Building a Job Queue System - Part 1: Architecture

Feb 16, 2026

Series Overview

This multi-part series covers building a production-ready job queue system using Redis and Python.

Parts:

Architecture (this post)
Core Queue Implementation
Worker Management
Monitoring and Retries

Architecture Goals

Distributed processing capability
At-least-once delivery guarantee
Priority queues
Job retry with exponential backoff
Dead letter queue for failed jobs

Component Design

1. Job Queue (Redis List)

LPUSH queue:default {job_json}
BRPOP queue:default 0

2. Job Status (Redis Hash)

HSET job:{id} status "pending"
HSET job:{id} payload {json}
HSET job:{id} created_at {timestamp}

3. Priority Queues

Multiple lists with different priorities:

queue:critical
queue:high
queue:default
queue:low

4. Dead Letter Queue

Failed jobs after max retries:

LPUSH queue:dead {job_json}

Data Structures

from dataclasses import dataclass
from enum import Enum

class JobStatus(Enum):
    PENDING = "pending"
    PROCESSING = "processing"
    COMPLETED = "completed"
    FAILED = "failed"
    DEAD = "dead"

@dataclass
class Job:
    id: str
    queue: str
    payload: dict
    status: JobStatus
    attempts: int = 0
    max_attempts: int = 3
    created_at: float = None
    started_at: float = None
    completed_at: float = None

Next Steps

Part 2 will implement the core queue operations: enqueue, dequeue, and status tracking.