elysia-nginx-500-debug

Diagnose intermittent nginx HTTP 500 errors proxying Elysia.js backends on Bun.

2|Updated May 10, 2026
One-click install
npx skills add https://github.com/freedomw1987/tree_monstor --skill elysia-nginx-500-debug
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: elysia-nginx-500-debug
Source: https://github.com/freedomw1987/tree_monstor/tree/main/skills/elysia-nginx-500-debug
Command: npx skills add https://github.com/freedomw1987/tree_monstor --skill elysia-nginx-500-debug

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This Skill addresses random HTTP 500 errors that occur when Elysia.js (Bun) backends are proxied through nginx, where direct calls to the backend return 200 responses consistently but nginx-proxied requests fail 40-60% of the time with no corresponding nginx error log entries.

Core Features & Use Cases

  • Structured Debugging Workflow: Step-by-step guidance to isolate the root cause of the nginx 500 errors, including checks for backend health, nginx error logs, and masked nginx services.
  • Documented Failed Fixes: Pre-compiled list of common nginx configuration tweaks that do not resolve the issue, saving hours of redundant troubleshooting.
  • Proven Working Solution: Provides a compatible Node.js http module replacement backend code that eliminates the Elysia.js and nginx HTTP/1.1 keepalive compatibility issue causing the failures. Use Case: For development and operations teams running Elysia.js APIs behind nginx, use this Skill to quickly diagnose and resolve intermittent 500 errors without extensive trial-and-error of nginx configurations.

Quick Start

Use the elysia-nginx-500-debug skill to diagnose and fix intermittent HTTP 500 errors affecting your Elysia.js backend proxied through nginx.

Frequently Asked Questions about elysia-nginx-500-debug

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
Why does nginx return intermittent HTTP 500 errors when proxying to an Elysia.js backend?

Nginx returns intermittent HTTP 500 errors due to an HTTP/1.1 keepalive compatibility issue between nginx and the Elysia.js Bun runtime. Direct backend calls succeed, but proxied requests fail randomly when keepalive connections are reused.

How do I debug random 500 errors from nginx with no error logs?

Debug random 500 errors without nginx logs by following a structured workflow to isolate the root cause. This includes checking backend health, verifying nginx error logs, and identifying masked nginx services failing under proxy load.

What is the best way to fix Elysia.js and nginx keepalive compatibility issues?

The best way to fix Elysia.js and nginx keepalive compatibility issues is by replacing the backend with a compatible Node.js http module implementation. This eliminates the intermittent 500 failures without modifying nginx configurations.

Which nginx configuration tweaks are ineffective for resolving random 500 errors?

Ineffective nginx configuration tweaks for resolving random 500 errors include common proxy parameter adjustments. The Skill provides a pre-compiled list of these failed fixes to save hours of redundant troubleshooting.

Can I use this debugging workflow for Elysia.js backends running in production environments?

Yes, you can use this debugging workflow for Elysia.js backends in production and development environments. It diagnoses intermittent 500 errors regardless of the environment by targeting the underlying HTTP/1.1 keepalive issue.