jPipe is a language and toolchain for justification diagrams: structured arguments that connect a top-level claim (“version 2.0 is ready to ship”) down to the sub-claims, strategies, and evidence that support it. You write a model in a small textual language (a .jd file), and jPipe renders it as a diagram you can read and review, then later execute against real data to check that the argument still holds.

The jPipe compiler is the starting point; the VS Code extension and the runner both build on it

This section takes you from a blank editor to your first justification. Before you install anything, here is the map of the tools you will meet.

The three tools

Tool What it does When you need it
jPipe Compiler The jpipe command-line tool that parses, validates, and renders models. Everything else in jPipe runs on top of it. Start here: one package-manager command.
jPipe IDE A Visual Studio Code extension to author .jd files, with syntax highlighting, a live diagram preview, and one-click export. Install it second. It finds the compiler on its own.
jPipe Runner The jpipe-runner tool that turns a justification into an executable check against real data. When you want the argument verified automatically, typically in CI/CD.

Where to start

One command installs the compiler, and it brings Java and Graphviz with it: our Homebrew, APT and Scoop packages declare both as dependencies, so you never chase a runtime by hand. The extension then picks that compiler up with no configuration at all, because it looks for a jpipe on your PATH out of the box.

  1. Install the compiler: brew, apt or scoop, one line.
  2. Install the IDE: the extension, with nothing to configure.
  3. jPipe 101: write, preview, and export your first justification.

Locked-down machine, no package manager, or a project pinned to a specific compiler version? The extension can download and manage a compiler itself: see IDE execution modes.

Going further

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