iMessage automations with Zapier, n8n or Make

Who uses iMessage for no-code automations?

ZeroSettle with Zapier, n8n or Make is for ops people and no-code builders who already run the business on those tools and want iMessage in their flows without writing or hosting a server. ZeroSettle is an iMessage API: a real phone number on real iMessage, running on Apple hardware we operate for you, that your code texts customers from and hears back on through a bearer token and signed webhooks. In this setup, your automation tool plays the part of the code.

For CRM logging, see iMessage in HubSpot or Salesforce. For a team inbox, see support routed to Slack. Other jobs are in the use-case index.

How iMessage for no-code automations works, step by step

Every ZeroSettle automation has four steps: a webhook trigger, a signature check, a branch on the event type, and an HTTP send. The rules are the same ones a coded receiver follows (see how ZeroSettle webhooks work).

1. Trigger. An n8n Webhook node, a Zapier Catch Raw Hook or a Make custom webhook receives the POSTs. You register its URL once with PUT /api/imessage/webhook and store the signing secret, which is shown only once.
2. Verify. A code step computes the HMAC-SHA256 of "<t>." + raw body with the secret, compares it with v1, and rejects any t more than 300 seconds from now.
3. Branch. Continue only on message.received. Your own sends echo back as message.sent, and tapbacks arrive as reaction.received. Retries carry the same message.id and event, so skip ids you have already handled.
4. Send. An HTTP Request step calls POST https://portal.zerosettle.io/api/imessage/send with Authorization: Bearer and your token.

Sources: n8n Webhook and Code node docs and Webhook node source, Zapier's webhook and JavaScript help, Make's Webhooks and text-function docs (linked under Sources).

Example conversation: no-code automations

In this thread, an n8n flow answers an hours question from a Google Sheet. The customer texted first, so the thread never counts against a new-contact limit.

Behind the thread, "sunday" matched a sheet row, and the HTTP step sent that row's answer. The flow dropped the reply's message.sent echo and the ❤️ (reaction.received), so it didn't answer a heart. "Hold 2 loaves" matched no row, so the flow alerted staff.

Setup: a webhook node, a verify step and an HTTP request

A ZeroSettle flow needs one registration call, a verify step and an HTTP request. The n8n version is below. The full receiver rules are in the webhooks section of the ZeroSettle docs.

Register the production URL

export BASE=https://portal.zerosettle.io     # TOKEN holds your API token from the console
curl -s -X PUT -H "Authorization: Bearer $TOKEN" -H 'Content-Type: application/json' \
  -d '{"url":"https://YOUR-PRODUCTION-WEBHOOK-URL"}' $BASE/api/imessage/webhook

In n8n's Webhook node, set HTTP Method to POST, Respond to Immediately, and turn on Raw Body under Options. Then register the production URL and publish the workflow, because the test URL listens only while you wait for a test event. Registering again rotates the secret.

Verify in a Code node

// n8n Code node, "Run Once for All Items", after a Webhook node with Raw Body on
const crypto = require('crypto');
const SECRET = $vars.ZEROSETTLE_WEBHOOK_SECRET;   // an n8n Variable; see below
const raw = await this.helpers.getBinaryDataBuffer(0, 'data');   // exact bytes received
const m = /^t=(\d+),v1=([0-9a-f]{64})$/.exec($input.first().json.headers['x-zerosettle-signature'] || '');
if (!m || Math.abs(Date.now() / 1000 - Number(m[1])) > 300) return [];
const expected = crypto.createHmac('sha256', SECRET).update(`${m[1]}.`).update(raw).digest('hex');
if (!crypto.timingSafeEqual(Buffer.from(expected), Buffer.from(m[2]))) return [];
const ev = JSON.parse(raw.toString('utf8'));
if (ev.event !== 'message.received') return [];   // drop message.sent echoes and reactions
return [{ json: ev.message }];                     // handle, id, text, kind, image

Returning no items stops the run. n8n Cloud provides crypto; self-hosted instances need NODE_FUNCTION_ALLOW_BUILTIN=crypto. Variables ($vars) need n8n Cloud Pro or Enterprise, or self-hosted Business or Enterprise. Self-hosted, $env also works, but since n8n 2.0 only with N8N_BLOCK_ENV_ACCESS_IN_NODE=false. Otherwise the secret sits in the node, readable by anyone who can edit the workflow.

