🐍💻 Fix Npgsql “Bad Protocol Version” on macOS & .NET 6

If you’re building .NET 6 apps on macOS and connecting to PostgreSQL using Npgsql, you might encounter:

🚫 Bad Protocol Version errors

This usually means a mismatch between client and server expectations, but it can be resolved.

Perfect for developers wrestling with cross-platform database connections.

👉 Resolve the error here:
https://sslinsights.com/fix-npgsql-bad-protocol-version-macos-net6/

#dotnet6 #Npgsql #macOSDev #PostgreSQL #DevOps #Programming #ErrorFix #SSLInsights

Now gotten my Saturday article published. (As my search is picking up since I fixed it it's worth doing). So you can find a lot of articles I haven't publicised on X / LinkedIn on the site. This one is on a LONG term obsession about hierarchies in SQL server.
This article presents 5 ways to do it in EF with PostgreSQL.
Data Hierarchies: Managing Hierarchical Data with EF Core and PostgreSQL (Part 1)
https://www.mostlylucid.net/blog/efcore-hierarchical-data

#efcore #npgsql #csharp #ef

Hi #dotNET folks,
yesterday, Roji released #Npgsql 10.0 the .NET data provider for #PostgreSQL that targets .NET 10.0 and #NpgsqlEFCorePG the corresponding #EFCore provider.
Please check out the release notes at https://www.npgsql.org/doc/release-notes/10.0.html and https://www.npgsql.org/efcore/release-notes/10.0.html for new features and breaking changes.

Heute erstmal #VisualStudio 2026 und die neue #Rider und #Resharper Version installiert. Dabei einen Crash beim ersten Start von Rider gehabt und ihn an #Jetbrains gemeldet. Danach dann unser Projekt auf .NET 10 umgestellt und dabei gemerkt, dass noch das #Npgsql #NuGet Package fehlt, um komplett umzustellen. Also noch etwas warten... ansonsten hat alles funktioniert 😄!

Resolving Npgsql FileNotFoundException in .NET: A Guide to Database Connectivity
Resolve Npgsql FileNotFoundException errors in your database connectivity. Learn common causes & practical solutions for smooth PostgreSQL interactions. #DatabaseConnectivity #Troubleshooting #Npgsql #FileNotFoundException #PostgreSQL #JDBC
https://tech-champion.com/database/db2luw/resolving-npgsql-filenotfoundexception-in-net-a-guide-to-database-connectivity/

TIL you can't use both dataSourceBuilder.MapComposite<T> and NpgsqlConnection.GlobalTypeMapper.MapComposite<T> at the same time in #npgsql
docs: https://www.npgsql.org/doc/types/enums_and_composites.html?tabs=datasource

When you add mapping for composite type in GlobalTypeMapper - it replace datasource `UserTypeMapper` with global. Code here: https://github.com/npgsql/npgsql/blob/ab8e8db61617283603ac0350c1902222d710b92a/src/Npgsql/NpgsqlSlimDataSourceBuilder.cs#L423

Hi #dotNET folks,
today, we released multiple patch versions of #Npgsql, the .NET data provider for #PostgreSQL that fix https://www.cve.org/CVERecord?id=CVE-2024-32655
Nino, Nikita and Roji went out of their way and backported the fix to all versions back to 4.x to make sure that any version that might still be in reasonable use today gets patched.
Please make sure to upgrade to the latest patch version of Npgsql as soon as possible.
Versions containing the fix are:
≥ 8.0.3
≥ 7.0.7
≥ 6.0.11
≥ 5.0.18
≥ 4.1.13
≥ 4.0.14

Experiment: Outbox for .NET as a separate thing! 🤩

👉 https://github.com/rebus-org/Freakout

At the moment it supports Microsoft SQL Server and PostgreSQL.

Could it maybe be useful?

#sqlserver #mssql #postgres #postgresql #npgsql

Hi #dotNET developers,
in case you have already upgraded to #Npgsql 8.0 and are affected by a bug, you may be happy that Npgsql 8.0.1 has been released.
See https://github.com/npgsql/npgsql/milestone/110?closed=1 for the issues that have been closed in this release.
#NpgsqlEFCorePG the corresponding #EFCore provider has not been released yet but the existing release should be compatible with Npgsql 8.0.1

@DO9XE ja, das hatten wir bei #Npgsql auch: https://github.com/npgsql/npgsql/issues/5308

Man fragt sich viele Jahre warum man sich die ganze Zeit die Mühe macht, die Endianness zu berücksichtigen, wo doch ohnehin alles little endian ist und man big endian mit den eigenen Mitteln überhaupt nicht testen kann und dann kommt plötzlich einer aus einem Loch gekrochen, der mit BE-Architektur arbeitet und meldet einen Bug.
Das wertet die ganze Arbeit im Nachhinein auf.

