flux

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What flux is

Flux is a free, open-source AI coding assistant that runs in a terminal on Linux and macOS. Built with Go and tuix, its keyboard-driven interface provides slash commands, model switching, file diffs, and a live status bar. Flux can index codebases, read and write workspace files, search code, find files, and run shell commands, including independent tool calls in parallel when safe. It supports OpenRouter, OpenAI, and Anthropic, with API keys supplied through environment variables and models switchable in the interface. Reusable prompt templates can be saved as skills in ~/.flux/skills/ and invoked as slash commands. The code_explorer and bug_investigator sub-agents handle focused codebase tasks. The --yolo and --max-turns options enable non-interactive workflow runs such as CI jobs. A static binary installer detects macOS or Linux architecture without a build toolchain. Source builds list Go 1.26.1 or later, Git, Python 3, and ripgrep as prerequisites. Flux is MIT licensed.

Who it suits

Flux suits developers who work in a shell and want AI assistance with codebase exploration, file changes, commands, and model choice. It also fits CI workflows needing non-interactive runs.

What it does well

Free and MIT licensed
Terminal TUI with model switching and diffs
Reads, writes, searches, and runs shell commands
Supports three listed AI providers
Headless options for workflow automation

What to know first

Available on Linux and macOS only
Requires provider API keys
Source builds require listed prerequisites
No IDE support is stated

Verdict

Flux packages codebase-aware AI assistance, terminal controls, reusable skills, and headless execution in a free open-source tool. Its Linux and macOS focus and provider-key setup are important considerations for adoption.

Facts from flux's own pages

Coding agent: Yes · fluxagent.dev, 22 Sept 2026
AI providers: Flux supports OpenRouter, OpenAI, and Anthropic, and lets users switch models while working. · fluxagent.dev, 12 Oct 2026
API keys: The setup instructions accept OpenRouter, OpenAI, or Anthropic API keys through environment variables. · fluxagent.dev, 12 Oct 2026
CI use: Flux supports non-interactive headless runs with --yolo and --max-turns for workflow tasks. · fluxagent.dev, 12 Oct 2026
Codebase indexing: Yes · fluxagent.dev, 22 Sept 2026
Headless use: The --yolo and --max-turns options let Flux run non-interactively in workflow steps. · fluxagent.dev, 12 Oct 2026
Installation: The site describes a single static binary installer for macOS and Linux that detects OS and architecture and needs no build toolchain. · fluxagent.dev, 12 Oct 2026
Intended users: The maker presents Flux for people who work in a shell and describes CI workflows such as nightly dependency updates and documentation sync as use cases. · fluxagent.dev, 12 Oct 2026
License: The product site identifies Flux as MIT licensed. · fluxagent.dev, 12 Oct 2026
Model providers: Flux supports OpenRouter, OpenAI, and Anthropic, and lets users switch models in the interface. · fluxagent.dev, 12 Oct 2026
Parallel work: Flux can run independent tool calls in parallel when safe. · fluxagent.dev, 12 Oct 2026
Prerequisites: The repository's source-build instructions list Go 1.26.1 or later, Git, Python 3, and ripgrep as prerequisites. · github.com, 12 Oct 2026
Product: Flux is a terminal-based AI coding assistant built with Go and tuix. · fluxagent.dev, 12 Oct 2026
Reusable skills: Users can add reusable prompt templates as skills in ~/.flux/skills/ and invoke them as slash commands. · fluxagent.dev, 12 Oct 2026
Security-related capability: The GitHub repository lists secret detection and redaction among its code components. · github.com, 12 Oct 2026
Sub-agents: It includes code_explorer and bug_investigator sub-agents for focused codebase tasks. · fluxagent.dev, 12 Oct 2026
Supported IDEs: none stated; terminal TUI · fluxagent.dev, 22 Sept 2026
Terminal access: Yes · fluxagent.dev, 22 Sept 2026
Terminal interface: Its keyboard-driven TUI includes slash commands, a model switcher, file diffs, and a live status bar. · fluxagent.dev, 12 Oct 2026
Workspace tools: Its tools can read and write workspace files, search code, find files, and run shell commands. · fluxagent.dev, 12 Oct 2026

Where flux stands on Freedom251

AI Coding Assistants#81 of 102