Welcome to the JSON Logic Community! Our mission is to foster collaboration among maintainers and users of JSON Logic implementations across platforms to develop a more rigorous specification, promote compatibility, and provide resources that make JSON Logic more robust and beneficial to everyone.

Many productivity applications require a way to serialize and define filters and sandbox application capabilities, and many folks end up rolling their own implementations.

JSON Logic has become a reasonably well-used standard for expressing conditional logic in a portable & embeddable format.

With time, inconsistencies and ambiguities have emerged between different implementations, making it challenging for developers to rely on JSON Logic across platforms.

Developing a standard specification and robust test suite will ideally make JSON Logic easier to adopt; and empower developers further.

1. Develop a Rigorous Specification

• Address ambiguities and inconsistencies in the current spec.
• Define behaviors for edge cases (e.g., truthiness, accessing empty keys and keys with separators in them).

2. Build Compatibility Resources

• Create and maintain a compatibility table for implementations.
• Provide a robust test suite for maintainers to validate their projects.

3. Support JSON Logic Maintainers

• Offer resources and community support to help resolve implementation differences.
• Facilitate collaboration between maintainers to align on common goals.

4. Improve AST Use Cases

• JSON Logic is a surprisingly solid & minimal AST; we should enable that!
• By exploring it as an AST, it could become a solid back-end for future specifications or embedded grammars.

5. Encourage Extensibility

• Identify and spec out common extensions.
• Release shared libraries or guidelines for extending JSON Logic.

Here are some examples of challenges we’re working on:

• Accessing keys like { '': 1 } or { 'hello.world': 1 }.
• Truthiness quirks, such as { "!": [0] } vs { "!": 0 }; and { "!": { "var": "data" } }, where data is an array.
• Handling iterator contexts (e.g., accessing parent context in filter operations).
• Defining behaviors for .length and similar properties in var operations. (a length operator is likely preferable)
• Aligning on reserved operators and backwards-compatible extensions.
• How to embed data in logic, and what is interpreted as data vs logic.
• There also just tend to be quirks between different implementations (auto-flattening of arrays, single-argument parameters)

We believe in the power of open collaboration! Here's how you can contribute:

1. Join the Conversation

• Participate in discussions to shape the specification and resolve ambiguities.

2. Submit Feedback

• Share issues, quirks, or use cases you've encountered with JSON Logic.

3. Contribute to Resources

• Help build the compatibility table or improve the test suite.

4. Later on, participate in extension discussions

Whether you’re a project maintainer, developer, or JSON Logic enthusiast, we’d love to have you onboard!

We'd also love to have volunteers willing to adopt abandoned implementations.

• Jeremy Wadhams for inventing JSON Logic
• The OpenFeature Team as one of the biggest public users of cross-library JSON Logic, and for their willingness to back this initiative
• Adam Parry for the Vulcan Salute used in the JSON Logic logo