P42+ Your JavaScript Assistant for Legacy Code.

Safely modernize and enhance complex, legacy JavaScript and TypeScript codebases. With P42+ for GitHub.

P42 Programming Assistant
"P42 helps us keep the code of our various Vega repositories consistently up to date with modern JavaScript and TypeScript standards."
Dominik Moritz
Co-creator of Vega
P42+ shows you where in your codebase old code is hidden.

Identify Outdated Code

Codebases evolve over many years, and not every part is new and shiny. Often old patterns, outdated best practices, and tech debt accumulate in many areas.

P42+ scans and visualizes your codebase, so you can identify and prioritize problematic code areas for modernization before they lead to developer frustration, missed deadlines, and unnecessary bugs.

P42+ upgrades your codebase while you relax.

Modernize Your Codebase

It is dull and painful to migrate an existing codebase to follow new patterns and use new syntax - and it can take weeks and months.

With P42+, you can apply code migrations to your files and folders in bulk in the VS Code extension and review and test the changes immediately in your development environment. Upgrading your code has never been this easy.

P42+ reviews code together with another developer.

Automate Code Reviews

Pull requests are a great way to exchange knowledge and ensure high code quality. However, experienced engineers should focus on the big picture and not waste time reviewing code quality details repeatedly.

P42+ reviews your pull requests automatically and suggests improvements that make your code cleaner and more modern, so you and your teammates can learn the latest best practices, enjoy high-quality code, and save time.

P42 helps you accelerate your software development.

Speed Up Development

Working with code written with old syntax and patterns from 5 or 10 years ago requires a taxing mental shift for experienced developers. It is even harder for new developers who have not been part of that phase of the JavaScript ecosystem.

P42+ helps you keep your codebase modern and consistent. It makes it easy to onboard new developers, allows you to leverage new tooling for the current syntax, and prevents slowdowns caused by inconsistencies.

"Legacy code is a growing problem in the JavaScript world. I've created P42 to help developers modernize code easily, so they can enjoy implementing new features with the latest standards."
Lars Grammel
Founder of P42

P42+ Plans for All Developers

Open Source
for public repositories
code analysis
bulk code upgrade
automated code review
up to 25 public repositories
for personal repositories
code analysis
bulk code upgrade
automated code review
up to 50 public and personal repositories
per active contributor
for organization repositories
code analysis
bulk code upgrade
automated code review
up to 200 public and organization repositories
per active contributor
for custom requirements
code analysis
bulk code upgrade
automated code review
all repositories
custom extensions and integrations
Individual contract
All prices in US dollars. VAT may apply depending on your location. Every contributor who makes at least 1 commit to a private repository during the billing period is counted as an active contributor. Maximum bare repository size 500MB.

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