In Code by Zapier, map the Catch Raw Hook's raw body and signature header into inputData, set output to {valid: …}, and stop the Zap with a Filter step on valid. In Make, sha256 with a key returns the HMAC, and a filter compares it with v1 (a plain comparison, since Make documents no constant-time one).

Send with an HTTP Request node

Use POST to https://portal.zerosettle.io/api/imessage/send with a Header Auth credential (Authorization: Bearer plus your token), so the token stays in n8n's credential store. The JSON body is {"to": "{{ $json.handle }}", "text": "…"}. In the node's options, set Timeout to 90,000 ms: a text send normally returns in 2–5 seconds but can take about 75. Turn on Never Error so you can branch on error.code, such as line_busy or new_contact_limit.

Three starter flows

Inbound HEIC photos arrive as JPEG, and inbound video and files arrive without the file. For a receipt version of the photo flow, see clients texting receipts to a bookkeeper.

Failure modes specific to automation tools

• The tool answers before the flow runs, so ZeroSettle never retries a step that fails later. Rerun failed runs from your tool's run history. Don't add Make's Webhook response module or n8n's "When Last Node Finishes" after slow steps: Make waits up to 180 seconds, but ZeroSettle stops at 10 and retries, so one event can start up to four runs.
• The flow is off or full. Zapier returns 404 for a Zap that is off, but only after a delay of up to several hours; until then it answers 200, so ZeroSettle never retries. Make answers 400 when its webhook queue is full. ZeroSettle retries a 404 or 400, then records the failure in GET /api/imessage/line → last_delivery.
• The run starts late. A run that starts more than 300 seconds after signing fails verification. Zapier warns that webhooks can be delayed when many requests arrive at once.
• Sends overlap. Parallel sends wait in line and return 429 line_busy after about 12 seconds. Retry after 2 seconds.

Limits and consent for no-code automations

ZeroSettle limits an automation like any other caller: replies to people who texted first are unlimited, so only text-first flows such as the order thank-you count against new-contact limits. Outbound triggers should fire only for customers with a stored consent flag.

Limit math for 12 first-time buyers in 15 minutes: on Pro, the first 5 thank-yous go out and the other 7 get 429 new_contact_limit for the day, so the flow holds them until after the 3 AM Eastern reset (or skips them). On Growth, each number takes 3 new contacts per 15 minutes, and ZeroSettle sends a new contact from whichever number has room. With three numbers, the first 9 go out as the orders come in, and the other 3 about 15 minutes after the first; the flow waits retry_after_s and retries.

When ZeroSettle is not a fit for no-code automations

ZeroSettle in a no-code tool is the wrong choice when the tool can't verify signatures, when volume is high, or when your customers aren't on iMessage.

• Your tool can't give you the raw body. Zapier's plain Catch Hook parses the body, so the exact bytes are gone. A flow that can't verify signatures can be triggered by anyone who learns the URL (see how ZeroSettle secures tokens and webhooks).
• You need high throughput. Each line sends one message at a time, and a send normally takes 2–5 seconds.
• Your tool's usage costs outweigh the benefit. Every event starts a run in your tool, including the message.sent echo of each reply and every tapback.
• You expect a native Zapier app. None exists for Zapier, n8n or Make. You use webhook and HTTP steps.
• Many buyers use Android. There is no SMS fallback, so keep email for them.

How much does iMessage for no-code automations cost?

ZeroSettle costs the plan price, with no per-message fees. Messages are unlimited and counted. Your automation tool bills separately: Webhooks by Zapier, for example, needs a Professional, Team or Enterprise plan.

Both plans carry a 30-day money-back guarantee, and a line your own flow answers uses no AI credits. See pricing or get a number.