xapi-dotnet

Experience API (xAPI 2.0 / IEEE 9274.1.1, and 1.0.3) for .NET: models and validation, an async LRS client with a durable outbox, and a Learning Record Store you can embed in an ASP.NET Core app.

Status: 0.x. 0.3.0 is on NuGet and the LRS image is on ghcr.io. The API can change between minor versions until 1.0; the 1.0 milestone lists what is left. Documentation: https://nurullahturkoglu.github.io/xapi-dotnet/

The 2.0 standard is IEEE 9274.1.1-2023, also adopted as ISO/IEC/IEEE 39274-1-1:2025.

Packages

Package	What it is	Targets
Xapi.Core	Statement model, strict JSON reading and writing for 1.0.3 and 2.0.0, validation, statement comparison	netstandard2.0, net10.0
Xapi.Client	Async client for every LRS resource, version negotiation, attachments, statement signing	netstandard2.0, net10.0
Xapi.Client.Outbox	Durable outbox: retries, error classification, dead letters, idempotent resend	netstandard2.0, net10.0
Xapi.Lrs	AddXapiLrs / MapXapiLrs: an LRS inside your ASP.NET Core app	net10.0
Xapi.Lrs.Sqlite	SQLite storage and migrations for Xapi.Lrs	net10.0
Xapi.Lrs.PostgreSql	PostgreSQL storage and migrations for Xapi.Lrs	net10.0

The netstandard2.0 builds are for .NET Framework 4.6.2 and later and for Unity. JSON is read and written by hand with Utf8JsonReader and Utf8JsonWriter, without reflection, so the net10.0 builds of the Core, Client and Outbox packages can be trimmed and published with Native AOT; CI publishes samples/ConsoleClient that way and fails on any warning. Under Unity they pass their tests in the editor, in IL2CPP players on macOS, Linux, Android and the iOS Simulator, and in WebGL, where requests go through UnityWebRequestHandler from the Unity package in src/Xapi.Unity (docs/unity.md).

Quick start: send a statement

dotnet add package Xapi.Client

With using Xapi; and using Xapi.Client;:

using var http = new HttpClient();
var client = new XapiClient(http, new XapiClientOptions
{
    Endpoint = new Uri("https://lrs.example.com/xapi/"),
    Credentials = XapiCredentials.Basic(key, secret),
});

var statement = new Statement(
    Agent.FromMbox("[email protected]", "Ada Learner"),
    Verbs.Completed,
    new Activity(new Iri("https://example.com/courses/fire-safety")));

var id = await client.SaveStatementAsync(statement);
Console.WriteLine($"The LRS stored statement {id}");

The client asks the LRS which xAPI version to use, validates the statement for that version and sends it. To keep statements through network outages and restarts, put a StatementOutbox in front of the client; in an ASP.NET Core app, register both with AddXapiClient(...).AddOutbox(...) (example).

Quick start: host an LRS

In an ASP.NET Core app with the Xapi.Lrs.Sqlite package:

var builder = WebApplication.CreateBuilder(args);

builder.Services
    .AddXapiLrs(builder.Configuration.GetSection("Lrs"), options => options.MigrateOnStartup = true)
    .UseSqlite("Data Source=lrs.db");

var app = builder.Build();
app.MapXapiLrs("/xapi");
app.Run();

appsettings.json lists the credentials under Lrs, without their secrets:

{
  "Lrs": {
    "Credentials": [ { "Key": "my-app", "Scopes": [ "all" ] } ]
  }
}

The secret comes from user secrets or the environment (Lrs__Credentials__0__Secret). Clients then use https://<your app>/xapi/ as their endpoint, with the key my-app and that secret. The LRS guide covers scopes, delegated authentication, PostgreSQL, migrations and limits.

Conformance

The LRS passes all tests of the ADL LRS Conformance Test Suite at commit 5bc232d: 1,365 of 1,365 for xAPI 1.0.3 and 1,435 of 1,435 for 2.0.0, on SQLite and on PostgreSQL (as of commit 69bb8ff, 17 October 2026). Both batteries run against both databases in CI on every pull request, and the gate fails on any failing or skipped test.

In two places the suite expects more than IEEE 9274.1.1 requires, and the LRS follows the suite. docs/conformance.md explains both, and how the gate works.

Why another xAPI library

TinCan.NET, the library most .NET projects use today, has not changed since 2018: it targets net35, its calls block, it exposes Newtonsoft.Json types, and it has no xAPI 2.0 support. Teams that need durable sending end up writing their own outbox and retry logic. This project aims to be one maintained set of packages for both sides, tested against the conformance suite. The migration guide maps TinCan.NET calls and types to this library.

Documentation

• Getting started: install, send a statement, host an LRS
• Client: versions, credentials, dependency injection and retries, documents, attachments, errors
• Outbox: durable delivery, dead letters, storage
• LRS: options, storage providers, migrations, authentication, limits
• Signed statements
• xAPI versions: 1.0.3 and 2.0.0 differences and how the packages handle them
• Migrating from TinCan.NET
• Conformance
• Samples: a console client, an LRS embedded in an existing app, tests against an in-memory LRS, and a standalone LRS

The design decisions are recorded as architecture decision records.

The Documentation site has these guides and the API reference, built from main.

Status and versioning

Versions follow Semantic Versioning. During 0.x, minor versions can contain breaking changes; CHANGELOG.md lists them under "Breaking". Previews are published as -preview.N. The storage interfaces of Xapi.Lrs are marked experimental (XAPI0001): they are not covered by Semantic Versioning, also after 1.0, and may change in any release until they are declared stable (see Experimental storage API). Version 1.0.0 requires both conformance batteries to pass on both databases. What is planned for each version is tracked in the milestones.

Contributing, security, license

Contributions are welcome. Please open an issue before starting on anything larger than a small fix; see CONTRIBUTING.md. Report security problems privately as described in SECURITY.md.

Licensed under the Apache License 2.0. Third-party material is listed in THIRD-PARTY-NOTICES.md.

xAPI (Experience API) is a specification created by the Advanced Distributed Learning (ADL) Initiative and published as IEEE 9274.1.1-2023. "Tin Can API" is a former name of the specification. This project is an independent implementation and is not affiliated with, endorsed by, or certified by ADL, the U.S. Department of Defense, IEEE, or Rustici Software. IEEE is a registered trademark of The Institute of Electrical and Electronics Engineers, Inc.