Claude Code .claudeignore: stop leaking secrets and node_modules into your context

Claude Code .claudeignore: stop leaking secrets and node_modules into your context If you've ever watched Claude Code read through thousands of lines of node_modules or seen it suggest changes to your .env file, you've hit one of the most overlooked configuration problems in Claude Code setups. The fix is a .claudeignore file — and most developers don't know it exists. What Claude Code reads by default When you run Claude Code in a project directory, it can access everything in that directory. That includes: node_modules/ — millions of lines of vendor code .env — your API keys, database passwords, secrets dist/ and build/ — compiled output you don't want edited *.log files — debug noise .git/ internals — usually irrelevant This burns through your context window fast and introduces security risks when Claude has visibility into secret files. .claudeignore syntax The .claudeignore file uses the same syntax as .gitignore: # .claudeignore node_modules/ dist/ build/ .next/ .nuxt/ coverage/