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Cloudflare Workers Multi Lang

Multi-language Workers development with Rust, Python, and WebAssembly. Use when building Workers in languages other than JavaScript/TypeScript, or when integrating WASM modules for performance-critical code.

pythontypescriptjavascriptrustcloudflareperformance
By secondsky
17928Updated 1 day agoTypeScriptMIT

Skill Content

# Multi-Language Workers Development

Build Cloudflare Workers using Rust, Python, or WebAssembly for performance-critical operations.

## Language Comparison

| Feature | JavaScript/TS | Rust | Python |
|---------|---------------|------|--------|
| **Startup** | Fast | Fastest (WASM) | Moderate |
| **CPU Perf** | Good | Excellent | Good |
| **Memory** | Higher | Lower | Higher |
| **Bundle Size** | Smaller | Medium | Larger |
| **Type Safety** | Optional (TS) | Strict | Optional |
| **Best For** | General apps | CPU-intensive | Data/ML |

## Quick Decision

```
Need maximum performance? ā†’ Rust/WASM
Heavy computation (crypto, image processing)? ā†’ Rust/WASM
Data processing, ML inference? ā†’ Python
General web apps? ā†’ JavaScript/TypeScript
```

## Top 10 Multi-Lang Errors

| Error | Language | Cause | Solution |
|-------|----------|-------|----------|
| `WebAssembly.instantiate() failed` | Rust | Invalid WASM | Check wasm-pack build output |
| `Module parse failed: Unexpected token` | Rust | ESM/CJS mismatch | Use `--target bundler` |
| `Cannot find module` | Python | Missing dep | Add to pyproject.toml |
| `Out of memory` | All | Large WASM | Enable streaming instantiation |
| `Exceeded CPU time limit` | All | Long computation | Chunk processing |
| `wasm-bindgen version mismatch` | Rust | Dep conflict | Align versions in Cargo.toml |
| `RuntimeError: unreachable` | Rust | Panic in WASM | Add proper error handling |
| `TypeError: not a function` | Rust | Missing export | Add `#[wasm_bindgen]` attribute |
| `Python worker startup timeout` | Python | Slow init | Minimize imports |
| `SharedArrayBuffer not supported` | All | Security | Add COOP/COEP headers |

## Rust Quick Start

```bash
# Install tools
cargo install wasm-pack

# Create project
cargo new --lib my-worker
cd my-worker

# Add to Cargo.toml
cat >> Cargo.toml << 'EOF'
[lib]
crate-type = ["cdylib"]

[dependencies]
wasm-bindgen = "0.2"
worker = "0.3"
console_error_panic_hook = "0.1"

[profile.release]
opt-level = "s"
lto = true
EOF
```

```rust
// src/lib.rs
use worker::*;

#[event(fetch)]
async fn fetch(req: Request, env: Env, _ctx: Context) -> Result<Response> {
    console_error_panic_hook::set_once();

    Router::new()
        .get("/", |_, _| Response::ok("Hello from Rust!"))
        .get("/compute", |_, _| {
            // CPU-intensive computation
            let result = heavy_computation();
            Response::ok(format!("Result: {}", result))
        })
        .run(req, env)
        .await
}

fn heavy_computation() -> u64 {
    (1..1_000_000).filter(|n| is_prime(*n)).count() as u64
}

fn is_prime(n: u64) -> bool {
    if n < 2 { return false; }
    (2..=(n as f64).sqrt() as u64).all(|i| n % i != 0)
}
```

## Python Quick Start (Workers for Platforms)

```toml
# pyproject.toml
[project]
name = "my-worker"
version = "0.1.0"
requires-python = ">=3.12"
dependencies = []

[build-system]
requires = ["hatchling"]
build-backend = "hatchling.build"
```

```python
# src/entry.py
from js import Response, Headers

async def on_fetch(request, env):
    url = request.url

    if "/compute" in url:
        result = heavy_computation()
        return Response.new(f"Result: {result}")

    return Response.new("Hello from Python!")

def heavy_computation():
    """CPU-intensive computation"""
    return sum(1 for n in range(2, 100000) if is_prime(n))

def is_prime(n):
    if n < 2:
        return False
    return all(n % i != 0 for i in range(2, int(n**0.5) + 1))
```

## WASM Module Integration

```typescript
// Load and use WASM module in TypeScript Worker
import wasmModule from './pkg/my_lib_bg.wasm';
import { init, process_data } from './pkg/my_lib';

let wasmInstance: WebAssembly.Instance;

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    // Initialize WASM once
    if (!wasmInstance) {
      wasmInstance = await WebAssembly.instantiate(wasmModule);
      init();
    }

    // Use WASM function
    const result = process_data(inputData);

    return Response.json({ result });
  },
};
```

## When to Load References

| Reference | Load When |
|-----------|-----------|
| `references/rust-workers.md` | Building Workers with Rust/WASM |
| `references/python-workers.md` | Using Python on Workers for Platforms |
| `references/wasm-integration.md` | Integrating WASM modules in any Worker |

