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Type Design Performance

Checked
aaronontheweb·vlatest·other·MIT

Helps with design, performance optimization as part of agent workflows workflows.

Repository

Install on your platform

Showing Claude Code. One command installs this skill into any of the agents below.

  1. 1

    Run this in your project

    terminal
    $ npx skills add aaronontheweb/dotnet-skills --skill type-design-performance -a claude-code

  2. Uses the open-source skills CLI and needs Node.js. Add -g to install it for your user instead of this project.

What we know about this skill

Publisher

aaronontheweb

Taken from the source listing. We haven't verified who controls this account.

Install target

Live repository

Not pinned. Installing fetches whatever the repository holds at the time you run the command.

No human has reviewed this code. The checks below are a static scan of the files at one commit — nobody has run this skill or judged whether it works. A skill runs with whatever access you give your agent, so read the source before you install it.

Automated safety checks

scanned

This skill passed all 6 checks. We read its files at one commit and looked for the things that make a skill dangerous to run — not for whether it works.

  • Declares what it does: passed

    SKILL.md parses and declares a name and a description.

    SKILL.md exists, its frontmatter parses, and it declares a name and a description.

  • No undeclared network calls: passed

    Makes no network calls.

    Every host the skill dials — from its scripts, its config endpoints or the commands it tells the agent to run — is either well-known package and API infrastructure or declared in its own frontmatter. Links in documentation are not counted.

  • No obfuscated payloads: passed

    No encoded or obfuscated payloads.

    No base64, hex or compressed blob is decoded and then executed, and no encoded shell commands.

  • No credential access: passed

    Reads no keys, tokens, keychains or credential files.

    Neither the code nor the SKILL.md instructions read SSH keys, cloud credentials, keychains, token stores, browser cookie databases or dotfiles that hold secrets.

  • No pipe-to-shell installers: passed

    No pipe-to-shell or download-and-run installers.

    No `curl … | sh` pattern, in the code or in the instructions, that runs code fetched at run time.

  • Pinned to a commit: passed

    Scanned aaronontheweb/dotnet-skills at e426ed93a9.

    The exact upstream commit SHA that was scanned is recorded, so the result refers to specific bytes.

Commit
e426ed93a9
Manifest
skills/csharp-type-design-performance/SKILL.md
Scanned
1 file, 375 lines
This is a static scan, not a review. It reads the skill's files; it does not run them, and it cannot tell you whether the skill is any good or whether the code does what its description says. A skill runs with whatever access you give your agent.
What each check looks for →

About this skill

What it does

This skill provides guidance and best practices for designing types and APIs in .NET with a focus on performance optimization. It emphasizes principles like sealing classes, using readonly structs for value types, preferring static pure functions, deferring enumeration, and returning immutable collections. The goal is to help developers write more efficient and maintainable code by applying these design patterns.

When to use it

  • When designing new types and APIs in .NET.
  • During code reviews to identify potential performance bottlenecks related to type design.
  • To determine whether a class, struct, or record is the most appropriate choice for a given scenario.
  • While working with collections and enumerables to ensure efficient data handling.

Key capabilities

  • Provides guidance on sealing classes to enable JIT devirtualization and communicate API intent.
  • Recommends using readonly structs for small, immutable value types to prevent defensive copies.
  • Encourages the use of static pure functions for improved performance and testability.
  • Suggests deferring enumeration until it's actually needed.
  • Promotes returning immutable collections from API boundaries.

Example prompts

  • "I'm designing a new data type in C#. What are some considerations for performance?"
  • "Should I use a class or struct for this value object? What are the tradeoffs?"
  • "How can I optimize the way I’m working with collections in my .NET application?"

Tips & gotchas

  • This skill focuses specifically on type design and performance optimization within .NET. It is not a general coding assistant.
  • Sealing classes communicates intent; be sure you understand the implications before doing so, as it prevents inheritance.