How to self-host your Retool alternative
Replacing a self-hosted internal-tools builder splits teams by their actual workflow: code-first, or visual-interface-first. The catalog's 3 alternatives split exactly along that line.
Tools that meet this intent
Alternative to Retool
Scripts, workflows and internal dashboards, a self-hostable alternative to Retool.
Alternative to Retool, Airtable
Low-code builder for internal apps, an alternative to Retool.
Alternative to Retool, PowerApps
Low-code editor for internal dashboards, a direct alternative to Retool.
Real server requirements
Between 256MB and 1GB of RAM depending on the tool — never a single number.
Windmill, as the project itself specifies, "runs real code, not just visual low-code": you write scripts in Python, TypeScript or Go, and it generates panels and flows from there. Budibase and Appsmith are visual drag-and-drop editors — Appsmith, in fact, is described in the catalog as "very similar to Retool" in how it works.
As a practical consequence of those different architectures, each uses a different database engine for its own metadata: Windmill on PostgreSQL, Budibase on CouchDB (a document database uncommon in this catalog), and Appsmith on MongoDB — running each means getting familiar with a different engine, not just a different tool interface.
What you gain and lose versus the SaaS
The choice comes down to what profile the team has: real code (Windmill) requires someone who can program, in exchange for full control over what gets built; a purely visual editor (Budibase, Appsmith) lets you prototype without writing code, at the cost of hitting a wall when you need something the editor doesn't cover.