Installation

Zasper is a single binary of about 8 MB with no runtime dependencies. It runs a server on your own machine, and you use it in your browser: Chrome, Firefox, Safari or Edge.

Requirements

• A Jupyter kernel. Zasper runs notebooks on Jupyter kernels but does not install one. pip install ipykernel is enough to get started; Installing Jupyter Kernels covers other languages. Without a kernel Zasper still starts, and the Launcher tells you what to install.
• A modern browser.

Homebrew (macOS)

brew install zasper-io/tap/zasper

Snap (Linux)

sudo snap install zasper

Conda

conda install zasper -c conda-forge

Prebuilt Binaries

Download the archive for your platform from the Downloads page or from GitHub Releases, unpack it, and put zasper somewhere on your PATH:

tar -xzf zasper-webapp-1.0.0-linux-amd64.tar.gz
sudo mv zasper /usr/local/bin/

Every release carries a checksum file. To verify what you downloaded, run this in the folder that has both:

sha256sum -c zasper_1.0.0_checksums.txt --ignore-missing      # Linux
shasum -a 256 -c zasper_1.0.0_checksums.txt --ignore-missing  # macOS

The macOS binaries are signed and notarized by Apple, so Gatekeeper opens them without a warning.

Check That It Works

zasper --version

This prints 1.0.0. Then start Zasper in the folder you want to work in:

cd ~/notebooks
zasper

and open http://127.0.0.1:8048.

Platform Support

The Linux archives are static binaries, so one build works on every distribution, Debian and Red Hat alike.

Upgrading from 0.2.0-beta

1.0.0 is the first stable release. From here on, Zasper’s HTTP and WebSocket API, its configuration file and its command-line flags follow semantic versioning and will not break within 1.x. A few things changed on the way there:

• The server binds 127.0.0.1 by default instead of every interface. If you reach Zasper from another machine, start it with --host=0.0.0.0 and turn on --protected=true at the same time; see Deploying on Cloud.
• The desktop app is gone. Zasper is now only the local server you open in a browser. Install it with any of the methods above.
• DELETE /ws/kernels/{kernel_id} has been removed. Use DELETE /api/kernels/{kernelId}, which is unchanged.
• Kernel connection files have moved from the system temp directory to ~/.zasper/runtime. They are now readable only by you and are deleted when the kernel stops.
• Zasper sends anonymous usage data unless you turn it off. See Configuration for what is sent and how to stop it.

The full list is in the changelog.

Troubleshooting

zasper: command not found

The folder you put zasper in is not on your PATH. For Homebrew, snap or conda, check that the package manager itself is on your PATH.

A kernel doesn’t show up

Run jupyter kernelspec list to confirm the kernel is registered, then restart Zasper. Kernels installed while it is running are picked up on the next start.

Zasper can’t be reached from another machine

By default Zasper binds only 127.0.0.1. See Deploying on Cloud.

Something else is wrong

Zasper logs to standard output, not to a file. Run it from a terminal with --debug to see more:

zasper --debug

If that doesn’t explain it, open an issue with that output.