# Modern Cpp

Guides C++ code toward modern idioms (C++20/23/26).

- Repository: https://github.com/trailofbits/skills (7935 stars)
- Category: Security
- License: CC-BY-SA-4.0
- Last updated: 2026-10-28
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add trailofbits/skills --skill modern-cpp -g -a claude-code -y`
Codex: `npx skills add trailofbits/skills --skill modern-cpp -g -a codex -y`
Cursor: `npx skills add trailofbits/skills --skill modern-cpp -g -a cursor -y`
Gemini CLI: `npx skills add trailofbits/skills --skill modern-cpp -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add trailofbits/skills`

## Description

Guides C++ code toward modern idioms (C++20/23/26). Use when writing new C++ code, modernizing legacy patterns, or working on security-critical C++. Replaces raw pointers with smart pointers, SFINAE with concepts, printf with std::print, error codes with std::expected.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Modern C++

Guide for writing modern C++ using C++20, C++23, and C++26 idioms. Focuses on patterns that eliminate vulnerability classes and reduce boilerplate, with a security emphasis from Trail of Bits.

## When to Use This Skill

- Writing new C++ functions, classes, or libraries
- Modernizing existing C++ code (pre-C++20 patterns)
- Choosing between legacy and modern approaches
- Working on security-critical or safety-sensitive C++
- Reviewing C++ code for modern idiom adoption

## When NOT to Use This Skill

- **User explicitly requires older standard**: Respect constraints (embedded, legacy ABI)
- **Pure C code**: This skill is C++-specific
- **Build system questions**: CMake, Meson, Bazel configuration is out of scope
- **Non-C++ projects**: Mixed codebases where C++ isn't primary

## Anti-Patterns to Avoid

The rest: https://github.com/trailofbits/skills/blob/HEAD/plugins/modern-cpp/skills/modern-cpp/SKILL.md