Datalust, the company behind Seq

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

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News and announcements

Seq 2023.4 Maintenance Release

Thursday, 28 September 2023

We've just released Seq 2023.4.10219 with some improvements to the new range selector, along with a handful of bug fixes.

Seq User Preferences screen with new Range selector options input, showing "5m, 15m, 1h, 1d, 7d, 30d, 90d, 365d"
The new "Range selector options" setting; this is perfect if you find that you frequently need ranges such as "2d" that are

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

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.