What we learn running in production.
No generic “5 tips to boost engagement” posts. We write about architecture decisions, Meta rule changes, real channel cost, and what we found out when something broke.
The WhatsApp 24-hour window: what opens it, what closes it, and where the math goes wrong
Every Cloud API integration runs into the same rule, and most of them get the same piece of it wrong. The window doesn't start when your server processes the webhook — it starts at the timestamp Meta sent inside it.
CCX Engineering · Platform · Channel rules · Aug 19, 2026 · 7 min readRead the featured post
Everything we've published so far.
20 posts. Written by the people who ran the problem — engineering, product, or delivery — not an agency.
WhatsApp Cloud API: what it is and how to integrate it (number, token, webhook and first message)
The WhatsApp Cloud API is the official WhatsApp API for businesses, hosted in Meta’s cloud: your system sends messages over HTTP and receives replies and statuses by webhook. A direct integration needs four pieces: a registered number, a permanent token, the first message and a webhook that survives redeliveries. Here is what Meta’s documentation says about each one today, and the traps you meet in production.
CCX Engineering · Platform · Engineering · Oct 28, 2026 · 10 min read
WhatsApp Flows: what they are, how to build them and when to use in-chat forms
WhatsApp Flows are multi-screen forms that open inside a WhatsApp conversation, with fields, lists, dates and buttons, without the person leaving the app. They handle sign-ups, appointment booking, surveys and quotes, and the answer comes back to the business as a message. Here is how they work on the API, how to build and send a Flow, what to do with the response and where Meta sets limits.
CCX Product · Product · Channel rules · Oct 28, 2026 · 10 min read
WhatsApp Business verified badge: what it is, how to get it and how to avoid scams
The WhatsApp Business verified badge is the blue checkmark next to a business’s name, which tells customers Meta has confirmed who is on the other end. There are two ways to get it: the Meta Verified subscription in the app, and Official Business Account status on the API. Business verification in your Meta business portfolio, which people often confuse with both, gives you no badge at all. Here is how each one works, how to apply, why Meta says no and how to spot people selling a guaranteed badge.
CCX Product · Product · Channel rules · Oct 28, 2026 · 10 min read
WhatsApp customer service: how to set up your company’s support
WhatsApp customer service is your support operation on the channel customers already use: they write when it suits them, send a photo of the problem and follow the reply without waiting on hold. Opening the channel is easy; organizing it is the hard part. Here is how to move support off someone’s phone and build an operation with an official number, triage, a queue, deadlines, Meta’s rules and Brazil’s customer service decree, and metrics that show whether customers were helped.
CCX Operations · Delivery · Operations · Oct 28, 2026 · 10 min read
WhatsApp chatbot: what it is, how it works on the official API and when to use AI
A WhatsApp chatbot is a program that talks to customers with no person on the other end: it answers questions, shows options, collects details and hands over to a human agent when needed. Today it can be a menu of buttons or an AI agent that understands what the customer wrote. Here is what each one does well, what Meta allows, what goes into the cost and how to build one without annoying the person on the other side.
CCX Engineering · Platform · Channel rules · Oct 23, 2026 · 10 min read
WhatsApp bulk messaging: how to do it through the official API without losing your number
WhatsApp bulk messaging means sending the same message to many people at once, and there are three ways to do it: the app's broadcast list, tools that automate WhatsApp Web, and Meta's official API. Only the last one was built for this. Here is how each one works, why “ban-proof” tools get numbers banned, what Meta requires, and what actually keeps a campaign running.
CCX Operations · Delivery · Channel rules · Oct 23, 2026 · 10 min read
WhatsApp CRM: what it needs, how it works with the official API and what it costs
A WhatsApp CRM is the system that connects WhatsApp conversations to what the business knows about the customer: who they are, what they bought, which stage of the sale they’re in and who on the team handles them. Without it, the sale lives on each salesperson’s phone. Here is what a WhatsApp CRM needs, the two ways to connect WhatsApp to it, how a shared inbox works and how to compare prices without getting stuck with per-seat pricing.
CCX Product · Product · Operations · Oct 23, 2026 · 10 min read
The official WhatsApp Business API: what it is, how to get it and what it costs in 2026
The official WhatsApp API is the path Meta offers for a business to talk to customers from a system, not from a phone. It charges per message and follows rules the app doesn't have. What it is, how it differs from the app and from the unofficial API, how to get there, what it costs, which limits apply and what changes between 2026 and 2027.
CCX Product · Product · Channel rules · Oct 21, 2026 · 12 min read
What is omnichannel? How it works behind the scenes and where the chatbot fits
Omnichannel means serving customers across many channels as if it were one conversation. The definition fits in one sentence; the hard part is behind it. Each channel has its own reply rules, its own way of identifying the person and its own consent, and that is where most multichannel customer service stops being omnichannel. What it is, what changes in practice, and where the chatbot and AI fit in.
