// Comments are allowed
{
    "FOO": [1, 2, 3,], // trailing comma in an array
    BAR: 42,           // unquoted property name
    "BOZ": 24,         // trailing comma in an object
}
/* block comments
   are supported as well */

Fixes annoying problems with manually-written JSON in Go:

• lack of trailing commas,
• lack of comments.

We also support bare property names. You can use those for convenience, but the primary motivation is that if you feed JSON through one of those newfangled modern JS formatters, they will often unquote the keys, which is very annoying in some cases.

Why this library: it's a tiny JSON preprocessor, allowing to use standard encoding/json. No code duplication, no missing features (e.g. DisallowUnknownFields), no surprises, smooth upgrade path to JSON v2 (won't even require any changes here).

Install:

go get github.com/andreyvit/jsonfix

Use:

json.Unmarshal(jsonfix.Bytes(source), whatever)

We preserve line numbers when preprocessing.

We accept contributions that:

• add better documentation and examples;
• add more tests;
• improve handling of invalid JSON (we don't know any problems so far, but it hasn't been a huge focus so far);
• implement single-quoted strings (one could make a case similar to bare keys here, if widespread formatters start preferring single quotes);
• fix bugs.

Out of scope (unless you convince us otherwise):

• multiline strings
• unquoted string values
• the rest of JSON5

We recommend modd (go install github.com/cortesi/modd/cmd/modd@latest) for continuous testing during development.

Maintain 100% coverage. It's not often the right choice, but it is for this library.

• 1.1.0 (2025-01-27): Added bare keys and block comments.

• 1.0.0 (2023-04-04): Initial release supporting trailing commas and line comments.

Copyright (c) 2023–2025 Andrey Tarantsov. Published under the terms of the MIT license.