Postgres UNION-Based Query Returning Unexpected Null Rows
When a UNION or UNION ALL query in PostgreSQL returns rows with unexpected NULL values in columns that clearly have data in the underlying tables, the cause is...
Blog
All troubleshooting articles, newest first.
Gin CORS Error Blocking React Native Requests
A CORS error between a React Native app and a Gin backend is technically a browser-enforced restriction, but it commonly shows up during development with tools...
Gin Router Returning 404 on Valid Route
When a Gin route returns a 404 even though the handler is clearly registered and the path looks correct, the cause is almost always a subtle mismatch between...
Go GORM Foreign Key Constraint Violation on Insert
A foreign key constraint violation in GORM during an insert almost always means you're trying to save a record that references a parent row which doesn't exist...
Go "Package Not Found" After go mod tidy
Running go mod tidy is supposed to clean up your dependencies, but it can sometimes leave you with a "package not found" error for something that was working...
Go Struct JSON Tags Not Serializing Correctly
When a Go struct doesn't serialize to JSON the way you expect — fields missing entirely, wrong key names, or values that should be omitted but aren't — the...
Docker Build Cache Not Invalidating After File Change
If you change a file in your project but docker build keeps producing an image with the old content, Docker isn't actually ignoring your change — it's reusing...
Docker Compose Network Not Resolving Between Containers
When containers in a Docker Compose setup can't reach each other by name — for example, your app container failing to connect to a database container using its...
Docker Container Can't Connect to Host PostgreSQL
When a containerized application needs to reach a PostgreSQL server running directly on your host machine (not inside another container), connection failures...