Golang Uber Dig

What it does

When your agent uses it

• Tasks that involve Design patterns

Example prompts

• “/golang-uber-dig”

Requirements

• Compatibility (from SKILL.md): Designed for Claude Code, Codex or similar harness, and for projects using Golang.
• Pre-approved tools (allowed-tools): Read, Edit, Write, Glob, Grep, Bash(go:*), Bash(golangci-lint:*), Bash(git:*), Agent, WebFetch, mcp__context7__resolve-library-id, mcp__context7__query-docs, Bash(godig:*), Bash(gopls:*), LSP, mcp__gopls__*

Workflow steps

6 steps, taken from the first numbered list in SKILL.md.

1. 1Keep the container at the composition root — never pass *dig.Container as a parameter; treat it like a plumbing detail of main()…
2. 2Depend on interfaces, not concrete types — lets you swap implementations in tests without touching production code, and lets you use…
3. 3Prefer parameter objects (dig.In structs) once a constructor has 4+ dependencies — call sites stay readable and adding a new dependency is…
4. 4Group registration by module (one file per module that calls c.Provide for its types) — review and refactoring become a per-module…
5. 5Validate the graph eagerly in tests — call c.Invoke against the composition root in CI to surface missing providers at boot time, not at…
6. 6Return errors from constructors instead of panicking — dig wraps them with the dependency path, which makes the failure point obvious.

What it can do on your machine

Read from SKILL.md and the folder at commit 8876467. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves these tools, so the agent can use them without asking each time:

  • Read
  • Edit
  • Write
  • Glob
  • Grep
  • Bash(go:*)
  • Bash(golangci-lint:*)
  • Bash(git:*)
  • Agent
  • WebFetch

  …and 6 more on the same allowed-tools line.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  Shell commands in SKILL.md call:

  • go

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Links to these hosts (documentation or services it may open):

  • github.com
  • pkg.go.dev

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

• Compatibility

  Designed for Claude Code, Codex or similar harness, and for projects using Golang.

  From compatibility in the SKILL.md frontmatter.

Context cost

Golang Uber Dig loads about 2.6k tokens when it runs, and up to ~6.4k if it reads all its reference files. Until then it costs about 67 tokens; SKILL.md has 936 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~67

When it runs · the whole SKILL.md, loaded when a task matches

~2.6k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~6.4k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from context-labs/whip at commit 8876467, republished under its MIT licence (© context-labs). 936 words, ~2,591 tokens.

name

golang-uber-dig

description

Dependency injection in Golang using uber-go/dig — reflection container, Provide/Invoke, dig.In/dig.Out objects, named values, value groups, optional deps, scopes. Apply when using/adopting dig or on go.uber.org/dig imports. Lifecycle → golang-uber-fx.

allowed-tools

Read, Edit, Write, Glob, Grep, Bash(go:*), Bash(golangci-lint:*), Bash(git:*), Agent, WebFetch, mcp__context7__resolve-library-id, mcp__context7__query-docs, Bash(godig:*), Bash(gopls:*), LSP, mcp__gopls__*

compatibility

Designed for Claude Code, Codex or similar harness, and for projects using Golang.

user-invocable

true

license

MIT

metadata.author

samber

metadata.version

1.2.0

paths

**/*.go

go get go.uber.org/dig

import "go.uber.org/dig"

c := dig.New()

// Register a constructor — lazy, only runs when its output is needed
err := c.Provide(func(cfg *Config) (*sql.DB, error) {
    return sql.Open("postgres", cfg.DSN)
})

// Pull a service out of the container by asking for it as a function parameter
err = c.Invoke(func(db *sql.DB) error {
    return db.Ping()
})

type HandlerParams struct {
    dig.In

    Logger *zap.Logger
    DB     *sql.DB
    Cache  *redis.Client `optional:"true"`           // zero value if not provided
    DBRO   *sql.DB       `name:"readonly"`           // named dependency
    Routes []http.Handler `group:"routes"`           // value group
}

func NewHandler(p HandlerParams) *Handler { /* ... */ }

type ConnResult struct {
    dig.Out

    ReadWrite *sql.DB `name:"primary"`
    ReadOnly  *sql.DB `name:"readonly"`
}

func NewConnections(cfg *Config) (ConnResult, error) { /* ... */ }

c.Provide(NewPrimaryDB,  dig.Name("primary"))
c.Provide(NewReadOnlyDB, dig.Name("readonly"))

type RouteResult struct {
    dig.Out
    Handler http.Handler `group:"routes"`
}

func NewUserHandler(db *sql.DB) RouteResult { /* ... */ }
func NewPostHandler(db *sql.DB) RouteResult { /* ... */ }

type ServerParams struct {
    dig.In
    Routes []http.Handler `group:"routes"`
}

c.Provide(NewPostgresDB, dig.As(new(Database), new(io.Closer)))
// Consumers ask for Database or io.Closer; *PostgresDB stays hidden.

func main() {
    c := dig.New()

    must(c.Provide(NewConfig))
    must(c.Provide(NewLogger))
    must(c.Provide(NewDatabase))
    must(c.Provide(NewServer))

    err := c.Invoke(func(srv *http.Server) error {
        return srv.ListenAndServe()
    })
    if err != nil {
        log.Fatal(err)
    }
}

func must(err error) { if err != nil { panic(err) } }

© context-labs, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 4 other files (references) in .agents/skills/golang-uber-dig of context-labs/whip.

• SKILL.md
• evals/evals.json
• references/advanced.md
• references/recipes.md
• references/testing.md

Open the folder on GitHubat commit 8876467

Used in 1 other repository

We found 1 copy of this SKILL.md (exact, near-identical or edited) in other folders, from 1 other GitHub owner. This page covers the copy in context-labs/whip, which our catalogue first saw on October 7, 2026.

• samber/cc-skills-golangskills/golang-uber-dig