Lockfile conflicts: resolving merge conflicts in package-lock.json and pnpm-lock.yaml

After merging two feature branches, the lockfile (package-lock.json or pnpm-lock.yaml) has git conflict markers. Committing the conflicted lockfile breaks installs for the whole team.

Never manually edit lockfile conflict markers. Let the package manager regenerate it.

# For package-lock.json (npm)
git checkout package.json # take 'theirs' or 'ours' — reconcile manually
npm install # npm regenerates the lockfile from package.json
git add package-lock.json

# For pnpm-lock.yaml
git checkout package.json # same — reconcile package.json first
pnpm install # pnpm regenerates pnpm-lock.yaml
git add pnpm-lock.yaml

# For yarn.lock
git checkout yarn.lock # take one version
yarn install --frozen-lockfile=false # or just: yarn install
git add yarn.lock

Lockfiles are machine-generated and their internal format encodes a full dependency graph with hashes. Manual resolution of conflict markers almost always produces an invalid or inconsistent graph. Regenerating from package.json is the only safe approach.

Resolving git merge conflicts after parallel branches both modified dependencies