go-concurrency-patterns

Overview of go-concurrency-patterns skill

What the go-concurrency-patterns skill does

The go-concurrency-patterns skill helps an agent produce and explain idiomatic Go concurrency designs: goroutines, channels, select, sync primitives, and context-driven cancellation. It is most useful when you need working patterns for worker pools, pipelines, fan-out/fan-in, graceful shutdown, or race-condition cleanup rather than generic Go advice.

Who should install it

Best fit readers are backend engineers, Go learners moving into production code, and AI-assisted developers who want better concurrency scaffolding for services, jobs, and event-processing systems. If your work involves request lifecycles, background workers, parallel I/O, or shutdown safety, this skill is relevant.

The real job-to-be-done

Users typically want one of four outcomes: choose the right concurrency primitive, generate a safe starting implementation, add cancellation and shutdown behavior, or debug why goroutines block, leak, or race. The go-concurrency-patterns skill is valuable because it focuses on these practical decisions instead of treating concurrency as syntax only.

What differentiates this skill from a generic Go prompt

A normal prompt may produce concurrent code that runs but ignores cancellation, backpressure, channel ownership, or shutdown coordination. The go-concurrency-patterns skill is centered on production patterns and the Go concurrency mantra: communicate through channels where appropriate, and use synchronization primitives deliberately when shared state is unavoidable.

What to know before adopting

This is a text-only skill with guidance and examples in SKILL.md; there are no helper scripts or extra reference files. That makes adoption easy, but it also means output quality depends heavily on how clearly you describe your workload, error handling, throughput goals, and shutdown requirements.

How to Use go-concurrency-patterns skill

How to install go-concurrency-patterns

Use your standard skills workflow to add the skill from the repository:

npx skills add https://github.com/wshobson/agents --skill go-concurrency-patterns

If your environment already syncs skills from the wshobson/agents repository, make sure the plugins/systems-programming/skills/go-concurrency-patterns path is available locally.

What to read first

Read SKILL.md first and in this order:

1. When to Use This Skill
2. Core Concepts
3. Quick Start
4. Any sections covering worker pools, pipelines, cancellation, or race-condition handling

Because the repository only exposes SKILL.md for this skill, there is little hidden context. That is good for speed: you can assess the skill quickly without hunting through support files.

What inputs the skill needs to work well

The go-concurrency-patterns skill performs best when you provide:

• the type of workload: CPU-bound, I/O-bound, streaming, batch, or request-scoped
• desired pattern: worker pool, fan-out/fan-in, pipeline, pub/sub-like channel flow, shared-state coordination
• lifecycle rules: timeout, cancellation, graceful shutdown, retry, drain behavior
• error policy: fail fast, aggregate errors, partial success, best effort
• limits: worker count, queue size, memory pressure, ordering requirements
• current symptoms if debugging: deadlock, goroutine leak, blocked channel send, race detector output

Without these inputs, the agent may choose a valid pattern that is wrong for your throughput or shutdown needs.

Turn a rough goal into a strong prompt

Weak prompt:

• "Help me use concurrency in Go."

Strong prompt:

• "Use the go-concurrency-patterns skill to design a worker pool for a Go backend service that fetches 5,000 URLs with max concurrency 20, request timeout 2s, context cancellation on shutdown, bounded queueing, and error aggregation. Show the package layout, core types, and explain why channels versus sync.Mutex are used."

The stronger version works because it supplies scale, concurrency limits, timeout policy, and the expected architectural output.

Prompt template for go-concurrency-patterns usage

Use a structure like this:

• Goal: what the system must accomplish
• Workload shape: batch, stream, RPC handler, background daemon
• Concurrency pattern you suspect or want evaluated
• Constraints: throughput, ordering, memory, timeouts
• Failure modes to avoid
• Output format: explanation, code, refactor, review checklist, test plan

Example:

• "Use the go-concurrency-patterns skill for Backend Development. I have an event ingestion service in Go. Recommend whether to use channels, a worker pool, or mutex-protected shared state. Include shutdown handling with context.Context, note race risks, and provide a minimal implementation plus tests."

Common usage flows

Typical go-concurrency-patterns usage falls into three flows:

1. New design

   • ask for a pattern recommendation
   • request a minimal implementation
   • refine for cancellation, backpressure, and metrics

2. Code review

   • paste existing Go code
   • ask the agent to identify misuse of channels, WaitGroup, Mutex, or context
   • request a safer rewrite

3. Debugging

   • provide symptoms and stack traces or race detector output
   • ask for likely root causes
   • request instrumentation and a fix strategy

Best-fit patterns the skill can help with

The go-concurrency-patterns skill is especially useful for:

• worker pools
• fan-out/fan-in processing
• staged pipelines
• request-scoped parallelism
• cancellation propagation with context.Context
• graceful shutdown and draining
• replacing unsafe shared state with clearer coordination

These are the areas where a specialized skill usually beats an ordinary prompt.

