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system-one-playground

SysOneScript language, Go System One client, semlint semantic code checks and a VS Code Studio for building with Jev judgments.

LibrarybetaMIT
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Overview

System One Playground is a toolkit for building readable scripts and developer tools on top of the TypeSafe System One API. It includes SysOneScript (SOS), a small scripting language with a CLI, language server, formatter, debugger and native build, a Go client module for calling the API directly, semlint for semantic code checks, and a VS Code extension called Studio.

The design is offline-first: canonical scripts run without any key, and only model-backed Jev operations need TYPESAFE_API_KEY and can make paid provider requests. Examples include a semantic gauntlet that stress-tests Jev with eight decisions. It targets developers who want to mix ordinary scripting with Jev judgments or call Jev from Go. SOS is a preview: remote package resolution and a plain JavaScript emitter are not implemented, and live Jev host adapters for browser or WASI are not available.

What the decision model decides

TypeQuestionAnswers
OtherScript-defined Jev judgments (choice, score or noul) over text or code(inferred)—
Yes / noDoes this code violate a semantic rule? (semlint)(inferred)—

How it works

  1. Write an SOS script or Go program; run it offline first.
  2. Add Jev judgment operations and set TYPESAFE_API_KEY.
  3. The runtime calls the System One API and returns typed answers.
  4. Script logic acts on the answers, or semlint reports semantic findings.

Strengths

  • Scripts run offline until a judgment is needed, so cost is limited to model calls.
  • Single installer for CLI, plus a VS Code extension with bundled runtime.
  • Go client usable on its own via go get.

Caveats

  • SOS is a preview with several features unimplemented.
  • Model-backed operations depend on TypeSafe's hosted API.
  • Not an official TypeSafe SDK.

Getting started

curl -fsSL https://github.com/DonaldMurillo/system-one-playground/releases/download/vscode-v0.5.1/install.sh | sh, then sysone run hello.sos.

At a glance

Type
Library
Status
beta
Language
Go
Runtime
CLI + VS Code extension
Has code
yes
License
MIT

Use cases and integrations

How curated lists describe it

Frequently asked questions

What is SysOneScript?

A small scripting language with its own CLI and editor tooling where Jev judgments are built-in operations.

Do I need a TypeSafe key?

Only for model-backed Jev operations; ordinary scripts run offline without one.

Can I use just the Go client?

Yes, install github.com/DonaldMurillo/system-one-playground/typesafe with go get.

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