Weaver

A human-friendly, agent-native semantic command-line tool.

Weaver is your AI agent's best friend when it comes to understanding and modifying code. We believe the shell should speak the language of semantics—not just bytes and lines—so we've built a tool that brings deep code intelligence to your terminal.

What is Weaver?

Weaver is a Rust-based CLI tool that provides semantic operations on codebases through a simple, composable interface. It follows the UNIX philosophy: small, focused tools that communicate clearly and play nicely with existing shell utilities like jq, xargs, and find.

Under the bonnet, Weaver runs a daemon (weaverd) that orchestrates language servers, syntax analysers, and specialized plugins—all sandboxed for safety—while the lightweight CLI (weaver) lets you issue commands and stream results. Whether you're an AI agent planning a refactor or a human debugging a tricky rename, Weaver gives you the semantic primitives you need.

Status

Weaver is in active early development before the first v0.1.0 release. The repository already contains the CLI/daemon architecture, shared configuration, Language Server Protocol (LSP) hosting, Tree-sitter syntax support, graph and card foundations, plugin infrastructure, sandboxing, and write-operation safety harness work. The public command surface is now being reset around ADR 007, which makes the 0.1.0 target human-friendly and agent-native without preserving compatibility with the prototype observe / act / verify grammar.

Check the roadmap for the current build sequence and the user's guide for the split between current prototype commands and the 0.1.0 target contract.

Key features

• Semantic operations as shell verbs — Current prototype commands expose code intelligence today; the 0.1.0 target moves to resource-first commands such as definitions get, references list, and symbols rename.
• Agent-native output contracts — The target surface keeps readable human defaults while making --json the stable machine-readable path.
• Multi-layer fusion — Combines Language Server Protocol (LSP), Tree-sitter parsing, and call graph analysis for comprehensive code understanding.
• Zero-trust sandboxing — External tools run in isolated environments using Linux namespaces and seccomp-bpf filters.
• Graceful degradation — When a capability isn't available, Weaver tells you what's missing and suggests alternatives.

Components

Weaver is organized as a Cargo workspace with dedicated crates for the CLI, daemon, configuration, LSP hosting, syntax parsing, graph support, cards, plugins, sandboxing, Sempai query planning, build utilities, and end-to-end tests. See the repository layout for the current crate map and planned component ownership.

Getting started

Here's the quickest path to your first Weaver command:

# Start the daemon
weaver daemon start

# Query a symbol definition
weaver definitions get --uri file:///path/to/main.rs --position 42:17

# Check daemon status
weaver daemon status

# Stop the daemon when you're done
weaver daemon stop

For full installation, configuration, and usage instructions, please see the User's Guide. It covers daemon lifecycle management, configuration layering, and the complete command reference.

Building from source

Weaver requires the pinned Nightly Rust toolchain nightly-2026-03-26 for local builds. The workspace .cargo/config.toml uses options that require the Nightly toolchain, so stable Rust is not sufficient for local Cargo builds in this checkout. To build:

cargo +nightly-2026-03-26 build --release

To run the test suite:

cargo +nightly-2026-03-26 test --workspace

Toolchain prerequisites

The workspace .cargo/config.toml enables Nightly-only build settings for the Cranelift codegen backend in development builds. Install the pinned toolchain and component with:

rustup toolchain install nightly-2026-03-26
rustup component add rustc-codegen-cranelift --toolchain nightly-2026-03-26

Set a local override so Cargo uses that pinned Nightly automatically in this checkout:

rustup override set nightly-2026-03-26

If any of these prerequisites are missing, the failure mode is often opaque: Cargo may report unstable -Z option errors or missing rustc-codegen-cranelift. When that happens, verify the pinned Nightly toolchain and the Cranelift component first.

If local builds fail, verify the pinned Nightly override first, then confirm the Cranelift component is installed before investigating the workspace itself.

Documentation

• User's Guide — Configuration, daemon lifecycle, and command reference
• Design Document — Architecture, philosophy, and technical deep-dive
• Roadmap — Development phases and upcoming features

Licence

Weaver is released under the ISC License.