Implement payment notifications with reliable webhook delivery

[Just-Bamford]

Description

Problem

Applications currently need to poll account and transaction state to detect payment events. This increases API usage and introduces unnecessary latency.

There is no standardized notification infrastructure for payment lifecycle events or reliable webhook delivery.

Solution

Implement a payment notification subsystem with configurable webhook subscriptions.

Applications should be able to subscribe to events such as:

• payment_received
• payment_sent
• payment_failed
• payment_confirmed

Webhook delivery must include retry handling, request timeouts, event identifiers, and idempotency information so consumers can safely process duplicate deliveries.

Acceptance Criteria

• registerPaymentWebhook(url, events, options) is implemented.
• Supported payment event types are clearly defined.
• Webhook payloads include event ID, timestamp, transaction ID, account, and event type.
• Failed deliveries are retried using exponential backoff.
• Maximum retry attempts are configurable.
• Webhook requests have configurable timeouts.
• Duplicate event delivery can be identified through event IDs.
• Webhook registration and delivery errors are surfaced clearly.
• Optional notification channels can be integrated without coupling them to webhook logic.
• Tests cover successful delivery, retries, timeout, duplicate delivery, and failed endpoints.
• Exported through src/transaction/index.ts and src/index.ts.

Note for Contributors

Keep delivery infrastructure transport-agnostic where possible. Do not block transaction processing while waiting for webhook consumers. Ensure retry behavior cannot create an uncontrolled request loop.

[aristotle224]

@aristotle224 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I’d like to work on this issue because it addresses an important area of the project and presents a great opportunity to make a meaningful contribution. I’m particularly interested in delivering a solution that is reliable, maintainable, and aligned with the project’s existing architecture and development standards.

I have experience working across software development, including backend and frontend development, APIs, databases, testing, DevOps, and blockchain-based applications. I’m comfortable understanding existing codebases, identifying the root cause of issues, implementing clean and scalable solutions, and writing thorough tests to prevent regressions.

My approach would be to first understand the existing implementation and project conventions, then develop the solution in a focused and incremental way. I’ll ensure the changes are well-tested, documented where necessary, and do not introduce unnecessary complexity or break existing functionality. I’m also committed to clear communication, responding to review feedback, and delivering a polished contribution that provides real value to the project.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @aristotle224 to this issue.

[Peolite001]

@Peolite001 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

i would love to work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Peolite001 to this issue.

[connelevalsam]

@connelevalsam has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I will like to work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @connelevalsam to this issue.

[drips-wave]

Congratulations, @connelevalsam! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

🧑‍💻 @connelevalsam: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