.NET · Open Source

Arkadiusz Biel

I build open-source .NET infrastructure — the parts of a system that live between services. Currently: AsyncAPI & Arazzo tooling, persistent queues, and .NET Aspire extensions.

Flagship

The bulk of my current work — bringing the OpenAPI developer experience to the specs that describe everything else.

Bielu.AspNetCore.ApiDescriptions →

Code-first AsyncAPI, Arazzo and Overlay document generation for ASP.NET Core, from minimal or controller-based APIs — the same experience Microsoft.AspNetCore.OpenApi gives you for REST, applied to event-driven and workflow specifications.

Core
Bielu.AspNetCore.AsyncApi .Attributes .Extensions .Versioning .Merger
Protocol bindings
SignalR · gRPC · Server-Sent Events · WebRTC
Interactive UI
.Scalar with SignalR, gRPC and Aspire variants
Workflows & overlays
Bielu.Arazzo.NET Bielu.Overlay.NET Bielu.AspNetCore.Arazzo
Tooling
CLI · dotnet new templates · build-time document generation

Messaging & infrastructure

Durable delivery, orchestration and secrets — the plumbing under distributed .NET systems.

Libraries & developer tooling

Smaller pieces that keep the rest of the ecosystem consistent.

Upstream contributions

I don't just consume these specs — I help build the tooling and the specs themselves.

scalar/scalar
Drove AsyncAPI support into Scalar — document-wide auth rendering, protocol bindings, broker security schemes, and AsyncAPI 3.1 mocking over WebSocket & SSE. Also contributed the Azure Functions and AWS Lambda .NET integrations, a URL-loadable plugin system, and repo-wide Central Package Management.
ByteBardOrg/AsyncAPI.NET
Deserialization validation and spec-conformance fixes to the official continuation of LEGO.AsyncAPI.NET.
OAI/Overlay-Specification
Proposed target document format declaration (targetFormat) so Overlay can address non-OpenAPI documents.

Elsewhere

Conference speaker (Umbraco Poland Festival & others) and Arctic Code Vault contributor. Earlier work covered search & indexing and the Umbraco ecosystem — those packages remain on NuGet, but are no longer actively developed.