The PhoenixML Platform

XML/JSON processing engines, an embedded document database, and integration pipelines — built from the ground up for .NET.

Processing Engine

PhoenixML includes a standards-complete XML/JSON processing engine supporting the latest W3C specifications. No Java dependency. No COM interop. Pure .NET, async throughout.

✓ XSLT 4.0 with streaming and higher-order functions
✓ XQuery 4.0 with FLWOR, window clauses, update facility
✓ XPath 4.0 with arrow operators and inline functions
✓ Full JSON support via maps and arrays
✓ Extension functions in C#

Document Database

An embedded document store optimized for XML and JSON documents with ACID transactions, MVCC concurrency, and rich indexing for fast queries.

✓ LMDB-backed storage (memory-mapped, crash-safe)
✓ ACID transactions with MVCC
✓ Path, value, and full-text indexes
✓ XQuery-native document querying
✓ Container-based organization
✓ Embeddable or server-mode deployment

Architecture

  +-------------------------------------------------------+
  |                    Your .NET App                       |
  +-------------------------------------------------------+
            |                           |
  +---------v---------+     +-----------v-----------+
  |  XSLT / XQuery /  |     |    Document Database   |
  |  XPath Engine      |     |    (LMDB Storage)      |
  +-------------------+     +-----------------------+
            |                           |
  +---------v---------------------------v-----------+
  |              PhoenixmlDb Core                    |
  |    XDM Model  |  Indexing  |  Serialization      |
  +--------------------------------------------------+
            |
  +---------v---------+
  |   NuGet Package    |
  |   Apache 2.0       |
  +-------------------+

Get started in seconds

# Install the XSLT engine
dotnet add package PhoenixmlDb.Xslt

# Install the XQuery engine
dotnet add package PhoenixmlDb.XQuery

What you get at each tier

Feature	Community	Pro	Enterprise
XSLT 4.0 / XQuery 4.0 / XPath 4.0	✓	✓	✓
Document Database	✓	✓	✓
CLI Tools	✓	✓	✓
Server Mode	—	✓	✓
Commercial Use	—	✓	✓
Priority Support	—	✓	✓
Redistribution License	—	—	✓
Dedicated Support / SLA	—	—	✓
Custom Integrations	—	—	✓