AI Coding

Roo Code started as a "let's just add a few features" fork of Cline. Eight months later it has its own roadmap, its own community, and a feature set that quietly overtook the parent. Yes really.

The Setup

Roo is a VS Code extension, same lineage as Cline, but with a faster release cadence and custom modes you can define yourself. Want a "designer" mode that only edits Tailwind classes? A "DBA" mode that only touches SQL? You write the prompt, save it as a mode, and switch with a hotkey.

{
  "customModes": [
    {
      "slug": "tailwind-only",
      "name": "Tailwind Only",
      "roleDefinition": "You ONLY edit className strings and Tailwind config. You never edit logic, types, or component structure.",
      "groups": ["edit"],
      "fileRegex": "\\.(astro|tsx|jsx|css)$"
    },
    {
      "slug": "rls-auditor",
      "name": "RLS Auditor",
      "roleDefinition": "You audit Supabase RLS policies. Find tables missing policies. Suggest fixes. Never write app code.",
      "groups": ["read"]
    }
  ]
}

The Money Pattern

Custom modes are absurdly powerful when you scope them tight. I use a "scope-locked" mode on Aidxn Design that can only edit files matching src/pages/blog/*.astro. No more accidental refactors of unrelated files because the agent got curious.

The diff handling is also better — Roo applies smaller, more reviewable patches by default, and the rollback UX is a single click.

The Catch

The cline-fork ecosystem is fragmenting fast. Roo, Cline, Kilo, RA.Aid — each with subtly different prompts and tool schemas. If you switch between them, settings do not transfer and your custom rules need rewriting.

Roo also moves fast enough that breaking changes slip through. Pin your extension version on production-critical projects.

The Verdict

Roo Code is what Cline could have been if it shipped weekly. For anyone who already lives in VS Code and wants real customisation, Roo is the move. The custom modes alone justify the switch — once you scope an agent properly, you stop firefighting and start shipping.