QCon London: AI Coding Agents Now Cost $91K/Year Per Developer, Run Unsupervised 20 Minutes, But Security Incidents Weekly

InfoQ reports from QCon London that AI coding agents have advanced dramatically but carry escalating costs and security risks. Agents now operate unsupervised for up to 20 minutes and integrate directly into CI/CD pipelines via headless CLI modes. However, costs have exploded from $0.12 per 100 lines in 2024 to approximately $380/day ($91,200 annualized) — equivalent to developer salaries in some markets. Weekly security incidents involving prompt injection are now routine; one attacker used a crafted GitHub issue to extract secrets and upload malicious NPM packages. Thoughtworks principal consultant Birgitta Böckeler proposed a risk framework evaluating AI tools across probability of mistakes, impact severity, and error detectability.