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hss.db

discontinued

by HighSpeed-Solutions LLC · since 2009

Commercial embedded object database for .NET and Xamarin with a LINQ query engine (c. 2009–2017).

objectrelationalembedded libraryproprietarylegacy
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discontinued. No packages since 4.0.0 (March 2016) and the vendor site has been offline since about 2017. Consider LiteDB or SQLite.

Overview

hss.db was an embedded object-relational database for .NET from HighSpeed-Solutions LLC. Written entirely in C#, mostly as a portable class library with thin per-platform adapters, it stored .NET objects with optional predefined schemas, binary serialization and encryption, and queried them through an IQueryable LINQ provider, with ACID transactions and zero configuration. Version 4.0, published on NuGet in March 2016, targeted .NET 4.6, Xamarin Android and iOS, Windows Phone 8.1 and Windows 10 UWP, and a LINQPad driver was available. It was sold commercially. The vendor's site went dark around 2017 and no newer packages exist; LiteDB, Realm or SQLite with an ORM cover the same ground today.

Embedded / in-processMobile & offline

Strengths & trade-offs

Strengths

  • +Full IQueryable LINQ provider over embedded objects
  • +Single C# codebase across desktop, UWP and Xamarin mobile
  • +Encryption and ACID transactions with zero configuration

Trade-offs

  • −Vendor gone; no updates or support
  • −Closed source and tied to 2016-era .NET targets

Great for

  • +Maintaining legacy Xamarin or UWP apps built on it
  • +Planning a migration of such apps to LiteDB or SQLite

Think twice for

  • −New .NET or MAUI projects

Capabilities

Native or official first-party support · 4 of 25 tracked

✓Transactions
✓Secondary indexes
✓Durable persistence
✓Encryption at rest
–Joins
–Full-text search
–Vector search
–Geospatial
–JSON
–Change data capture
–Triggers
–Stored procedures
–Materialized views
–TTL / expiry
–Pub/Sub
–Columnar storage
–In-memory
–Compression
–Role-based access
–Time travel
–Branching
–Online schema changes
–Streaming ingest
–Offline sync
–Runs in WebAssembly

Scale & consistency

Comfortable data size
Small · ≤ 100 GB
Horizontal scaling
None
Multi-region
No
Transactions
Full ACID
Consistency
Strong
Schema
Flexible
Architecture
Embedded
Query languages
LINQ

Deployment

Self-hosted Vendor-managed cloud Serverless Embedded Edge Kubernetes operator

Ecosystem

apis & protocols.NET API, LINQPad driver
client languagesC#

Alternatives to hss.db

Compare all→
LiteDBDocument10.8

Serverless single-file NoSQL document database for .NET, in the spirit of SQLite.

hss-db vs litedb →
SQLiteRelational75.5

The in-process SQL engine that ships in every phone, browser and OS: one file, zero servers.

hss-db vs sqlite →
Realm (Atlas Device SDK)Object25.2

Object-oriented mobile database whose MongoDB sync service is gone; the local engine survives as open source.

hss-db vs realm →
ObjectBoxObject12.4

Fast on-device object database with built-in HNSW vector search and an optional commercial sync server.

hss-db vs objectbox →
PowerSyncRelational23.3

Sync engine that keeps on-device SQLite in sync with Postgres, MongoDB, MySQL or SQL Server.

hss-db vs powersync →
InterBaseRelational18.3

Embarcadero's small-footprint SQL database for servers and embedded apps, with built-in AES encryption.

hss-db vs interbase →

hss.db FAQ

What is hss.db?

hss.db is an object database by HighSpeed-Solutions LLC, first released in 2009. hss.db was an embedded object-relational database for .NET from HighSpeed-Solutions LLC. Written entirely in C#, mostly as a portable class library with thin per-platform adapters, it stored .NET objects with optional predefined schemas, binary serialization and encryption, and queried them through an IQueryable LINQ provider, with ACID transactions and zero configuration. Version 4.0, published on NuGet in March 2016, targeted .NET 4.6, Xamarin Android and iOS, Windows Phone 8.1 and Windows 10 UWP, and a LINQPad driver was available. It was sold commercially. The vendor's site went dark around 2017 and no newer packages exist; LiteDB, Realm or SQLite with an ORM cover the same ground today.

Is hss.db open source?

No. hss.db is proprietary, closed-source software.

Does hss.db support ACID transactions?

Yes. hss.db supports full ACID transactions, with strong consistency.

Does hss.db scale horizontally?

hss.db does not scale horizontally; it runs on a single node, so you scale it up rather than out. It is comfortable at small scale (≤ 100 GB).

How can I run hss.db?

You can embed it in your application.

What is hss.db best for?

hss.db is a strong fit for maintaining legacy Xamarin or UWP apps built on it and planning a migration of such apps to LiteDB or SQLite. Think twice for new .NET or MAUI projects.

What are the best alternatives to hss.db?

Common alternatives to hss.db include LiteDB, SQLite, Realm (Atlas Device SDK), ObjectBox and PowerSync. The right choice depends on your workload, scale and hosting; WhichDB's smart match ranks them against your requirements.

Is hss.db still maintained?

hss.db is discontinued. No packages since 4.0.0 (March 2016) and the vendor site has been offline since about 2017. Consider LiteDB or SQLite.

How popular is hss.db?

hss.db has little measurable public adoption today, so it ranks near the bottom of the WhichDB Score.