## Performance Tips

1. **WASM Initialization**: Cache instance, use streaming
2. **Memory**: Use typed arrays for data transfer
3. **Bundle Size**: Enable LTO, strip debug info
4. **Cold Starts**: Keep WASM modules small
5. **Data Transfer**: Minimize JS/WASM boundary crossings

## See Also

- `workers-performance` - General optimization techniques
- `workers-testing` - Testing multi-language Workers
- `cloudflare-worker-base` - Basic Workers setup

How to use

  1. Copy the skill content above
  2. Create a .claude/skills directory in your project
  3. Save as .claude/skills/claude-skills-cloudflare-workers-multi-lang.md
  4. Use /claude-skills-cloudflare-workers-multi-lang in Claude Code to invoke this skill

README

View on GitHub

Claude Code Skills Collection

170 production-ready skills for Claude Code CLI

Version 3.3.1 | Last Updated: 2026-05-14

<div align="center">

šŸ”Œ Platform Support

This repository uses Claude Plugin Patterns ā€” natively supported by:

PlatformStatusNotes
Claude Codeāœ… NativeFull marketplace support
Factory Droidāœ… NativeFull marketplace support
</div> **For all other Platforms like opencode, codex and others, you can use https://github.com/enulus/OpenPackage **

A curated collection of battle-tested skills for building modern web applications with Cloudflare, AI integrations, React, Tailwind, and more.

PS: if skills.sh warns about any skill: Their scan process is a outdated LLM which flags newest versions pins (like in ZOD) as non existent and by that potentially malicous.

Quick Start

Marketplace Installation (Recommended)

# Add the marketplace
/plugin marketplace add https://github.com/secondsky/claude-skills

# Install individual skills as needed
/plugin install cloudflare-d1@claude-skills
/plugin install tailwind-v4-shadcn@claude-skills
/plugin install ai-sdk-core@claude-skills

See MARKETPLACE.md for complete catalog of all 170 skills.

Bulk Installation (Contributors)

# Clone the repository
git clone https://github.com/secondsky/claude-skills.git
cd claude-skills

# Install all 170 skills at once
./scripts/install-all.sh

# Or install individual skills
./scripts/install-skill.sh cloudflare-d1

Repository Structure

This repository contains 170 production-tested skills for Claude Code, each focused on a specific technology or capability.

Individual Skills: Each skill is a standalone unit with:

  • SKILL.md - Core knowledge and guidance
  • Templates - Working code examples
  • References - Extended documentation
  • Scripts - Helper utilities

Installation Options:

  1. Individual - Install only the skills you need via marketplace
  2. Bulk - Install all 170 skills using ./scripts/install-all.sh

Available Skills (170 Individual Skills)

Each skill is individually installable. Install only the skills you need.

Full Catalog: See MARKETPLACE.md for detailed listings.

Categories

CategorySkillsExamples
tooling29turborepo, plan-interview, code-review
frontend26nuxt-v4, nuxt-v5, tailwind-v4-shadcn, tanstack-query, nuxt-studio, maz-ui, threejs
cloudflare21cloudflare-d1, cloudflare-workers-ai, cloudflare-agents
ai20openai-agents, claude-api, ai-sdk-core
api16api-design-principles, graphql-implementation
web10hono-routing, firecrawl-scraper, web-performance
mobile7swift-best-practices, react-native-app, react-native-skills
database6drizzle-orm-d1, neon-vercel-postgres, supabase-postgres-best-practices
security6csrf-protection, access-control-rbac
auth4better-auth
testing4vitest-testing, playwright-testing
design4design-review, design-system-creation
woocommerce4woocommerce-backend-dev
cms4hugo, sveltia-cms, wordpress-plugin-core
architecture3microservices-patterns, architecture-patterns
data3sql-query-optimization, recommendation-engine
seo2seo-optimizer, seo-keyword-cluster-builder
documentation1technical-specification

How It Works

Auto-Discovery

Claude Code automatically checks ~/.claude/skills/ for relevant skills before planning tasks:

User: "Set up a Cloudflare Worker with D1 database"
           ā†“
Claude: [Checks skills automatically]
           ā†“
Claude: "Found cloudflare-d1 skills.
         These prevent 12 documented errors. Use them?"
           ā†“
User: "Yes"
           ā†“
Result: Production-ready setup, zero errors, ~65% token savings

Note: Due to token limits, not all skills may be visible at once. See āš ļø Important: Token Limits below.

