Sluice

Six requests for the same tree: one run, five coalesced, and a repeat served from the cache.

Sluice runs each gate (tests, linters, type checks) once per git tree, under a global concurrency budget, and caches the result. Git hooks call sluice run; coding agents call the MCP server started by sluice mcp.

Why

You run four coding agents on the same project, each in its own git worktree, and every one of them triggers the same pre-commit and pre-push checks. Four copies of the full suite run at once and the machine stops answering. Most of those runs verify a tree that already passed: the agent ran it, then pre-commit, then pre-push, then again after a no-op rebase. Hooks live in the shared .git/hooks, so nothing coordinates the worktrees. And an agent's shell tool has a timeout, so a hook that waits in a queue inside git commit makes the agent move on without the result. Sluice bounds the concurrency, removes the redundancy and never leaves an agent hanging.

Features

• Per-tree cache. The key is the exact content of the working tree plus the gate definition, shared by every worktree. Hits return in milliseconds and never need the daemon.
• Daemon with budget and coalescing. A per-user daemon runs gates under a weighted budget; identical simultaneous requests share one run.
• PSI and memory admission. New work is held while the machine is under real pressure (Linux PSI), and a gate starts only when the memory it is expected to use (learned from its earlier runs) fits what is free.
• Git hooks for Husky, lefthook, pre-commit/prek and plain .githooks/, failing fast inside agents instead of hanging.
• MCP tools and an agent plugin. sluice mcp gives agents a blocking verify tool; the agent plugin adds a skill, a guard hook and a session hook that puts shell shims in the agent's PATH and hands it the rules. Install it and nothing else.
• sluice exec and queue-only gates put any command (docker build, make) under the same budget, without cache.
• Path-scoped gates key on part of the tree, so unrelated changes keep the cached pass.
• Local merge queue. Agents enqueue committed branches; a human approves one atomic landing. The train's worktree can be prepared ([queue] prepare, for example a dependency install) before its gates run.
• sluice doctor and sluice update check the installation (with a redacted bug-report bundle) and upgrade in place.

Install

Linux only, with git 2.31 or newer in PATH. Prebuilt static binaries for x86_64 and aarch64 are on the releases page.

curl -fsSL https://raw.githubusercontent.com/josegarridodigio/sluice/main/scripts/install.sh | sh

This installs the latest release into ~/.local/bin (SLUICE_VERSION pins a tag, SLUICE_INSTALL_DIR relocates). Later, sluice update upgrades in place, checksum-verified. From source, with a stable Rust toolchain:

cargo install --path crates/sluice-gate

The crate is sluice-gate because sluice is taken on crates.io; the binary is sluice.

Quick start

1. Install the binary (above).

2. Install the agent plugin, in Claude Code (with sluice in your PATH):

   /plugin marketplace add josegarridodigio/sluice
   /plugin install sluice@sluice
   

3. Run sluice init in each repository (or let the agent propose it):

   sluice init --dry-run        # detects the stack and your hooks; shows, writes nothing
   sluice init                  # writes .sluice.toml, rewires your hooks
   

That is all: no PATH edit, no CLAUDE.md, no user config. From then on a commit runs sluice run on a cache miss, and sluice status shows the daemon, budget, queue and totals. Agents other than Claude Code use the MCP server and, if they only have a shell, sluice shim install (agents).

A gate is a named shell command in .sluice.toml:

version = 1

[gates.test]
cmd = "npm test -- --maxWorkers=2"
weight = 4
hooks = ["pre-commit", "pre-push"]

Run sluice run test twice on the same tree and the second call returns from the cache. Recipes for Node, Python, Rust, Go, Docker and monorepos are in the gates cookbook.

Documentation

Status and limitations

Sluice is alpha: complete enough for early adopters, not yet proven by long use. The gaps you will hit first:

• Linux only, git 2.31 or newer; other platforms are not planned.
• Verdicts, not artifacts. A hit says a gate passed on this tree; it does not restore build outputs.
• Queueing covers declared gates, sluice exec and the heavy command list. In agent sessions the plugin's guard and shims queue the heavy commands; a command run by absolute path, under env -i or from a shell that resets PATH bypasses the queue. Since 0.5.0 such commands are still contained (cgroups) when containment is available, and your forge's branch protection remains the enforcement for what lands.
• Containment needs cgroup v2 and a systemd user manager. CPU weights need systemd 252 or newer (or an administrator's drop-in); the memory policy needs systemd-oomd and systemd 257 or newer, otherwise the agents' memory is only accounted (gate jobs are still admitted by memory and are the kernel's preferred OOM victims; the opt-in [admission] memory_guard covers machines without systemd-oomd). In containers, on cgroup v1 or without a user manager Sluice runs uncontained and sluice doctor says why. It protects against accidental overload, not against a process that moves itself out.
• 0.5.0 containment was validated on two Ubuntu 26.04 machines (20 and 12 threads), with real agent sessions on the command line and over SSH. Not yet validated: the agent's Bash sandbox with its default seccomp filter (tested only with sandbox.network.allowAllUnixSockets), the interactive terminal UI, IDE integrations, and systems with systemd older than 257. Reports are welcome.
• Shims need the agent plugin or setup by hand. Claude Code gets them automatically; other agents need sluice shim install and a PATH entry. A .sluice.toml with weight = "auto" needs 0.4.0.
• A hit is a local optimisation. CI stays authoritative, and inputs git cannot see must be declared (key_inputs, key_files).
• Per-worktree caches. Tools that keep state inside the checkout, such as node_modules/.cache, need one copy per worktree.

The full list is in the final report.

Contributing

Issues and discussions are open; use the issue forms (a bug report asks for sluice doctor --bundle). The quality bar is in CONTRIBUTING.md.

License

MIT. See LICENSE.