Ionic App Upgrade

Upgrade an Ionic Framework app to a newer major version (4 to 5, 5 to 6, 6 to 7, or 7 to 8).

Prerequisites

Target Version	Angular	React	Vue
5	8.2+	16+	N/A
6	12+	17+	3.0.6+
7	14+	17+	3.0.6+
8	16+	17+	3.0.6+

Procedures

Step 1: Detect Current Version

Read @ionic/angular, @ionic/react, or @ionic/vue version from package.json (dependencies or devDependencies). Determine the current major version and which framework is in use (Angular, React, Vue, or Core/Standalone).

Ask the user for the target version. Default to the latest (8) if not specified.

Step 2: Execute Upgrade

For each major version jump between the current and target version, apply the corresponding upgrade guide sequentially:

Current to Target	Reference
4 to 5	references/upgrade-v4-to-v5.md
5 to 6	references/upgrade-v5-to-v6.md
6 to 7	references/upgrade-v6-to-v7.md
7 to 8	references/upgrade-v7-to-v8.md

For multi-version jumps (e.g., 5 to 8), apply each upgrade in order:

1. Read and apply references/upgrade-v5-to-v6.md
2. Build the project (npm run build), fix any errors, and verify the app runs
3. Read and apply references/upgrade-v6-to-v7.md
4. Build the project (npm run build), fix any errors, and verify the app runs
5. Read and apply references/upgrade-v7-to-v8.md
6. Build the project (npm run build), fix any errors, and verify the app runs

Do not skip intermediate versions.

Step 3: Final Verification

After completing all upgrade steps:

npm run build

If the project uses Capacitor, also run:

npx cap sync

Error Handling

• If npm run build fails after an upgrade step, check the compiler errors. Most errors are caused by removed component properties, renamed CSS variables, or changed event handler signatures documented in the reference files.
• If Jest or unit tests fail, check the transformIgnorePatterns configuration — Ionic 6+ ships as ES Modules and requires Babel/Jest configuration updates.
• If CSS styles break after upgrade, check for removed CSS Shadow Parts and renamed CSS variables in the reference file for that version.
• If a multi-version upgrade fails mid-way, fix the current version step before proceeding to the next.
• If the project also uses Capacitor and platform builds fail, the Capacitor version may also need upgrading — use the capacitor-app-upgrades skill.

Related Skills

• capacitor-app-upgrades — If Capacitor also needs upgrading alongside Ionic, use this skill for the Capacitor-specific upgrade steps.
• ionic-app-development — General Ionic development guidance.
• capacitor-plugins — For installing or reconfiguring plugins after the app upgrade.