About Carl
Carl is a senior full-stack engineer with around 12 years building products end to end, from the UI a user touches down to the AI agents and Ethereum protocols underneath. Most of his current work is applied AI: conversational voice and SMS agents running on real-time telephony that answer calls, qualify leads, and surface the urgent ones. He built one such system, Svarar Alltid, which captured 58 qualified jobs across 4 pilot businesses in its first three months. He's strongest in TypeScript and Next.js, and works best with teams that have a genuinely hard problem and want someone to own it. He also writes Solidity and authored two Ethereum standards.
Swedish
Native or bilingual
English
Fluent
Remote only
Primarily works remotely
Experience
- Svarar AlltidFounder & Full-stack EngineerJanuary 2026 - Today (6 months)Founded and built an AI-receptionist platform that captures missed calls for Swedish tradespeople. A missed call triggers an SMS reply in seconds, the agent qualifies the lead, and the owner gets an urgency-sorted summary. The voice pipeline runs on a custom SIP-to-WebSocket gateway paired with LLMs for low-latency phone conversations. Full stack in TypeScript, Next.js, and React, covering telephony, lead-qualification logic, and the owner dashboard. In its first three months of pilot it handled 189 conversations from 134 callers and captured 58 qualified jobs across 4 businesses.
- Zephyr Valley ABFounder & Senior Full-stack EngineerJanuary 2020 - Today (6 years and 6 months)Freelance full-stack and Web3 engineering consultancy. Built financial platforms with Next.js and Shadcn UI, often from Figma designs, authored ERC-8185 and ERC-8186 — Ethereum standards for off-chain entity resolution and claimable escrow. integrating blockchain wallets via RainbowKit and Wagmi. Developed full-stack MVPs with Next.js, tRPC, Prisma, and Supabase. Built fintech prototypes integrating Stripe for payments. Developed AI-powered voice products pairing LLMs with real-time SIP/WebSocket telephony for conversational phone agents.
- allo.capitalFull-stack & Protocol EngineerDecember 2024 - June 2025 (6 months)Contributed to R&D and engineering for a permissionless capital-allocation protocol built on Ethereum. Developed Solidity smart contracts and the supporting TypeScript and React tooling. Supported business development and partner integrations alongside core protocol engineering.
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Education
- Linnéuniversitetet / Linnaeus University2012