---
title: Identity (TypeID)
description: How Chronicle uses prefix-qualified, globally unique identifiers for every entity.
---

Every entity in Chronicle has a TypeID. TypeIDs are globally unique, sortable, URL-safe identifiers built on UUIDv7 with a human-readable prefix that tells you what kind of entity you're looking at.

A TypeID looks like this:

```
audit_01h455vb4pex5vsknk084sn02q
```

The `audit` prefix identifies this as an audit event. The suffix is a base32-encoded UUIDv7 that encodes creation time, so IDs sort chronologically.

## The `id` package

The `id` package wraps the [TypeID Go library](https://github.com/jetify-com/typeid-go) (v2) with a single `ID` struct. All entity types share the same struct -- the prefix distinguishes them.

### Creating IDs

```go
import "github.com/xraph/chronicle/id"

auditID   := id.New(id.PrefixAudit)    // audit_01h455vb...
streamID  := id.New(id.PrefixStream)   // stream_01h455vb...
erasureID := id.New(id.PrefixErasure)  // erasure_01h455vb...
```

Convenience constructors: `id.NewAuditID()`, `id.NewStreamID()`, `id.NewErasureID()`, `id.NewReportID()`, `id.NewPolicyID()`, `id.NewArchiveID()`, `id.NewPluginID()`.

### Parsing IDs

```go
parsed, err := id.Parse("audit_01h455vb4pex5vsknk084sn02q")
parsed, err := id.ParseWithPrefix("audit_01h455vb...", id.PrefixAudit)  // validates prefix
parsed, err := id.ParseAuditID("audit_01h455vb...")                     // convenience
```

### Nil ID

```go
var empty id.ID
empty.IsNil()  // true
empty.String() // ""
id.Nil.IsNil() // true
```

### Database storage

`id.ID` implements `Scanner` and `driver.Valuer`. Stores as a string, returns `NULL` for nil IDs.

### JSON serialization

`id.ID` implements `TextMarshaler` and `TextUnmarshaler`. Nil IDs serialize as empty strings.

## Prefix reference

| Constant | Prefix | Entity |
|----------|--------|--------|
| `id.PrefixAudit` | `audit` | Audit event |
| `id.PrefixStream` | `stream` | Hash chain stream |
| `id.PrefixErasure` | `erasure` | GDPR erasure record |
| `id.PrefixReport` | `report` | Compliance report |
| `id.PrefixPolicy` | `retpol` | Retention policy |
| `id.PrefixArchive` | `archive` | Retention archive |
| `id.PrefixPlugin` | `plugin` | Plugin registration |