---
title: Configuration
description: Functional options, the Config struct, and how to customize Dispatch behavior.
---

Dispatch uses functional options for wiring dependencies and a `Config` struct for tuning runtime behavior.

## Dispatcher options

The `Dispatcher` is configured with functional options passed to `dispatch.New()`:

```go
d, err := dispatch.New(
    dispatch.WithStore(postgresStore),
    dispatch.WithLogger(slog.Default()),
    dispatch.WithConcurrency(20),
    dispatch.WithQueues([]string{"default", "critical", "bulk"}),
)
```

### Available options

| Option | Purpose | Default |
|--------|---------|---------|
| `WithStore(s)` | Set the persistence backend (required) | — |
| `WithLogger(l)` | Set the structured logger | `slog.Default()` |
| `WithConcurrency(n)` | Max concurrent jobs processed | `10` |
| `WithQueues(q)` | Queues to poll | `["default"]` |

## Config struct

```go
type Config struct {
    Concurrency       int           // default: 10
    Queues            []string      // default: ["default"]
    PollInterval      time.Duration // default: 1s
    ShutdownTimeout   time.Duration // default: 30s
    HeartbeatInterval time.Duration // default: 10s
    StaleJobThreshold time.Duration // default: 30s
}
```

`DefaultConfig()` returns a Config with these defaults.

## Engine options

Additional options are passed to `engine.Build()`:

```go
eng := engine.Build(d,
    engine.WithExtension(metricsExt),
    engine.WithMiddleware(middleware.Logging(logger)),
    engine.WithBackoff(backoff.Exponential(
        backoff.WithBase(5*time.Second),
        backoff.WithMax(2*time.Hour),
    )),
    engine.WithQueueConfig(queue.Config{
        Name:           "critical",
        MaxConcurrency: 20,
        RateLimit:      50,
    }),
    engine.WithTracerProvider(tracerProvider),
    engine.WithMetricFactory(metricFactory),
)
```

## Forge extension config

When using the Forge framework integration:

```go
ext := extension.New(
    extension.WithStore(pgStore),
    extension.WithConcurrency(20),
    extension.WithQueues([]string{"default", "bulk"}),
    extension.WithBasePath("/api/dispatch"),
    extension.WithDisableRoutes(),
    extension.WithDisableMigrate(),
)
```

| Option | Purpose | Default |
|--------|---------|---------|
| `WithStore(s)` | Persistence backend | — |
| `WithConcurrency(n)` | Max concurrent jobs | `10` |
| `WithQueues(q)` | Queues to poll | `["default"]` |
| `WithBasePath(p)` | HTTP API prefix | `"/api/dispatch"` |
| `WithDisableRoutes()` | Skip HTTP route registration | `false` |
| `WithDisableMigrate()` | Skip auto-migration at startup | `false` |

## Required options

The only required option is `WithStore()`. Without a store, `dispatch.New()` returns `ErrNoStore`.