golang

A set of Go programming rules based on the Uber Go Style Guide. Go is a programming language designed for building reliable software with simple, compiled code.

In plain words
What is it for?
Use it when creating or reviewing Go projects. It covers package layout, internal code, interfaces, method receivers, repositories, and test file organization.
Why use it?
It gives a consistent way to organize Go projects and design packages, interfaces, methods, and tests, reducing confusing or hard-to-maintain code.

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/mitas/cursor-rules/golang
Clone the repo
git clone --depth 1 https://github.com/mitas/cursor-rules

Made for: Cursor.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 2,532 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 $0.02532
Opus 5 $0.00000 $0.01266
Sonnet 5 $0.00000 $0.00506
Haiku 4.5 $0.00000 $0.00253

Measured yesterday against content hash 2efb57364b30, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

golang 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 yesterday.

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/golang.mdc · 298 lines

How it starts

The opening of the file, as written. The whole thing — 298 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Go (Golang) Coding Standards

Project Structure

Note: For comprehensive project structure guidelines, refer to golang-project-structure.mdc

  • Organize code into logical packages
  • Package names should be lowercase, short, and not plural
  • Follow the standard Go project layout (cmd/, pkg/, internal/)
  • Use /internal for code not meant to be imported by other projects
  • Separate models, services, and controllers
  • Group related functionality in the same package
  • Implement repository pattern for data access
  • Organize tests in the same package as production code with _test.go suffix

Interfaces and Types

Interface Design

  • No pointers to interfaces: pass interfaces as values
  • Verify interface compliance at compile time: var _ Interface = (*Implementation)(nil)
  • Keep interfaces small and focused (ideally 1-3 methods)
  • Use interfaces at package boundaries for better testing
  • Design interfaces for consumers, not implementations
  • Don't export interfaces for concrete types with a single implementation

Method Receivers

  • Use value receivers for methods that don't modify the receiver
  • Use pointer receivers for methods that modify the receiver
  • Be consistent with receiver types for the same struct
  • Methods with value receivers can be called on pointers as well as values
  • Methods with pointer receivers can only be called on pointers or addressable values
  • If any method requires a pointer receiver, use pointer receivers for all methods

Type Assertions

  • Always use the "comma ok" idiom: val, ok := x.(T)
  • Don't use type assertions without checking the result
  • Use type switches for multiple potential types
  • Consider using the errors.As function for error type checking

Error Handling

Error Creation

  • Return errors instead of using panic
  • Create specialized error types for specific error cases
  • Implement Error() string method for custom error types
  • Use errors.New for simple errors
  • Add context when wrapping errors: fmt.Errorf("doing X: %w", err)
  • Use %w verb for error wrapping to preserve the original error

Read the full file on GitHub · 298 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. yesterday First seen · 298 lines · 2,532 tokens per session scan A 2efb57364b30

Subscribe to this mod's changes

golang is a cursor rule published in the GitHub repository mitas/cursor-rules (2 stars, last pushed 1y ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 2,532 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 2026-08-31.