# missing go.sum entry for module providing package github.com/foo/bar; to add: go mod download github.com/foo/bar

- **ID:** `go/go-sum-missing-entry`
- **Domain:** go
- **Category:** build_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

A dependency was added to go.mod but go.sum was not updated, often due to using -mod=mod without tidy.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 1.16 | active | — | — |
| 1.23 | active | — | — |

## Workarounds

1. **** (95% success)
   ```
   go mod tidy
   ```
2. **** (90% success)
   ```
   go mod download github.com/foo/bar
   ```

## Dead Ends

- **** — This will regenerate all entries but may take time and cause network issues. (40% fail)
- **** — The hash must match exactly; a random hash will cause checksum mismatch. (100% fail)