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Frontend Glossary

Frontend engineering · Debugging

Source Map

Also called: Source maps, Debug mapping, .map files

Map minified, bundled code back to original source lines so production stack traces and local debugging stay readable.

In detail

Production JS is minified and merged; stacks become opaque. A source map tells the browser or error tracker that "bundle line 1 col 28403 is Button.tsx line 42."

Don't leak maps on a public CDN if you care about hiding source. Upload them to your error service, or enable maps only in preview.

Dev almost always has maps on; production needs an explicit setting.

Developer info
Term ID
eng-sourcemap
DOM selectors
No DOM cues. This concept isn't detected directly on a page.
Priority
1 · when several match at the same level, the higher priority wins
Version
v1 · updated Oct 5, 2026