Installation

Outcall is a Linux-only daemon. It manages a kernel network bridge and applies nftables rules — both require Linux. macOS hosts can build the workspace and run the CLI, but outcalld itself will not start outside Linux.

Fast install

Install the release binaries:

curl -fsSL https://outcall.dev/install.sh | sh

On Linux, the installer also preloads the matching outcalld Docker image when Docker is available, so the first outcall start run can start from local release artifacts instead of relying on an initial registry pull.

Then, from the root of the project you want to isolate:

outcall
outcall start

Running bare outcall prints the recommended first command for the current project and host.

If Outcall cannot infer the provider cleanly, choose one explicitly:

outcall claude
outcall codex

outcall start is the shortest supported first-run path when the host only has one supported provider configured. It expands to the same flow as outcall claude / outcall codex: outcall run <recipe>, which scaffolds .outcall/, checks likely auth/config sources, builds the recipe image, starts outcall-daemon if needed, creates the default network if needed, verifies the recipe entrypoint in a smoke container, and then launches the real isolated agent container.

If the first run stops on a prerequisite, inspect it directly with:

outcall doctor claude
outcall doctor codex

Requirements

The daemon does not need root if it has the capabilities above. In practice, running it as a Docker container with --cap-add and --network host is the recommended path.

Kernel prerequisite — br_netfilter

Threat T-2 (agent-to-agent isolation) is enforced by the nftables FORWARD chain. The chain only sees L2 bridge traffic if the br_netfilter kernel module is loaded and net.bridge.bridge-nf-call-iptables=1. Without it, two containers on the same bridge can reach each other directly at L2 and T-2 silently fails.

The daemon attempts to flip the sysctl on startup, but loading the module itself requires CAP_SYS_MODULE — which the recommended container deploy does not grant. Load the module on the host before starting the daemon:

# One-shot for the current boot
sudo modprobe br_netfilter
sudo sysctl -w net.bridge.bridge-nf-call-iptables=1
sudo sysctl -w net.bridge.bridge-nf-call-ip6tables=1

# Persist across reboots
echo br_netfilter | sudo tee /etc/modules-load.d/outcall.conf
sudo tee /etc/sysctl.d/99-outcall.conf <<'EOF'
net.bridge.bridge-nf-call-iptables = 1
net.bridge.bridge-nf-call-ip6tables = 1
EOF

Verify after boot:

lsmod | grep br_netfilter
cat /proc/sys/net/bridge/bridge-nf-call-iptables   # → 1

If you cannot enable br_netfilter (locked-down kernel, hardened host), treat T-2 as out of scope and put each agent on its own outcall-managed network — bridge separation gives you isolation without relying on FORWARD.

Manual daemon launch

docker run -d --rm \
  --name outcall-daemon \
  --network host \
  --cap-add NET_ADMIN \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -v /tmp/outcall:/tmp/outcall \
  -v /etc/outcall:/etc/outcall \
  ghcr.io/outcall-dev/outcalld:latest \
  --bridge outcall0

The image contains outcalld, outcall, and outcall-agent on PATH. For local development you can still build the debug image from source with docker build -f Dockerfile.test -t outcall-daemon ..

Required mounts:

Install from source

Linux:

git clone https://github.com/outcall-dev/outcall.git
cd outcall
cargo build --workspace --release
sudo install -m 0755 target/release/outcalld /usr/local/sbin/outcalld
sudo install -m 0755 target/release/outcall  /usr/local/bin/outcall
sudo install -m 0755 target/release/outcall-agent /usr/local/bin/outcall-agent

A systemd unit, sysctl knobs, and capability defaults will ship with a future package release; for now run the daemon under your service manager of choice.

Verify the install

outcalld --version
outcall  --version
outcall-agent --version

Then start the daemon and check the bridge is up:

sudo outcalld --bridge outcall0 &
outcall bridge status
# Bridge:    outcall0
# Status:    up
# Index:     12
# nftables:  active

If the CLI reports cannot connect to outcalld at … — is it running?, check the socket path (/tmp/outcall/host.sock) and the daemon's permission to bind it.

Next steps

• Quickstart — isolate Claude Code or Codex in one project.
• Configuration — every daemon flag explained.
• Writing rules — the rule YAML format and matchers.