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Twilio developer: SMS, calls, WhatsApp and OTP verification

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Listing period1 dayuntil 16.11.2026
Posted18.08.2026
Views1071 in 14 days

About the service

I am a developer who specializes in communications platforms and spends entire days working with Twilio, connecting it to your product so that every message and every call actually reaches the right person. For a typical backend engineer, messaging is just one function among many, but for me delivery, delays and compliance with the rules for working with phone numbers is the main task. I build SMS and voice call scenarios, WhatsApp Business dialogues and one-time passwords for verification that survive operator filtering, sender name restrictions and networks that silently lose traffic. When a code doesn't arrive or a call doesn't connect, I know how to read logs, follow status callbacks and find the real reason rather than guess.

Work almost always starts with a scenario, not code. We describe what the user should experience, how many attempts are allowed for OTP entry, what happens when a call is missed, how the IVR menu branches, and only then do I integrate all of this into your stack. I set up webhooks and status callbacks so the application always knows the real state of a message or call, I add retry logic and fallback channels so a single provider failure doesn't lose a customer, and I keep secrets and numbers where they belong — on the server, not on the client. Everything is built observable: structured logs, delivery reports and clear error paths that can be debugged even months later.

I seriously care about cost and deliverability because expensive or unreliable communication quietly harms all business. I help choose the right channel for each moment, switch from WhatsApp to SMS when needed, reasonably limit frequency and avoid mistakes that get sender names blocked. Whether you need transactional notifications, appointment reminders, two-way support chat or a full IVR call tree — I deliver a solution that your team can maintain long after handoff.

— SMS integration: transactional, marketing and OTP verification scenarios
— Voice and IVR: menus, call routing, recordings and speech synthesis
— WhatsApp Business messages and two-way dialog handling
— Webhooks, status callbacks, delivery reports, retry logic and fallbacks
— Deliverability, compliance with phone number rules and cost optimization

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