michalwolanin/noslow

noslow is a TypeScript library for Node.js that watches your database queries and sends you an alert when it finds a problem. You add it to your existing PostgreSQL or MySQL setup with a single line of code, and from that point on it measures every query your app runs. When a query is too slow, runs too many times in a short window, or scans an entire table without using an index, noslow logs the issue to the console with the specific problem and a ready-to-paste SQL fix. For example, if a query takes 847 milliseconds and there is no index on the column being searched, noslow tells you which column needs an index and provides the CREATE INDEX statement. By default it uses built-in rules to detect four patterns: slow queries (over 500 milliseconds), N+1 patterns (the same query running more than five times within a second), full table scans (a SELECT without a WHERE clause), and likely missing indexes on filtered columns. If you want more detailed analysis, you can switch to cloud mode, which sends your sanitized query to Claude Haiku for interpretation, or local mode, which uses an Ollama model running on your own machine with no internet connection. Privacy is built in from the start. Before anything is logged or sent anywhere, the library strips all actual values from the SQL, replacing them with question marks. Email addresses, IDs, and passwords never appear in logs or alerts. Sending alerts to Slack, Discord, Teams, or Telegram is optional and only active if you configure a webhook URL. Adding noslow to an existing Node.js project requires one npm install and two lines of code. The library needs Node 18 or later. The license is MIT.