Hi #dotNET folks,
today, Roji released #Npgsql 8.0 the .NET data provider for #PostgreSQL that targets .NET 8.0 and #NpgsqlEFCorePG the corresponding #EFCore provider.
Please check out the release notes at https://www.npgsql.org/doc/release-notes/8.0.html and https://www.npgsql.org/efcore/release-notes/8.0.html for new features and breaking changes.
While the big new thing is a rewrite of the internal type handling system to reduce binary size in AOT, there are quite a few other improvments and fixes to long-standing issues coming along with this.

Now that #PostgreSQL 16 has been released, Roji has also released the #Npgsql hotfixes 5.0.17, 6.0.10 and 7.0.6. They contain quite a few bugfixes and one replication-related compatibility fix for #PostgreSQL16, so make sure, you upgrade your #dotNET projects to the latest compatible version.

@khalidabuhakmeh
you definitely should try #Npgsql 8 once we've released it.
Nino is currently pushing binary size to it's limits while rewriting our internal type handlers: https://nitter.net/NinoFloris/status/1695226876585746545#m

@maartenballiauw @haney

Today Roji released #Npgsql 8.0.0-preview.1.
At the moment there are not many visible features added but Nikita, Nino and also Shay have have been hacking away with native AOT and reducing Npgsql's binary size, so if you're using AOT and care about binary size, it's probably worth to have some initial look at it and give feedback.
#dotNET
#PostgreSQL

Use Postgresql as a Pub/Sub server in a .NET app

https://github.com/glacasa/PostgresPubSub

I thought I would need to do some hacky stuff to make this work, but it just works out of the box thanks to Npgsql

#dotnet #npgsql #Postgresql

(edit : you can open the repo now)

Today Roji released #Npgsql 7.0.1 and 6.0.8.
Both are minor bugfix releases that shouldn't introduce any breaking changes and only fix a few bugs.
There's nothing in there, that I'd consider a big deal but if you're using Npgsql to connect your #dotNET application to #PostgreSQL and are hit by one of the bugs we've fixed, you might disagree and may want to upgrade your NuGet references.
See here for the fixed issues:
• https://github.com/Npgsql/Npgsql/issues?q=is%3Aissue+milestone%3A7.0.1
• https://github.com/Npgsql/Npgsql/issues?q=is%3Aissue+milestone%3A6.0.8

@davidfowl It's still the middle of the night over here but I'll probably start with backporting https://github.com/npgsql/npgsql/pull/4765 and afterwards I'll start working on https://github.com/npgsql/npgsql/issues/4462 which requires quite a bit of internal refactoring and cleanup of #Npgsql

Hey @oskardudycz,
thanks for doing the hard work of digging into parts of Npgsql that we haven't documented yet. I've responded in your PR.
You'll have to replace the call to Npgsql.Replication.Internal.LogicalReplicationConnectionExtensions.CreateLogicalReplicationSlot() at https://github.com/oskardudycz/PostgresOutboxPatternWithCDC.NET/blob/master/PostgresOutbox/Subscriptions/EventsSubscription.cs#L42 with a call to Npgsql.Replication.PgOutputConnectionExtensions.CreatePgOutputReplicationSlot() and then everything should work without patching #Npgsql.

Hi #dotNET folks,
yesterday, Roji released #Npgsql 7.0 the .NET data provider for #PostgreSQL that targets .NET 7.0 and #NpgsqlEFCorePG the corresponding #EFCore provider.
Please check out the release notes at https://www.npgsql.org/doc/release-notes/7.0.html and https://www.npgsql.org/efcore/release-notes/7.0.html for new features and breaking changes.
There's a lot of cool new stuff to try out!

@danielwhite 👋
Maybe a bit less than others since I've been working with the prerelreases for months already because I'm working on stuff that is supposed to be released alongside with it.
#Npgsql