Stop 04 · Git & Version ControlTopics · 4/8

Merge Conflicts

In short

Two people changed the same line, and Git refuses to guess who's right. That's a merge conflict. It looks scary the first time, but it's just Git asking you a question.

When two branches change the same lines of a file differently, Git can't automatically merge them — resolving conflicts calmly and correctly is a routine skill, not an emergency.

The mascot at a printing shop holds two versions of a decorated wedding card side by side.

Think of it like this

Two edits on the wedding card

Your mausi changed the venue on the invitation card. Your chacha changed the time on the very same line. The printer stops and asks: which line do I print? You read both, maybe keep both changes, and hand back one final version. That's resolving a conflict.

Watch it happen

Reading a conflict in deploy.yaml

<<<<<<< HEAD

replicas: 3

=======

replicas: 5

>>>>>>> scale-up

image: app:1.4

1/5Between <<<<<<< HEAD and ======= is your branch's version: 3 replicas.

The big ideas

What you need to know

Conflicts are normal

They only mean two changes touched the same lines. Nothing is broken and nothing is lost.

Ask the other author

If you don't understand their change, ask before deleting it. A two-minute chat beats a wrong guess.

Pull main often

Merging main into your branch daily keeps conflicts small and easy instead of huge and scary.

Test after resolving

A merge can be correct line by line but wrong as a whole. Run tests or a dry run before pushing.

See it in code

Walk through the code

bash

1git switch feat/scale-up2git merge main3# CONFLICT (content): Merge conflict in deploy.yaml4 5git status                 # lists conflicted files6# edit deploy.yaml, remove the markers, keep the right lines7git add deploy.yaml8git commit                 # completes the merge9 10git merge --abort          # or: give up and go back

1/3Bring main into your branch. Git merges what it can and reports the file it can't.

VS Code and most editors show 'Accept current', 'Accept incoming' and 'Accept both' buttons right above conflict markers.

Save yourself the pain

Common mistakes

Oops

Committing a file that still has <<<<<<< markers in it.

Do this instead

Search the file for <<<<<<< before you git add. Many CI linters also fail on leftover markers.

Oops

Picking 'accept mine' on every conflict to make it go away fast.

Do this instead

Read both sides each time. Blindly keeping yours silently throws away a teammate's fix.

Your mission

Make and fix a conflict

~15 min

Quick check

Git reports a conflict in config.yaml. What should you do first?

Go deeper

1Deliberately create a merge conflict between two branches and practice resolving it.
2Learn to read conflict markers (<<<<<<<, =======, >>>>>>>) and choose the correct resolution.
3Understand why frequent small merges reduce conflict frequency and severity.