CCX Product · Product · Channel rules · Oct 21, 2026 · 10 min read
Automatic messages on WhatsApp Business: how to set them up and when to move to the API
The WhatsApp Business app already sends three kinds of automatic message for free: the greeting message, the away message and quick replies. Setup takes five minutes, and the step-by-step guide is here, with ready-made templates. What takes longer to notice is where the app stops: one greeting for everyone, no conditions and no history. That's where automation moves to the API.
CCX Operations · Delivery · Channel rules · Oct 21, 2026 · 10 min read
WhatsApp template categories: why your utility template became marketing
Meta does not take the category you choose at face value: it checks the content, approves as marketing whatever it thinks is marketing and, since September 2026, re-evaluates approved templates by the messages they send. The category decides the price, the limits and, from 2027, even the API the message goes out through. What separates utility from marketing, how recategorisation gives notice and what to do when it arrives.
CCX Engineering · Platform · Channel rules · Oct 17, 2026 · 15 min read
WhatsApp error 131049: the marketing message Meta decided not to deliver
Error 131049 is not a technical failure, it is not a block on your number and retrying does not fix it. It is Meta saying that this person has already received too much marketing — yours and every other business's — and that resending within 24 hours only returns another 131049. How to read the error, tell it apart from its neighbours, measure its effect on a campaign and prepare for the end of marketing on the Cloud API in 2027.
CCX Engineering · Platform · Engineering · Oct 17, 2026 · 15 min read
WhatsApp coexistence: the Business app and the Cloud API on the same number
You can keep answering from the WhatsApp Business app on your phone and, at the same time, connect the same number to the Cloud API — without giving up the number your customers know or your chat history. Meta calls it onboarding business app users; the market calls it coexistence. What it requires, what changes in the app, the 24 hours you do not get back and what the integration has to do to avoid ruining six months of history.
CCX Engineering · Platform · Channel rules · Oct 17, 2026 · 15 min read
The CCX Messages partner program: 20% every month, a year-end bonus, and we handle the sale
The program fits in one line: A + B. A is 20% of the subscription of every client you refer, every month, for as long as they stay a client. B is a 1% to 4% bonus on your portfolio's message spend for the year. This post shows how the two add up, what counts as a referral and how the money reaches you.
CCX Product · Product · Partnerships · Oct 17, 2026 · 10 min read
RCS got end-to-end encryption. The spec doesn't say how far it reaches.
The GSMA announced E2EE for RCS over MLS, in the same text that covers improvements to business messaging. Anyone filling in a security questionnaire needs to know whether their own traffic sits inside that scope — and neither primary source answers. This is about what to do with an answer that doesn't exist yet.
CCX Engineering · Platform · Channel rules · Aug 29, 2026 · 9 min read
The carrier's answer belongs to you, not to us
When a send fails, the carrier returns a reason. Keeping that reason and handing over only the label turns diagnosis into a support ticket — and moves work onto your team that had already been done. This is about why platforms do that, why we stopped, and what changes on call.
CCX Engineering · Platform · Engineering · Aug 28, 2026 · 8 min read
WhatsApp service message pricing: one goes down, the other never will
On 1 October 2026 Meta starts charging for two things that are free today, and the market is adding them up as if they pulled in the same direction. One of them starts counting toward your volume tier and can make what you already pay cheaper; about the other, Meta wrote in plain words that there will be no tiers at all.
CCX Engineering · Platform · Cost · Aug 26, 2026 · 9 min read
WhatsApp opt-in: what the law requires, what Meta requires, and where the two don't meet
Meeting Meta's policy is not meeting data protection law, and meeting the law won't protect you from a quality-based block. Two sets of rules with different foundations — and treating them as one means finding out the difference at the worst moment.
CCX Operations · Delivery · Operations · Aug 25, 2026 · 6 min read
131047, 131051 and 133010: what the Cloud API means when it rejects your message
Three codes that show up early in any WhatsApp integration, and whose documented names point at the wrong place. One of them blames the recipient when the problem is the sender.
CCX Engineering · Platform · Engineering · Aug 22, 2026 · 8 min readThe WhatsApp 24-hour window: what opens it, what closes it, and where the math goes wrong
Every Cloud API integration runs into the same rule, and most of them get the same piece of it wrong. The window doesn't start when your server processes the webhook — it starts at the timestamp Meta sent inside it.
CCX Engineering · Platform · Channel rules · Aug 19, 2026 · 7 min readThree editorial lines, none of them about us.
If a piece doesn't help someone make a better decision, we don't publish it. Product announcements go to the changelog, not here.
Real engineering
Architecture decisions and trade-offs we took, with the real numbers, not euphemisms.
Channel rules
Meta policy changes, carrier requirements, brand verification. What changes for you and by when.
Cost without euphemism
How each channel's price is built and what makes your bill rise without you noticing.
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