Interactive bunqueue Simulator: Try the Bun Job Queue in Your Browser

Interactive Simulator

Experience bunqueue’s features directly in your browser. This simulator implements the core queue functionality including:

• Sharding - See how jobs are distributed across shards using FNV-1a hash
• Priority Queue - Jobs with higher priority are processed first
• Delayed Jobs - Schedule jobs to run after a delay
• Workers - Start concurrent workers to process jobs
• DLQ (Dead Letter Queue) - Failed jobs after max retries go to DLQ
• Queue Control - Pause, resume, and drain queues

bunqueue Interactive Simulator

Real-time visualization of queue operations, sharding, and job lifecycle

8Shards

0Pushed

0Processed

0Failed

0Workers

0Queues

Controls

Queue Name

Job Name

Job Data (JSON){"to": "user@example.com"}

Priority

Delay (ms)

Push JobPush 10 Jobs

Bulk Count10

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Worker Concurrency3

Start Worker

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PauseResumeDrain

Retry DLQ

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Failure Rate: 10%

Reset Simulator

Shards (0)

Waiting Delayed Active Completed Failed

Queues

No queues yet. Push some jobs!

Workers

No workers running. Start one!

Events (Last 50)

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How It Works

Sharding

The simulator uses the same FNV-1a hash algorithm as bunqueue to distribute queues across shards:

shardIndex = fnv1aHash(queueName) & SHARD_MASK

Each queue maps to exactly one shard, and all jobs in that queue share the same shard.

Job Lifecycle

PUSH → waiting/delayed → PULL → active → ACK/FAIL → completed/retry/DLQ

1. Push - Job enters the queue in waiting state (or delayed if delay > 0)
2. Pull - Worker pulls job, state becomes active
3. Ack - Job completed successfully → completed
4. Fail - Job failed, will retry or move to DLQ

Try These Scenarios

1. High Throughput: Push 100 jobs with a running worker
2. Priority Processing: Push jobs with different priorities (higher = sooner)
3. Delayed Jobs: Add jobs with 5000ms delay, watch them become ready
4. Failure Handling: Increase failure rate, observe retries and DLQ
5. Queue Control: Pause a queue, push jobs, resume and watch processing

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Differences from Real bunqueue

Feature	Simulator	Real bunqueue
Storage	In-memory	SQLite
Shards	8 (configurable)	Auto-detected from CPU
Workers	Simulated delays	Real processing
Persistence	None (page refresh resets)	Full durability
TCP Server	N/A	Full protocol

The simulator is designed for learning and demonstration purposes. For production workloads, use the real bunqueue server.