docs/src/styles/diagrams.css, which pages link only as compiled CSS. The inline diagram follows the theme switch in the header; the two images are standalone SVGs with the light and dark themes baked in, so they keep their colours in any host.

Source: bench/fixtures/roles/, shared with the stylesheet parity gate.

Two tier roles

Section titled “Two tier roles”
Push scheduler with roles Flowchart, left to right. 13 nodes, 15 edges. cron trigger every minute idempotent run key → lease one run per window 90 s TTL durable workflow: lease one run per window 90 s TTL → due set scan schedules next_at ≤ now durable workflow: due set scan schedules next_at ≤ now → budget 250 push slots per-tenant caps durable workflow: budget 250 push slots per-tenant caps → enqueue batches of 100 dedupe by job id durable workflow: enqueue batches of 100 dedupe by job id → wait sleep until acked or 30 s timeout; → push queue at-least-once visibility 60 s [batch] durable workflow: wait sleep until acked or 30 s timeout → finalize record outcomes advance next_at durable workflow: finalize record outcomes advance next_at → release drop the lease durable workflow: release drop the lease push queue at-least-once visibility 60 s → sender A APNs; → sender B FCM; → sender C web push; → dead letters after 5 attempts kept 14 days [max retries] consumers: sender A APNs → wait sleep until acked or 30 s timeout [ack] consumers: sender B FCM → wait sleep until acked or 30 s timeout [ack] consumers: sender C web push → wait sleep until acked or 30 s timeout [ack] durable workflow leaseone run per window90 s TTL due setscan schedulesnext_at ≤ now budget250 push slotsper-tenant caps enqueuebatches of 100dedupe by job id waitsleep until ackedor 30 s timeout finalizerecord outcomesadvance next_at releasedrop the lease consumers sender AAPNs sender BFCM sender Cweb push batch ack ack ack max retries cron triggerevery minuteidempotent run key push queueat-least-oncevisibility 60 s dead lettersafter 5 attemptskept 14 days
Push scheduler with roles
Diagram source
flowchart LR
  accTitle: Push scheduler with roles
  cron["**cron trigger**<br/>every minute<br/>idempotent run key"]
  subgraph wf["durable workflow"]
    lease["**lease**<br/>one run per window<br/>90 s TTL"]
    due["**due set**<br/>scan schedules<br/>next_at ≤ now"]
    budget["**budget**<br/>250 push slots<br/>per-tenant caps"]
    enqueue["**enqueue**<br/>batches of 100<br/>dedupe by job id"]
    wait["**wait**<br/>sleep until acked<br/>or 30 s timeout"]
    finalize["**finalize**<br/>record outcomes<br/>advance next_at"]
    release["**release**<br/>drop the lease"]
    lease --> due --> budget --> enqueue --> wait --> finalize --> release
  end
  q[("**push queue**<br/>at-least-once<br/>visibility 60 s")]
  subgraph consumers["consumers"]
    c1["**sender A**<br/>APNs"]
    c2["**sender B**<br/>FCM"]
    c3["**sender C**<br/>web push"]
  end
  dlq[("**dead letters**<br/>after 5 attempts<br/>kept 14 days")]
  cron --> lease
  enqueue e1@-->|batch| q
  q --> c1 & c2 & c3
  c1 & c2 & c3 -.->|ack| wait
  q e2@-->|max retries| dlq
  class cron accent
  class lease,release muted
  class budget warn
  class finalize ok
  class dlq danger
  class e1 async
  class e2 failure
  class wf group
  class q queue
  class consumers senders

Two tier roles, standalone with the light theme baked in

Two tier roles, standalone with the dark theme baked in