# Creating a Store

A store is how ArchitectureKit reads from and writes to EventSourcingDB. The functions that read or write events, such as `Execute`, `Load`, `Read`, and those that run projections, take it as an argument.

Import the package, create an EventSourcingDB client, and create a store by providing the client and the source to use for all events you write:

```go
import (
  "net/url"

  "github.com/thenativeweb/architecturekit-golang/architecturekit"
  "github.com/thenativeweb/eventsourcingdb-client-golang/eventsourcingdb"
)

// ...

baseURL, err := url.Parse("http://localhost:3000")
if err != nil {
  // ...
}

apiToken := "secret"

client, err := eventsourcingdb.NewClient(baseURL, apiToken)
if err != nil {
  // ...
}

store := architecturekit.NewStore(client, "https://library.eventsourcingdb.io")
```

The `NewStore` function returns a `*Store`, which reads and writes the events of all commands. For details on the client, see the **[client SDK for Go](/docs/eventsourcingdb/sdks/go)**.

*Note that calling `NewStore` with `nil` as the client, or as one of the options, panics.*

## Choosing the Source

The second argument of `NewStore` is the source for all events you write. Every event in EventSourcingDB has one, and it identifies the system that produced the event, such as `https://library.eventsourcingdb.io`. It must be a URI reference, such as a URL or a tag URI, and it does not affect how events are processed (see **[Sources](/docs/eventsourcingdb/sources)**).

## Configuring the Store

`NewStore` takes options after the source. They configure the new store before it exists, so they can not change a store that is in use. There are these options:

- `WithConflictRetries` has `Execute` decide again on a conflict, up to the given number of times (see **[Guarding Against Concurrent Changes](/docs/architecturekit/using-preconditions#guarding-against-concurrent-changes)**).
- `WithStateCache` keeps the states of the most recently used subjects in memory (see **[Caching States](/docs/architecturekit/caching-states)**).
- `WithReconnectDelays` sets how long running projections wait before they read again after reading failed or the stream ended (see **[Running Projections](/docs/architecturekit/projections#running-projections)**).
- `WithReconnectObserver` calls a function every time a running projection is about to wait before reading again, for example to log it (see **[Running Projections](/docs/architecturekit/projections#running-projections)**).
- `WithSignatureVerification` checks the signature of every event the store reads, besides its hash (see **[Verifying Events](/docs/architecturekit/verifying-events)**).
- `WithoutHashVerification` turns off checking the hash of every event the store reads, which the store does unless told otherwise (see **[Verifying Events](/docs/architecturekit/verifying-events)**).

*Note that `WithoutHashVerification` can not be combined with `WithSignatureVerification`, since checking a signature includes checking the hash, so `NewStore` panics if it gets both.*