Perf Hints

Improve C++ (C++11+) performance using Abseil “Performance Hints” (Jeff Dean & Sanjay Ghemawat): estimation + profiling, API/bulk design, algorithmic wins, cache-friendly memory layout, fewer allocations, fast paths, caching, and compiler-friendly hot loops. Use for performance code reviews, refactors, and profiling-driven optimizations. Keywords: performance, latency, throughput, cache, allocation, memory layout, InlinedVector, string_view, Span, flat_hash_map, pprof, perf.

9 stars 2 forksSoftware Development

Install

skills CLI (Claude Code, Cursor, Codex and more)

npx skills add omarkilani/perf-hints --skill perf-hints

Manual install

git clone --depth 1 https://github.com/omarkilani/perf-hints.git /tmp/perf-hints
mkdir -p ~/.claude/skills
cp -r /tmp/perf-hints/. ~/.claude/skills/perf-hints

Personal skills live in ~/.claude/skills. Use .claude/skills in a project folder to share a skill with your team.

From the SKILL.md

# C++ Performance Hints (Jeff Dean & Sanjay Ghemawat style)

This skill packages key ideas from Abseil’s **Performance Hints** document.

Use it to:

- review C++ code for performance risks
- propose high-impact optimizations with **explicit tradeoffs**
- design APIs/data structures that keep future optimizations possible
- write an experiment plan (profile + microbenchmark) to validate changes

## Scope and guardrails

- **Scope:** single-process / single-binary performance (CPU, memory, allocations, cache behavior).
- **Do not:** change externally observable behavior unless the user explicitly agrees.
- **Do not:** introduce undefined behavior, data races, or brittle “clever” micro-opts without evidence.
- **Default philosophy:** choose the faster alternative **when it doesn’t materially harm readability or complexity**; otherwise, measure first.

## When to apply

Use this skill when the task involves any of:

- reducing **latency** or improving **throughput**
- cutting **memory footprint** or **allocation rate**
- improving **cache locality** / reducing cache misses
- designing performant **APIs** (bulk ops, view types, threading model)
- reviewing performance-sensitive C++ changes
- interpreting a **flat profile** and finding next steps

## What to ask for (minimum inputs)

If you don’t have enough information, ask for the smallest set that changes your recommendation quality:

1. **Goal:** latency vs throughput vs memory (and the SLO if any)

Read the full skill on GitHub

Details

Skill name: perf-hints
Repository: omarkilani/perf-hints
Repo updated: 21 December 2025

FAQ

What does the Perf Hints skill do?

How do I install the Perf Hints skill?

skills CLI (Claude Code, Cursor, Codex and more): npx skills add omarkilani/perf-hints --skill perf-hints. Skills go in ~/.claude/skills (personal) or .claude/skills (project), and Claude loads them automatically when a task matches the description.

Is Perf Hints popular?

It lives in omarkilani/perf-hints, which has 9 GitHub stars and 2 forks.

Related skills

User Stories

felipereisdev/user-stories-skill

Analyzes a codebase and breaks down a goal into implementable user stories with clear acceptance criteria. Use when planning a new feature, estimating work, or creating a development roadmap. Explores the code before asking anything; when the goal is ambiguous, asks at most 5 blocking multiple-choice questions with a recommended answer, and records assumptions and open questions in the plan. Outputs execution-ready stories (schema v2: type, status, a verify check per criterion, dependencies with reasons, interfaces, files to reuse, file conflicts for parallel work) to .context/[goal-slug]-plan

Software Development

Cc Claude Codex

leyuan0602-glitch/cc-claude-codex

Development skill where Claude Code acts as supervisor and Codex acts as executor. Auto-trigger for implementation, debugging, refactoring, testing, and other dev tasks.

Software Development

Cl1 Base

SeanCole02/cl1-base

Build or adapt baseline CL1 human-neuron models, stimulation loops, and evaluation workflows. Use when Codex needs to design or modify CL1 training code, UDP stimulation and spike protocols, safe stimulation ranges, Same Frame Encoding (SFE), ablations, feedback-channel logic, or hardware-aware data and training loops for CL1 systems.

Software Development

Bilibili Digest

lll888666/bilibili-digest

解析 B 站视频并生成干货报告：提取字幕或本地 faster-whisper 转录、抓取高赞评论、总结要点、提取资源链接、输出 Mermaid 思维导图。零第三方 API Key。当用户提供 bilibili.com 链接、BV 号，或说「总结这个 B 站视频」「B 站干货」「视频逐字稿」「消化 B 站视频」时必须使用本 skill。

Software Development

4d V21

Ganbin/4d-development-skill

Comprehensive 4D v21 development expert with embedded official documentation. Covers ORDA patterns, entity classes, data model classes, queries, classic methods, data types, error handling, forms, events, web server, and REST API. Use when working with 4D files (.4dm), 4D language questions, 4D project structure, entity classes, ORDA queries, database operations, form development, web server configuration, REST API usage, or any 4D-specific syntax issue. Includes full official 4D v21 documentation for on-demand retrieval. Triggers on: .4dm files, 4D code, ORDA, entity selection, dataclass, 4D

Software Development

Typescript Engineering

bluenzzz/typescript-engineering

Use when implementing, reviewing, debugging, or refactoring TypeScript applications or libraries, including type modeling, external input validation, TSConfig, ESM/CommonJS issues, and measured performance work.

Software Development

Browse the most popular Claude skills, all software development skills, or write your own with the skills generator.