v1.0.0-beta.4

🚀 Host Your RPC Anywhere

Until now, Serde.FS relied on the source-generated entry point (via [<Serde.FS.EntryPoint>]) to register generated JSON codecs and RPC client factories at startup. That worked great — until your API assembly was hosted by a process that never runs your entry point: a desktop shell embedding Kestrel in-process, a WebApplicationFactory integration test, an AutoCAD/Revit add-in, or a C# host referencing your F# API assembly as a library.

As of beta.4, registration happens at the point of use. No entry-point ceremony required.

✨ What's New

• MapRpcApi self-initializes. On first call it discovers and runs the generated bootstraps (JSON codecs + RPC dispatch) for the relevant assemblies. In-process Kestrel hosts, test hosts, and add-ins now just work.
• RpcClient.create self-initializes. On a factory miss it runs the bootstrap scan (interface's assembly first, then all loaded assemblies) before failing.
• New public escape hatch: Serde.FS.Bootstrap. For cases where you need registrations before the first RPC call (e.g. standalone SerdeJson.serialize during startup):

Serde.FS.Bootstrap.Run()                        // scan all loaded assemblies
Serde.FS.Bootstrap.Run(typeof<MyApi>.Assembly)  // target one assembly (Init failures propagate)

Idempotent and thread-safe — each generated bootstrap runs at most once per process, no matter how many times or from how many threads it's invoked.

🔧 Fixes & Internals

• SerdeJson.registerCodecs now merges into the global codec registry (under a lock) instead of rebuilding it from scratch. Previously, if two assemblies both carried generated codecs, the second registration silently wiped the first. Registrations remain last-write-wins per type, so single-assembly behavior is unchanged.
• The generated entry point is now three lines. Instead of inlining its own reflection scan, it simply calls Serde.FS.Bootstrap.Run() — one scan implementation, one idempotency tracker, shared by every host style.

📌 Notes

• [<Serde.FS.EntryPoint>] is still recommended for apps that serialize outside RPC before the first MapRpcApi / RpcClient.create call.
• All packages ship in lockstep at 1.0.0-beta.4: Serde.FS, Serde.FS.Json, Serde.FS.AspNet, Serde.FS.Fable.
• No breaking changes — existing apps using the generated entry point behave exactly as before.

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This release was motivated by (and battle-tested in) the fable-lit-fullstack-template's new cross-platform desktop host,
which runs the same ASP.NET Core + Fable.Lit app in a native window via in-process Kestrel — with zero bootstrap code.