Skill Structure

Each skill includes:

skills/[skill-name]/
ā”œā”€ā”€ SKILL.md              # Complete documentation
ā”œā”€ā”€ .claude-plugin/
ā”‚   ā””ā”€ā”€ plugin.json       # Plugin metadata
ā”œā”€ā”€ templates/            # Ready-to-copy templates
ā”œā”€ā”€ scripts/              # Automation scripts
ā””ā”€ā”€ references/           # Extended documentation

Recent Additions

May 2026

Supply Chain Security (cross-cutting):

  • dependency-upgrade expanded with Socket CLI integration ā€” proactive malicious package detection, typosquatting alerts, and CI/CD security gates. New 418-line reference guide, 2 GitHub Actions templates, and expanded supply chain security comparison (3 tools)
  • 31 skills now include "Secure Installation" guidance ā€” contextually-tailored security sections across all high-risk skill categories (scaffolding, MCP/agent SDKs, multi-provider installs, Docker, CI/CD). Covers 8 Bun skills, 5 Nuxt skills, 6 Cloudflare skills, 4 AI/agent skills, and 8 frontend/tooling skills
  • Supply chain security is now a first-class cross-cutting concern woven into the skill collection ā€” not a standalone topic

February - April 2026

Full-Stack Frameworks:

  • nuxt-v5 (v1.0.0) - Full Nuxt 5 support with 4 skills (core, data, server, production), 3 diagnostic agents, and interactive setup wizard
  • supabase-postgres-best-practices - 30 Postgres optimization rules from Supabase across 8 categories
  • threejs (v1.0.0) - 3D web graphics: scenes, geometries, shaders, animations, post-processing

Infrastructure:

  • JSON schema validation - Automated plugin.json validation with CI support
  • GitHub issue templates - Skill-specific issue templates for bug reports, feature requests, and submissions

Plugin Enhancements:

  • mutation-testing - Added Bun native runner support
  • dependency-upgrade - Added supply chain security content

December 2025 - January 2026

Frontend Expansion:

  • nuxt-studio (v1.0.0) - Visual CMS for Nuxt Content with live preview, OAuth auth, and R2 storage integration
  • maz-ui (v1.0.0) - 50+ Vue/Nuxt components with theming, i18n, form generation, and 14 composables

Developer Workflow:

  • plan-interview (v2.0.0) - Adaptive interview-driven spec generation with autonomous quality review
  • turborepo (v2.8.0) - Updated to official Vercel skill with enhanced monorepo build optimization

Mobile Development:

  • react-native-skills (v1.0.0) - React Native & Expo best practices with performance optimization patterns

Enhanced Authentication:

  • better-auth (v2.2.0) - Expanded to 18 framework integrations with 30+ authentication plugins

āš ļø Important: Token Limits

Skill Visibility Constraint

Claude Code has a 15,000 character limit for the total size of skill descriptions in the system prompt. This limit also applies to commands and agents.

What this means:

  • Not all 170 skills may be visible in Claude's context at once
  • Skills are loaded based on relevance and available token budget
  • You can verify how many skills Claude currently sees by asking: "How many skills do you see in your system prompt?"

Checking Visible Skills

To verify which skills are currently loaded:

# Ask Claude Code directly
"Check what skills/plugins you see in your system prompt"

Claude will report something like: "85 of 170 skills visible due to token limits"

Workaround: Increase Token Budget

You can double the headroom for skill descriptions by setting an environment variable:

# Increase limit to 30,000 characters
export SLASH_COMMAND_TOOL_CHAR_BUDGET=30000

# Then launch Claude Code
claude

This gives you approximately 2x more skill visibility in the system prompt.

Note: This is a temporary workaround. The Claude Code team is working on better solutions for skill discovery and loading.

Token Efficiency

MetricManual SetupWith SkillsSavings
Average Tokens12,000-15,0004,000-5,000~65%
Typical Errors2-4 per service0 (prevented)100%
Setup Time2-4 hours15-45 minutes~80%

Across all 170 skills: 400+ documented errors prevented.

Contributing

Prerequisites for Contributors

Install the official plugin development toolkit:

/plugin install plugin-dev@claude-code-marketplace

This provides:

  • /plugin-dev:create-plugin command (8-phase guided workflow)
  • 7 comprehensive skills (hooks, MCP, structure, agents, commands, skills)
  • 2 specialized agents (agent-creator, plugin-validator)

Quick Steps

  1. Create skill directory in plugins/
  2. Add SKILL.md with YAML frontmatter
  3. Run ./scripts/sync-plugins.sh
  4. Submit pull request

See CONTRIBUTING.md and PLUGIN_DEV_BEST_PRACTICES.md for detailed guidelines.

Documentation

DocumentPurpose
START_HERE.mdStart here! Quick navigation guide
PLUGIN_DEV_BEST_PRACTICES.mdRepository-specific best practices (marketplace, budget, quality)
MARKETPLACE.mdFull skill catalog and installation guide
MARKETPLACE_MANAGEMENT.mdTechnical infrastructure (plugin.json, scripts, validation)
CLAUDE.mdProject context and development standards
CONTRIBUTING.mdContribution guidelines

Links

Built with ā¤ļø by Claude Skills Maintainers

View source on GitHub

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