@rauchg: Itβs hard to fathom http://fx.sh getting even faster, but itβs nowβ¦ much faster As models speed up (as with Astra πποΏ½β¦
Summary
fx v0.0.13, a tiny native coding agent harness and CLI written in Zig, delivers major performance improvements including up to 23Γ faster launches, 8.6Γ faster shell calls, and 44Γ faster exits, with Ultrafast support for OpenAI models and better session storage/retrieval.
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Itβs hard to fathom http://fx.sh getting even faster, but itβs nowβ¦ much faster π
As models speed up (as with Astra πππππππππ), harness overhead matters more and more.
Next release will feature even better performance for session storage and retrieval, and a big unlock for cloud durability in libfx.
fx - Tiny, open, native coding agent
Source: https://fx.sh/ v0.0.13(notes)6.74mibstatus:experimentaluse at your own risk, we will be making frequent changes
This demo runs the full fx CLI as WebAssembly compiled with the Zig toolchain. Networking is delegated to browserfetch, and every SDK aspect is configurable in thedocs.
fx is a coding agent harness and CLI written in Zig, optimized for research and embeddability as part of larger systems.
It focuses on minimalism and performance across the board, from system prompt design to its tools, feature set, and 6.74 MiB binary.
Its output is closer to a Unix shell than an IDE in the terminal.
It is open source (Apache-2.0), model-agnostic, and suitable for both local and cloud inference.
Tiny native binary
Install one binary for your terminal, CI, or agent sandbox.
Fast startup
Start an interactive session or run a single request withfx ask. No background service is required.
WebAssembly support
Run the agent or terminal in the browser withlibfx. Your application controls storage, tools, and network access.
Shell-like UI and ergonomics
fx preserves scroll history and keeps tool activity in the conversation. Open the full transcript when you need more detail.
Context efficient
Concise tool schemas keep the context small. Skill instructions and MCP tool schemas load when needed.
Embeddable and extensible
Embed the core withlibfx, add your own tools, and connect skills or MCP servers.
Pranit (@fazxes): fx v0.0.13
Ultrafast support. Faster launch, shell calls & exits.
β’ Ultrafast for supported OpenAI models β’ Launch up to 23Γ faster β’ Shell calls up to 8.6Γ faster β’ Exits up to 44Γ faster β’ Configurable automatic compaction β’ Multiple bug fixes & security improvements
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