If you're looking for a PluginLab replacement, Kobble is a strong contender. Kobble is an all-in-one platform that includes built-in support for authentication, payments, emailing, and more. It has a no-code authentication portal that supports a wide range of OAuth providers, like PluginLab, and integrates well with modern frameworks like Next.js. The platform also supports payment integration with Stripe and has a tiered pricing system with a free plan and a Pro plan at $25/month.
Another alternative is Staarter, a Next.js SaaS boilerplate designed to accelerate development by providing pre-configured core features for building scalable SaaS projects. Staarter includes strong authentication and authorization, easy subscription management with Stripe, Paddle, or LemonSqueezy, and full localization support. It's a powerful option for entrepreneurs and developers who want to save time and effort setting up a SaaS project, with a single lifetime access payment of $399.