Upgrade to Next.js 16 and ESLint 9 to resolve eslint-config-next peer dependency conflict

[Copilot]

Dependabot's bump of eslint-config-next to 16.0.10 caused deployment failures due to unmet peer dependencies (eslint@>=9.0.0 and next@16.x).

Changes

• Upgraded Next.js: 14.2.24 → 16.0.10
• Upgraded ESLint: ^8 → ^9
• Migrated to ESLint v9 flat config: Created eslint.config.mjs, removed deprecated .eslintrc.json
• Updated lint script: next lint → eslint . (Next.js 16 removed the built-in lint command)

Config Migration

Before (.eslintrc.json):

{
  "extends": "next/core-web-vitals"
}

After (eslint.config.mjs):

import eslintConfigNext from 'eslint-config-next';

export default eslintConfigNext;

The flat config is required in ESLint v9 where .eslintrc.* files are deprecated.

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Project	Deployment	Preview	Comments	Updated (UTC)
dayif-portfolio	Error			Dec 12, 2025 9:17am

[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• fonts.googleapis.com
  • Triggering command: /usr/local/bin/node node /home/REDACTED/work/dayif-portfolio/dayif-portfolio/node_modules/.bin/next build (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)