Datalust, the company behind Seq

Seq is the intelligent search, analysis, and alerting server built specifically for modern structured log data.

Seq Screenshot

News and announcements

Seq 2023.4

Wednesday, 06 September 2023

TL;DR: Download Seq 2023.4 at or pull datalust/seq from Docker Hub.

Seq 2023.4 lands some long-awaited user experience improvements: upgraded autocomplete, a new range selector, and dashboards get custom time ranges at last!

Upgraded autocomplete

Seq has a rich query language with a

Easy in-proc debugging for Seq Apps

Tuesday, 29 August 2023

TL;DR: the new Seq.Apps.Testing package makes it easy to interactively debug Seq Apps in C#, by hosting them in a console app and sending events directly from Serilog.

Seq Apps are server-side plug-ins that send and receive events and notifications. A huge number have been published to

Exploding Collections 💥

Tuesday, 18 July 2023

TL;DR: Seq 2023.3 introduces the unnest set function and lateral cross joins, enabling natural queries over nested collections in log events.

Seq 2023.3 showing query with lateral unnest clause.

Here's the essence of the problem: you log some basic information about order placement in your online coffee roasting service; the natural way to express

New from Datalust

On .NET Live - Application logs and diagnostics with Serilog

Nicholas Blumhardt talks application diagnostics with Cecil Phillip in On .NET Live.

.NET Rocks! #1647 - Rust and C# with Ashley Mannix

Ashley Mannix talks with Carl and Richard about the combination of Rust and C# used at Datalust.

C# and Rust: Combining Managed and Unmanaged Code Without Sacrificing Safety, NDC Oslo 2019

Ashley Mannix explores the tools that .NET and Rust give us to design and build safe and robust hybrid applications.

Parsing in C# from First Principles, NDC Sydney 2018

Nicholas Blumhardt talks about Superpower, the library we built for parsing SQL queries in Seq, and the foundational principles behind it.

Open Source and the Future of Seq

Brendan Richards interviews Nicholas Blumhardt about Open Source, Rust, Seq, Serilog, and more, in this AMA from NDC Sydney 2018.

Using Structured Logging for Production Insight

Microsoft's Damian Brady and Nicholas Blumhardt talk structured logging in this episode of The DevOps Lab.

.NET Rocks! #1466 - The Evolution of Serilog

Richard Campbell, Carl Franklin, and Nicholas Blumhardt talk all things logging, diagnostics, and monitoring in this .NET Rocks! episode recorded at NDC Oslo 2017.

Serilog: Instrumentation that Works for You, NDC Oslo 2017

Nicholas Blumhardt presents a complete walk-through of Serilog and modern structured logging at NDC Oslo 2017.