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Notes on building AI voice agents that ship

Platform comparisons, latency engineering, real costs, and the parts of a voice pipeline nobody warns you about.

Vapi vs Retell vs LiveKit vs Pipecat: Which Voice AI Stack in 2026

Voice AI·

Four ways to build a voice agent, compared on latency, real cost per minute, control and the work you inherit. Written by someone who has shipped on more than one of them.

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AI Voice Agent Cost in 2026: What It Really Costs to Build and Run

Voice AI·

Build costs from $4,000 to $45,000, running costs from $0.04 to $0.25 per minute. A line-by-line breakdown of where the money actually goes, and the costs that never appear in the first quote.

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Voice Agent Latency: Where the Seconds Actually Go, and How to Get Them Back

Engineering·

Under 800ms feels alive. Past 1.5s people talk over the agent. A stage-by-stage breakdown of the latency budget and the eight fixes that actually move the number.

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Speech-to-Speech vs Chained STT-LLM-TTS: Choosing a Voice Architecture

Engineering·

Speech-to-speech wins on latency and naturalness. Chained pipelines win on control, cost and auditability. How to pick, and why most production systems I build end up chained.

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Migrating Off Vapi or Retell: When It Is Worth It, and How to Not Break Things

Voice AI·

The four reasons that justify a migration, the work managed platforms were quietly doing for you, and a cutover sequence that does not let customers discover the new stack is worse.

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Securing LLM API Keys in Production: A Practical Guide

Engineering·

Leaked model API keys are one of the most common and most expensive AI production failures. Server-side proxying, key scoping, budget caps and the monitoring that catches abuse early.

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App Development Cost 2026: Detailed Pricing Guide & How to Optimise

Mobile App·

App development cost ranges from $1,200 to $200,000+ depending on complexity, platform, and team. Realistic 2026 pricing, the 7 factors that drive cost, what AI actually saves you, and the hidden fees no one puts in the first quote.

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