# mkcert Zero-Config Local Development TLS Certificate Generator

> mkcert is a zero-configuration CLI tool by Filippo Valsorda that creates locally-trusted development certificates. It automatically installs a local CA in the system root store and generates TLS certificates for localhost, custom domains, and IP addresses without manual PKI management.

- Skill: `agentskillexchange/mkcert-zero-config-local-development-tls-certificate-generat` (Agent Skill)
- Install (CLI): `npx skillmds@latest add agentskillexchange/mkcert-zero-config-local-development-tls-certificate-generat`
- Raw SKILL.md: https://api.skillmd.com/api/skills/agentskillexchange/mkcert-zero-config-local-development-tls-certificate-generat/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: agentskillexchange (https://skillmd.com/u/agentskillexchange)
- Updated: 2026-09-08
- Page: https://skillmd.com/skills/agentskillexchange/mkcert-zero-config-local-development-tls-certificate-generat

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# mkcert Zero-Config Local Development TLS Certificate Generator

mkcert is a zero-configuration CLI tool by Filippo Valsorda that creates locally-trusted development certificates. It automatically installs a local CA in the system root store and generates TLS certificates for localhost, custom domains, and IP addresses without manual PKI management.

## Installation

Use the upstream install or setup path that matches your environment:
- brew install mkcert
- brew install nss # if you use Firefox
- git clone https://github.com/FiloSottile/mkcert && cd mkcert

Requirements and caveats from upstream:
- mkcert is a simple tool for making locally-trusted development certificates. It requires no configuration.
- The local CA is now installed in the Firefox trust store (requires browser restart)! 🦊
- or build from source (requires Go 1.13+)

Basic usage or getting-started notes:
- $ mkcert example.com "*.example.com" example.test localhost 127.0.0.1 ::1
- "example.com"
- "*.example.com"

- Source: https://github.com/FiloSottile/mkcert
- Extracted from upstream docs: https://raw.githubusercontent.com/FiloSottile/mkcert/HEAD/README.md

## Source

- [Agent Skill Exchange](https://agentskillexchange.com/skills/mkcert-local-dev-tls-certificate-generator/)