EventFactory

EventFactory is the low-level builder in applesauce-core.

It is an awaitable chain of event transforms. Each method returns another factory instance, and the whole chain resolves to an event draft. Finish the chain with .stamp() or .sign() when you need a pubkey or a full signed event.

What It Is

You can start from a kind number or an existing event:

import { EventFactory } from "applesauce-core";

const draft = EventFactory.fromKind(1).content("Hello");
const signed = await draft.sign(signer);

import { EventFactory } from "applesauce-core";

const edited = await EventFactory.fromEvent(existingEvent).content("Updated").sign(signer);

How To Use It

Start a blank draft

const draft = EventFactory.fromKind(30023)
  .content("Article body")
  .alt("Long-form article")
  .modifyPublicTags((tags) => [...tags, ["title", "Hello"]]);

Reuse a signer across the chain

const signed = await EventFactory.fromKind(1).as(signer).content("Hello").sign();

Modify tags

import { addProfilePointerTag } from "applesauce-core/operations/tag/common";

const signed = await EventFactory.fromKind(3).modifyPublicTags(addProfilePointerTag(friend)).sign(signer);

Stamp And Sign

Use .stamp() when you need an unsigned event with a pubkey:

const unsigned = await EventFactory.fromKind(1).content("Hello").stamp(signer);

Use .sign() when you need a full NostrEvent:

const signed = await EventFactory.fromKind(1).content("Hello").sign(signer);

.sign() checks that the signer does not change the event kind or stamped pubkey.

Integration

EventFactory is the base layer used by typed factories in applesauce-common/factories.

import { NoteFactory } from "applesauce-common/factories";

const note = await NoteFactory.create("Hello #world").sign(signer);

If a built-in typed factory does not exist, use EventFactory directly and compose low-level operations.

Best Practices

• Use fromKind() for new events and fromEvent() for edits
• Call .as(signer) when multiple later steps need the signer
• Keep repeated logic in operations instead of inline tag mutation
• Prefer typed factories for notes, comments, lists, profiles, messages, and other event kinds defined in NIPs