Kind 9041: Zap Goal

Overview

Zap Goal events (kind 9041) define fundraising or donation targets using the Lightning Network zap system. These events allow creators, projects, or causes to set specific funding goals, track progress, and provide milestone information for funding campaigns in the Nostr ecosystem.

Specification

Property	Value
Kind Number	9041
Event Range	Regular
Defined in	NIP-75

Content Format

The content field contains a description of the zap goal, explaining its purpose, benefits, or other relevant details.

Schema

"content": "Help me fund the development of my new open-source Nostr client. All donors will get early access to beta releases!"

Tags

Tag Name	Description	Format	Required
amount	Target amount in millisatoshis	["amount", "<millisats>"]	Yes
title	Short title for the goal	["title", "<title>"]	Yes
summary	Brief summary of the goal	["summary", "<summary>"]	No
image	Image URL for the goal	["image", "<url>"]	No
start	Start time (unix timestamp)	["start", "<timestamp>"]	No
end	End time (unix timestamp)	["end", "<timestamp>"]	No
e	Related event reference	["e", "<event-id>", "<relay-url>"]	No
a	Related parameterized event	["a", "<kind>:<pubkey>:<d-identifier>"]	No
p	Related people/collaborators	["p", "<pubkey>"]	No
milestone	Milestone definitions	["milestone", "<sats>", "<description>"]	No

Client Behavior

Clients should:

1. Display zap goals with their title, amount, and progress
2. Calculate progress by summing zap receipts (kind 9735) that reference the goal
3. Show milestone markers when relevant funding levels are reached
4. Indicate when goals are completed (funding meets or exceeds the target)
5. Allow users to zap directly from the goal display
6. Show time remaining for goals with end dates

Relay Behavior

Relays should:

1. Store zap goal events like any other event
2. Ideally index these events to enable efficient discovery
3. Help connect zap receipts to their corresponding goals

Use Cases

• Crowdfunding for open-source projects
• Setting donation targets for content creators
• Fundraising for causes or charitable initiatives
• Creating incentivized milestone funding for development
• Tracking progress toward community goals

Example

{
  "id": "df0d11faa62a17372c5ee9a2b3f15ab52e8d1fadab3218b392d28d2a6f386627",
  "pubkey": "32e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245",
  "created_at": 1684500000,
  "kind": 9041,
  "tags": [
    ["amount", "210000000"],
    ["title", "Fund My Open Source Nostr Client"],
    ["summary", "Help me build a new accessible Nostr client for everyone"],
    ["image", "https://example.com/project-image.jpg"],
    ["start", "1684500000"],
    ["end", "1689684000"],
    ["milestone", "50000000", "Alpha release to all donors"],
    ["milestone", "100000000", "Beta with group chat features"],
    ["milestone", "200000000", "1.0 release with all planned features"]
  ],
  "content": "I'm building a new Nostr client focused on accessibility and ease of use. Your donations will fund development time and infrastructure costs. All donors will get early access and special badges in the app!",
  "sig": "6d20367909814a09db053ec0616f98913af73b12c7f9187df47c9bea0c1c29ca4b61c989001fe9ecc9b3f38b8fc9f674c93b83f0b8b01c3addd5c7e34679619c"  
}

Zap Goal Progress Tracking

To track progress toward a zap goal:

1. Clients should look for zap receipt events (kind 9735) that reference the goal
2. A zap receipt references a goal when it contains an e tag pointing to the goal's event ID
3. Sum the amounts from all valid zap receipts to calculate current progress
4. Compare the sum to the target amount in the goal's amount tag
5. Mark goals as complete when the sum equals or exceeds the target amount

Milestones

Milestones allow goal creators to define specific funding points with associated deliverables or rewards:

["milestone", "<millisats>", "<description>"]

Clients should highlight when a milestone is reached and display what it unlocks.

References

• NIP-75: Zap Goals

Related Kinds

• Kind 9734: Zap Request - Requests for Lightning Network payments
• Kind 9735: Zap Receipt - Receipts confirming Lightning payments

Notes

• Amounts for zap goals and milestones are specified in millisatoshis (1000 millisatoshis = 1 satoshi)
• Goals with an end date should be displayed with a countdown timer
• Expired goals (past their end date) should be marked accordingly
• Clients may implement additional features like goal leaderboards or donor recognition
• For privacy, clients can allow users to make anonymous contributions to goals