Skuld

Skuld · Arrival — Built in 10 days. Designed to outlive a conversation. During the Meta Global AI Developer Hackathon, we built Skuld · Arrival: an open-source persistent AI runtime and Terminal that lets language models carry state, responsibility, and action history beyond a single context window. Modern models can reason about the world, but most applications reset at the end of a session. Skuld changes the unit of continuity from a conversation to an evolving subject. It maintains source-linked observations, world state, beliefs, goals, commitments, predictions, tool actions, and outcomes in a persistent store. A session can end without erasing what happened or what remains unfinished. What we built in ten days: A persistent subject runtime. Skuld connects model reasoning to durable world state and maintains the evidence and consequences of decisions across sessions and process restarts. Skuld Terminal and Pi integration. The desktop Terminal exposes the agent's state, conversations, and tool results. The V4 runtime controls session state and action authorization; the Pi harness handles model turns and guarded operations. Local workspaces are isolated, and write operations require explicit approval. World understanding and proactive action.Skuld organizes events and their sources, tracks unfinished commitments, and provides a foundation for comparing expectations with new observations—so the agent can investigate meaningful changes rather than simply react to a new prompt. Meta-powered long-horizon validation. We self-hosted Meta's open-weight Muse Glimmer 30B with SGLang and connected it to Skuld's decision-and-tool loop on Prosus Vending Bench. The recorded run covered 30 simulated days, with 193 returned model calls and 535 environment-counted tool calls. After a day-10 process restart, the agent continued from its previous state, investigated an outstanding complaint, made a €8.14 simulated refund, received confirmation, and kept operating. The run reached completion after a day-28 checkpoint continuation with a higher request cap. Our goal is not a chatbot with a bigger memory. It is intelligence that can maintain a relationship with the same changing world, remain accountable for the consequences of its actions, and carry unfinished work into tomorrow. Not an AI you open. An AI that stays. Skuld · Arrival. Time to live.