Nacho Coll — Founder, Zellbox

Background

I’ve been building on AWS since 2007 — from the very early days of S3 and EC2, long before “cloud” was the default answer. As an AWS Enterprise Architect I designed production-scale systems for top-tier customers including LEGO, Nordea, Vueling, and others in the enterprise Fortune-500 tier. That’s where the operational instincts behind everything I do today were formed: cost discipline, multi-region reliability, and taking observability seriously from day one rather than bolting it on later.

Since 2020 I’ve been focused on two things in parallel: WhatsApp Business Platform infrastructure for appointment-driven small businesses, and the AI side of software delivery — bringing the same enterprise-architecture discipline to both. That’s the foundation Blockchain Web Services (BWS) runs on today: an AI-native solutions factory with a single operating slogan, Demand Becomes Product. We turn validated market demand into production-ready software — engineered by people, accelerated by AI, accountable end-to-end. Every line of code that ships from BWS is owned by a named engineer.

BWS ships several production products from that same discipline. Zellbox is one of them; others include:

Zellbox — WhatsApp-first calendar and customer record system for appointment-driven SMBs: clinics, salons, spas, physio, aesthetics, vets, mental-health, and fitness.
OpenAgile.AI — engineering discipline for AI-assisted development.
WallaWhats — real-time WhatsApp alerts when your favorite X/Twitter accounts post.
Badges.ninja — blockchain-verified digital badges with a visual designer and REST API.
IPFS.NINJA — the simplest IPFS pinning and upload API, with dedicated gateways and a generous free tier.
Blockchain Database — a single API to use the blockchain as a data layer.
NFT.zK — a straightforward API to mint NFTs without Web3 expertise.
Telegram XBot — a Telegram bot that tracks X activity and highlights top community contributors.

BWS pivoted to being AI-native in mid-2025. AI wasn’t a feature we added — it’s a company we became. The engineering bar didn’t change: what changed is how much research, scaffolding, and testing AI can now carry, so a small team can ship the same shape of production software that used to take a much larger one.

What we work on day-to-day

My day-to-day spans the whole BWS solutions portfolio — directing roadmaps across the products, reviewing technical design with the team, tightening the AI-assisted delivery workflow that ships all of them, and keeping the engineering discipline consistent from one product to the next. Each product has its own weekly cadence; my job is the connective tissue between them.

For Zellbox specifically, we focus on the operational surface every appointment-driven small business runs on — WhatsApp conversations, a calendar, a customer record, and payments — and make each of those work well enough that operators don’t need a four-tool patchwork. Areas the team has been hands-on with recently:

Two-way WhatsApp linked to the customer record. Every message a customer sends threads onto their profile automatically — no separate inbox to switch to, no manual copy-paste from a Business App to a CRM. Operators reply from the same screen they book from, and every historical conversation is one click away from the next appointment.
No-show reduction, end to end. Reminder cadences that actually reduce cancellations (per-appointment-type intervals, quiet hours, reply-to-confirm flow), plus Stripe-native deposits for appointment types where the operator needs a financial commitment. One workflow for every vertical, tuned by the operator not us.
Recall automation. Every appointment-driven business runs on return visits — a hygiene appointment, a color refresh, a physiotherapy follow-up, a maintenance session. Operators define per-service recall intervals once; Zellbox runs the WhatsApp send calendar and books the follow-up straight back into the calendar.
Google Calendar sync (two-way). Every appointment change on either side stays in sync — operators can use whatever they already had (Google Calendar on the phone, a shared team calendar, a desktop client) alongside Zellbox without duplicated events or missed edits.
Send-and-sign consent flows. For businesses under GDPR / LOPDGDD / equivalent regimes, we ship a WhatsApp-native consent flow: send the PDF, customer signs on their phone, signed file lands on the customer record with the audit trail attached. Every vertical that touches customer data — clinics, wellness, beauty, fitness memberships — uses the same primitive.
Multi-locale approved WhatsApp templates. Meta’s message-template approval rules change constantly. We maintain a registry of approved templates per locale (12 supported today) so operators never have to draft their own and wait for Meta approval. The src/@common/wa-platform-templates.mjs registry is the source of truth for what actually ships to a customer’s inbox.
Customer import + team seats. Bulk import from spreadsheets or the previous tool operators are migrating off, plus multi-seat team calendars with staff-level permissions and per-staff booking links. What used to be a data-migration project becomes an upload.
Analytics that answer the operator’s questions. No-show rate, recall response rate, revenue per customer, LTV by acquisition source — the numbers a small-business owner actually asks at the end of the month, not a dashboard of vanity metrics.
Customer support. We handle every ticket directly. If you email hello@support.zellbox.com, you’ll get a response from a real human — and most days, that human is me.

Articles I’ve written or reviewed

Most posts on this site carry my byline. Some are drafted by an AI assistant (see the editorial process for the full workflow) and reviewed by me before publication; others are written end-to-end by the team. Either way, every WhatsApp template body cited in an article is verified against the approved production templates before publishing.

A few representative posts:

Callbell vs Zellbox for Clinics — an honest, feature-level comparison for clinic owners choosing between the two platforms.
How to Send WhatsApp Reminders in a Dental Clinic — hands-on operational runbook for cutting no-shows on the dental vertical.
24-hour cancellation policies + bono economics for physio clinics — the math behind deposit-backed cancellation policies.