stupid wallet webhooks

Signed webhooks for EVM address activity. Point us at an address, tell us which chains to watch, and get a cryptographically-signed POST whenever that address sends a transaction, moves native value, or is involved in an ERC-20 or ERC-721 transfer — so you can trust an event without having to replay it.

How it works

Create a webhook. Give us an HTTPS endpoint; we return a one-time signingSecret so you can prove events came from us.
Subscribe an address. Choose the EVM address and chains (Ethereum, Base, Optimism, Arbitrum, …) to watch.
Get signed events. From its activation block onward, each matching transaction produces one event per address.
Verify and act. Dedupe on webhook-id and verify the HMAC signature, then trigger your own workflow.

What you get

Capability	Detail
Verified deliveries	HMAC-SHA256 signature over the exact event body (`webhook-signature: v1,<hex>`, ±5 min replay tolerance)
Activity	Top-level txs (incl. zero-value and reverted), incoming native value, ERC-20 and ERC-721 `Transfer`s
Chains	All chains*
Idempotent	Deterministic `webhook-id`; dedupe safely (at-least-once)
Delivery ledger	30-day history per webhook: every attempt, status, and outcome

* Supported chains depend on evm.stupidtech.net — a chain is supported when it resolves there.

Example event

A signed delivery looks like this (hashes abbreviated). The token contract is on each effect as assetAddress:

{
  "id": "evt_2f3d…",
  "type": "activity.observed",
  "createdAt": "2026-08-30T14:16:35.000Z",
  "data": {
    "chainId": 8453,
    "trackedAddress": "0xa0bfe1a0fc5b83d16e8599fd…e405",
    "initiatedByTrackedAddress": true,
    "blockNumber": "50655024",
    "transaction": {
      "hash": "0x198a0a…698",
      "index": 139,
      "from": "0xa0bfe1a0fc5b83d16e8599fd…e405",
      "to": "0xb13c82346dee41783e008b87f526d962aa3602d9",
      "status": "success",
      "value": "0"
    },
    "effects": [
      {
        "kind": "erc20",
        "direction": "outgoing",
        "logIndex": 277,
        "from": "0xa0bfe1a0fc5b83d16e8599fd…e405",
        "to": "0x377a…3d73",
        "assetAddress": "0xb13c82346dee41783e008b87f526d962aa3602d9",
        "amount": "3598000000000000000000"
      }
    ]
  }
}

Each token effect carries the token contract as assetAddress (erc20 adds amount; erc721 adds tokenId). A pure native transfer has effects: [] and value on the transaction.

What we watch (and what we don't)

Every mined top-level transaction from the address (successful, reverted, or zero-value).
Incoming native value on successful transactions.
ERC-20 and ERC-721 Transfers where the address is the sender or recipient.
We do not index internal call traces, re-simulate, or add token names / prices — events carry raw on-chain values only.
No historical backfill: activity only begins at each subscription's activation block. Shallow reorgs are compensated with an activity.reverted event.

The shape of it

POST /v1/webhooks        { "url": "https://you.example/hook" }        → signing secret, once
POST /v1/subscriptions  { "address": "0x1f9…", "chainIds":[8453,10,42161], "webhookId":"wh_…" }
GET  /v1/webhook-deliveries

Reliability & limits

At-least-once delivery; retry with exponential backoff (~24h), then a dead-letter queue an operator can replay.
Defaults: up to 1,000 active subscriptions and 20 distinct chains per account.
Signed test deliveries and a full delivery ledger are part of the API.

Skills

Agent-ready skills for this product live in the repo:

operator — run the live service: provision, health/lag, pause/resume, DLQ replay, deploy, metrics.
subscriber — set up webhooks, subscribe addresses, and verify signed deliveries.

Docs

Full reference: API reference.

Access is provisioned per account (an operator issues your API key). For access or support, contact hi@stupidtech.net.

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