Where this skill is less helpful

It is a weaker fit when your problem is mainly:

• low-level lock-free algorithm design
• runtime scheduler internals
• distributed systems coordination across services
• framework-specific integration details not described in the skill
• heavy performance tuning that needs benchmarks and profiling data first

In those cases, use the skill for initial structure, then validate with profiling, benchmarks, and real code review.

Practical repository-reading path

Because the repository surface is small, a sensible reading path is:

1. skim the description and use cases
2. review the primitive table
3. inspect the quick-start example for context, channels, and WaitGroup
4. then ask the agent for a pattern matched to your exact backend workload

This saves time versus reading every example line before you know whether you need a pipeline, worker pool, or shared-state design.

Tips that materially improve output quality

Ask the agent to state:

• who owns each channel
• who closes each channel
• where cancellation enters the system
• how goroutines terminate
• what happens when consumers are slower than producers
• whether result ordering matters

These details prevent many bad AI-generated concurrency examples. If the answer does not make ownership and shutdown explicit, ask for a revision.

go-concurrency-patterns skill FAQ

Is go-concurrency-patterns good for beginners?

Yes, if you already know basic Go syntax. The skill is practical rather than academic: it teaches primitives in the context of real backend tasks. Absolute beginners may still need a separate introduction to goroutines, channels, and context.

Is go-concurrency-patterns only for Backend Development?

No, but go-concurrency-patterns for Backend Development is the strongest fit. Backend services often need bounded concurrency, graceful shutdown, cancellation, and error handling across many tasks, which aligns closely with the skill.

How is this different from asking for Go code directly?

A direct prompt often returns code that compiles but misses lifecycle concerns. The go-concurrency-patterns skill is more likely to surface channel coordination, context propagation, waiting semantics, and shutdown behavior—the parts that usually fail in production.

Does the skill include install scripts or runnable tooling?

No. The repository evidence shows only SKILL.md for this skill. There are no bundled scripts, resources, or rules to automate validation, so you should expect guidance and examples rather than executable helpers.

When should I not use go-concurrency-patterns?

Skip it if your need is mostly framework glue, database tuning, or distributed workflow orchestration across multiple services. Also avoid relying on it alone for highly optimized concurrency code without benchmark-driven validation.

Can it help debug race conditions and goroutine leaks?

Yes. That is one of the clearest use cases. It is especially useful if you provide a reduced code sample, go test -race output, blocked stack traces, or a description of when goroutines fail to exit.

How to Improve go-concurrency-patterns skill

Give the skill architectural context, not just code

The best way to improve go-concurrency-patterns output is to explain the system boundary: HTTP handler, background worker, CLI batch job, or stream processor. Concurrency choices differ a lot by lifecycle and cancellation model.

Be explicit about throughput and limits

If you want a worker pool, say how many workers, expected task count, latency target, and whether queue growth is acceptable. This helps the skill choose bounded channels, backpressure, or direct handoff instead of vague concurrency.

Ask for ownership and shutdown rules

A strong follow-up prompt is:

• "Revise this using the go-concurrency-patterns skill and annotate channel ownership, close points, cancellation flow, and goroutine termination conditions."

That single request often upgrades output from demo code to something much closer to production-safe.

Request comparison, not just one answer

When unsure, ask for tradeoffs:

• channels vs sync.Mutex
• worker pool vs per-task goroutine spawning
• buffered vs unbuffered channels
• shared error channel vs structured aggregation

This is one of the best ways to use the go-concurrency-patterns guide for decision support instead of code generation alone.

Validate generated code with Go tooling

After using the go-concurrency-patterns skill, run:

• go test
• go test -race
• benchmarks if throughput matters
• shutdown/cancellation tests if the code is long-lived

The skill can improve design quality, but race detection and benchmark evidence should decide final adoption.

Common failure modes to correct early

Watch for these issues in first-pass output:

• channels closed by the wrong goroutine
• missing cancel() or ignored ctx.Done()
• WaitGroup increments inside goroutines
• unbounded goroutine creation
• deadlocks from sends with no active receiver
• mutex use where channel-based coordination would be clearer, or the reverse

These are realistic places where go-concurrency-patterns usage should lead to targeted revisions.

Improve prompts with realistic examples

Instead of:

• "make this concurrent"

Use:

• "Use the go-concurrency-patterns skill to refactor this sequential file processing loop into a bounded worker pool with max concurrency 8, ordered final output, cancellation on first fatal error, and a clean shutdown path."

Specificity improves both the selected pattern and the code shape.

Iterate after the first answer

A good second-round prompt is:

• "Now review your own solution for race risks, goroutine leaks, blocked sends, and shutdown edge cases. Show the revised version and explain each change."

For this skill, self-critique is especially valuable because concurrency bugs often hide in edge conditions, not the happy path.