1. curve-solver
    haiilong.github.io/curve-solver ↗

    Built for Desmos. Given a list of points, it solves them exactly (linear, quadratic, cubic, circle for 3 points, general conic for 5) or approximates them (sine, log, exponential, or axis-aligned ellipse). Copy-paste helpers move points and equations straight between the page and Desmos.

  2. calculus-walkthrough
    haiilong.github.io/calculus-walkthrough ↗

    O/A level calculus solver. Each step shows the rule that was applied and the expression before and after it.

  3. SingletonJob
    https://www.nuget.org/packages/SingletonJob/ ↗

    Lightweight Redis-backed singleton background jobs for multi-instance .NET deployments.

  4. CloudHttp
    https://www.nuget.org/packages/haiilong.http.extensions/ ↗

    Cloud-friendly HttpClient extensions for .NET: independent connection pools for one upstream, cloud-tuned SocketsHttpHandler defaults, and composition with Microsoft.Extensions.Http.Resilience.

  5. boostexport
    github.com/haiilong/boostexport ↗

    Export LightGBM, XGBoost, and CatBoost models for native inference in .NET and Go - no Python runtime needed.