Lightspeed
smartcomputer-ai/lightspeed
A deterministic agent harness for Temporal, in Rust.
Lightspeed is a deterministic agent harness built on Temporal and written in Rust — event-sourced, durable execution for agents that treats the workflow engine as the harness. A small project with a sharp thesis.
In the news
Temporal raises $300M Series D at $5B valuation
Durable-execution leader Temporal closes a $300M Series D led by a16z at a $5B valuation, reporting 380% YoY revenue growth and 20M+ monthly installs. The agent-infra thesis in one round: in-memory agent state breaks in production, and durable execution is the production architecture.
DeepSeek ships Harness Desktop; the 'everything is a plugin' harness passes 240k stars
DeepSeek releases a macOS and Windows Desktop app for DeepSeek Harness, its open-source agent harness where everything — tools, sub-agents, even the loop — is a plugin. The repo passed 240k stars within three months of its August launch, making it the fastest-growing harness in the field's history.
Restate raises $20M Series A for agent infrastructure
Restate raises $20M to 'define the infrastructure layer for AI agents and workflows' — its lightweight durable runtime journals every agent step so invocations survive crashes. The round underlines durable execution as the best-funded sub-category of agent infrastructure.
HarnessTax: harness choice swings agent cost more than model choice
Arena.ai's HarnessTax study tests 21 model–harness combinations across Claude Code, Codex CLI and Pi, finding harness choice can significantly change cost even at similar task success rates. Weeks earlier, SWE-bench Pro analysis showed swapping harnesses moved pass@1 more than model upgrades (23%→52% on GLM-5.2) — and that harness rankings barely transfer across models.
Related projects
superpowers
obra/superpowers
An agentic skills framework and software methodology that works.
superpowers is the most-adopted skills pack in harness engineering: skills, instincts, memory, security and research-first workflows for Claude Code and 13 other harnesses (Codex, Cursor, opencode, Gemini CLI and more). Treats harness engineering itself as the discipline.
DeepSeek Harness
deepseek-ai/deepseek-harness
Everything is a Plugin — DeepSeek's open agent harness.
DeepSeek Harness is the breakout open-source harness of 2026: an architecture where everything — tools, subagents, even the loop itself — is a plugin. A Desktop app for macOS and Windows followed in October 2026, and the project passed 240k stars in under three months.
opencode
anomalyco/opencode
The open source coding agent — terminal-first, model-agnostic.
opencode is a blazingly popular terminal coding agent: a language-server-backed TUI that works with any provider, scriptable and hackable. Its growth made it the open counterweight to Claude Code.