background-jobs

background-jobs is a cursor rule for Cursor from levifig/rails-instructions. It costs 0 tokens per session (1,030 once invoked), scanned A, original, MIT.

A set of Rails rules for running work outside the web request, such as sending emails or processing files, using Solid Queue, which stores jobs in a database.

In plain words
What is it for?
Use it when designing background jobs, configuring workers and queues, setting priorities or concurrency limits, and monitoring queued work.
Why use it?
It avoids unnecessary queue services and encourages jobs that can safely retry after failure.

Cursor rule for Cursor

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/levifig/rails-instructions/background-jobs
Clone the repo
git clone --depth 1 https://github.com/levifig/rails-instructions

Made for: Cursor.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for background-jobs

README.md
[![agentmods](https://agentmods.dev/badge/rules/levifig/rails-instructions/background-jobs.svg)](https://agentmods.dev/rules/levifig/rails-instructions/background-jobs)
Your own site
<a href="https://agentmods.dev/rules/levifig/rails-instructions/background-jobs"><img src="https://agentmods.dev/badge/rules/levifig/rails-instructions/background-jobs.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 1,030 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.01030
Opus 5 $0.00000 $0.00515
Sonnet 5 $0.00000 $0.00206
Haiku 4.5 $0.00000 $0.00103

Measured 5d ago against content hash 631bb6dc94a1, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

background-jobs scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.cursor/rules/rails/background-jobs.mdc · 157 lines

How it starts

The opening of the file, as written. The whole thing — 157 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Rails Background Jobs Guide (Solid Queue)

Core Philosophy

  • Use database-backed queuing for simplicity and reliability
  • Avoid external dependencies like Redis when possible
  • Design jobs to be idempotent and retryable
  • Keep background processing simple and focused
  • Leverage Rails' built-in Active Job framework

Solid Queue Principles

  • Database-backed job storage using FOR UPDATE SKIP LOCKED
  • No external dependencies required for basic operation
  • Built-in support for priorities, concurrency limits, and recurring jobs
  • Seamless integration with Active Job interface
  • Production-ready performance with PostgreSQL or MySQL

Configuration Strategy

  • Use separate database for queue in high-volume production environments
  • Configure workers based on job priorities and server resources
  • Set appropriate polling intervals for job urgency
  • Design thread counts based on database connection limits
  • Monitor queue depth and processing times

Queue Organization

  • Design queues based on priority and processing requirements
  • Use semantic queue names that indicate purpose
  • Configure dedicated workers for high-priority queues
  • Set appropriate concurrency limits per queue type
  • Use wildcards sparingly - prefer explicit queue names

Job Design Principles

  • Make all jobs idempotent - safe to run multiple times
  • Keep jobs small and focused on single tasks
  • Pass simple arguments - prefer IDs over objects
  • Design for eventual consistency
  • Handle failures gracefully with proper error reporting

Error Handling Strategy

  • Configure retry behavior based on job importance
  • Use exponential backoff for transient failures
  • Discard jobs that cannot succeed after retries
  • Log errors with sufficient context for debugging
  • Monitor failed job patterns for system issues

Concurrency Controls

  • Use limits_concurrency to prevent resource exhaustion
  • Define concurrency keys based on resource constraints
  • Set appropriate duration for concurrency locks
  • Group related jobs with concurrency controls
  • Monitor for concurrency bottlenecks

Read the full file on GitHub · 157 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 5d ago First seen · 157 lines · 0 tokens per session scan A 631bb6dc94a1

Subscribe to this mod's changes

background-jobs is a cursor rule published in the GitHub repository levifig/rails-instructions (54 stars, last pushed 1y ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,030 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.