Laszlo

Hello, I am Laszlo

Software-Engineer, .NET developer

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Try-Catch-Finally in C#

09/20/2026

Introduction

C#'s try-catch-finally statements are fundamental building blocks of the language. While most developers learn exception handling early in their careers and use it frequently in production applications, the mechanics can be surprisingly complex. Exception handling is often discussed during developer job interviews, and even experienced developers can struggle with some of its nuances.

A Complex Case

Let's examine a challenging code snippet that demonstrates these complexities. What does the following code print to the console?

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Cryptographic Signatures with a TPM

09/11/2026

In my previous post, I compared different signature algorithms listed primarily in RFC 9421, extended with MLDsa44. The focus of that comparison was performance rather than cryptographic strength. I ran the tests on multiple hardware configurations and operating systems, but performed the signing in software.

In this post, I use Windows and a TPM to sign data. The TPM protects the private key and performs the private key operation, while public key operations may be handled by the provider or operating system The test setup matches the previous tests as closely as possible.

Message sizes:

  • A small message, roughly the size of a single JSON property value.
  • A medium message, where the plaintext is roughly the size of a few properties (93 bytes).
  • A 1 KB message.

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Crypto Signatures

09/08/2026

In this post, I look at the different signature algorithms available to .NET developers. I am going to compare these algorithms from a performance point of view. However, I am not going to focus on their security strength.

Signature algorithms are used to provide integrity and authenticity for data. At the network level, a TLS connection provides encryption, but this is often not enough because some environments may terminate TLS connections. For example, load balancers and ingress proxies often terminate the TLS connection (and sometimes even downgrade the HTTP protocol version) before forwarding requests to the actual server instance. By signing each request or response message individually, a receiver can validate the signature of the sender. It can confirm that a message has not been tampered with and that it originates from the sender rather than from a man-in-the-middle attacker.

What it does not do:

  • It does not protect against replay attacks by itself, unless a nonce, idempotency key, or timestamp is included in the signed data.
  • Signatures do not encrypt the message. Anyone with access to the message can still read it. This means TLS is still required at the connection level.

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SIMD Gather and Scatter Anagram

08/25/2026

Introduction

One of the most difficult problems with SIMD is handling non-contiguous memory access. To address this challenge AVX-512 adds gather and scatter instructions to load and store memory in an array at non-adjacent indexes. These instructions enable a whole new set of algorithms to be vectorized using SIMD operations.

Gather is a single instruction that loads data from non-adjacent indexes of an array into a Vector register. Scatter is a single instruction that stores data at non-adjacent indexes to an array from a Vector register.

Both instructions have a source/destination register parameter, a reference to an array parameter, and another vector parameter containing the indexes for each lane to be loaded or stored.

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Using Prioritized Channel

08/01/2026

In .NET 9, a new UnboundedPrioritized channel type has been introduced to System.Threading.Channels. This feature has been available since version 8 of the Channel's NuGet package and is compatible with older .NET versions.

Channels provide thread-safe data structures for producer/consumer scenarios. In this pattern, one or more producers add items to a channel while one or more consumers read from it independently.

Two types of channels exist:

  • Bounded channels: Have a maximum size limit with customizable behavior when full
  • Unbounded channels: Have no size limit (beyond system memory constraints)

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