json-everything

json-everything (by Greg Dennis) is a suite of ~40 System.Text.Json-based NuGet packages covering "all of your JSON needs" — including JsonSchema.Net (JSON Schema validation, drafts 6 through 2020-12), JsonPath.Net (RFC 9535), JsonPatch.Net (RFC 6902), JsonPointer.Net (RFC 6901), JsonLogic, Json.More.Net, JsonSchema.Net.Generation, Yaml2JsonNode, and OpenAPI / data-annotations / ASP.NET validation helpers. The project is MIT-licensed and a .NET Foundation member.

On 15 January 2026 (json-everything#981, blog: Why Is Everything So Expensive?!) Greg Dennis announced that json-everything is adopting the Open Source Maintenance Fee (OSMF) model, effective 1 February 2026.

What Changed

The source stays MIT. Greg Dennis explained the motivation bluntly — despite 140+ million downloads, voluntary sponsorship had produced only two or three sponsors:

"I've spent the past 15 years building open source software in my spare time … all of it completely free."

What changed: an EULA is attached to the binary releases (the packages on NuGet.org and GitHub) requiring revenue-generating organizations to pay a monthly maintenance fee. This applies across all package families in the repository. As with NPOI, you can still read, fork, and build the source under MIT — the obligation rides on the official compiled packages.

No build-time enforcement tooling has been announced (contrast Verify, which added a SponsorCheck build step).

Who Pays and How Much

Paid via GitHub Sponsors. The base Maintenance Fee is $10/month for anyone with annual gross revenue of at least US $10,000 who uses the project in revenue-generating activity. Optional size-based tiers:

• Maintenance Fee (Small Org) — fewer than 20 employees: $10/month
• Maintenance Fee (Medium Org) — 20–100 employees: $25/month
• Maintenance Fee (Large Org) — more than 100 employees: $50/month
• Grateful User — $5/month, voluntary, any sponsor

Exempt: individuals, hobbyists, students, and any organization that does not generate revenue using the libraries — though voluntary sponsorship is encouraged.

Note: GitHub Sponsors does not offer annual billing for this account; annual payers use a one-time payment and are responsible for renewal.

What This Means For You

• Individual / non-revenue / under $10k: no fee. Voluntary "Grateful User" sponsorship welcomed.
• Revenue-generating organization over $10k: sponsor gregsdennis at the base $10/month (or a size tier), for any number of json-everything packages.
• Want to avoid the obligation: pin every json-everything package to a version released before 1 February 2026 (those have no EULA), or evaluate alternatives per feature area.

Alternatives

json-everything is really many libraries; there is no single replacement. Match the alternative to the feature you use.

JSON Schema (JsonSchema.Net)

1. NJsonSchema — MIT. Schema validation plus C#/TypeScript code generation.
   • Pros: free, mature, strong codegen story (feeds NSwag).
   • Cons: built on Newtonsoft.Json; draft coverage lags the latest specs.
2. Newtonsoft.Json.Schema — commercial (free under 1,000 validations/hour). Not an open-source escape hatch.
3. Pin JsonSchema.Net to a pre-February 2026 release.

JSON Path (JsonPath.Net)

• JsonCons.JsonPath — MIT, System.Text.Json-based, RFC-aware JSONPath.
• Hyperbee.Json — Apache-2.0, JSONPath and JSONPointer on System.Text.Json.

JSON Patch (JsonPatch.Net)

• Microsoft.AspNetCore.JsonPatch — first-party (MIT). Historically Newtonsoft-based; a System.Text.Json implementation ships with .NET 10.
• Hyperbee.Json — also implements JSON Patch.

JSON Pointer (JsonPointer.Net)

• Hyperbee.Json or JsonCons — both MIT/Apache-2.0 with JSON Pointer support. Pointer is a small spec and is also ~100 lines to implement directly.

YAML → JSON (Yaml2JsonNode)

• YamlDotNet (MIT) can deserialize YAML directly; a short adapter converts its node model to JsonNode.

Conclusion

json-everything's source stays MIT, but every package released from 1 February 2026 carries an OSMF EULA requiring revenue-generating organizations above $10k to pay from $10/month via GitHub Sponsors — one fee for the whole suite. Individuals and non-revenue users are exempt. Teams that would rather not engage can pin pre-February-2026 versions or swap in MIT/Apache alternatives such as NJsonSchema, JsonCons.Net, Hyperbee.Json, or the first-party ASP.NET JSON Patch package, feature by feature.

Links and References

• GitHub Issue: Introduction of a maintenance fee (json-everything#981)
• Blog: Why Is Everything So Expensive?!
• GitHub: json-everything/json-everything
• Website: json-everything.net
• GitHub Sponsors: gregsdennis
• Open Source Maintenance Fee: Home · For Consumers
• Alternative: NJsonSchema
• Alternative: JsonCons.Net
• Alternative: Hyperbee.Json
• Similar model: Verify · Polly · NPOI