Introduction

What is Switchflag?

Switchflag gives you a full-stack feature flagging system: a dashboard to manage flags, an SDK to evaluate them, and observability to see what's happening. Flags are fetched once and evaluated client-side, so there's no network round-trip on every getFlag() call.

Key Features

• Targeting rules — 10 operators (equals, contains, startsWith, in, percent, etc.) evaluated in order, first match wins
• Percentage rollouts — Consistent hashing ensures the same user always lands in the same bucket
• Multi-environment — Each flag has independent configuration per environment (development, staging, production)
• Multi-tenant — Organization-based access control with owner/admin/member roles and email invitations
• Audit logging — Every flag change is recorded with who changed what and when
• Type-safe SDK — Zod schemas as the single source of truth for both runtime validation and TypeScript types

How It Works

1. Create a project and define your feature flags in the dashboard
2. Configure targeting rules and rollout percentages per environment
3. Install the SDK in your application
4. Evaluate flags client-side with zero network overhead per call

import { createClient } from '@switchflag/sdk'

const client = createClient({ apiKey: 'sf_production_...' })

const result = await client.getFlag<boolean>('new-checkout-flow', {
  userId: 'user-123',
  country: 'GB',
})

if (result.value) {
  // show new checkout
}

Architecture

The SDK ships in two variants:

• Standard — In-memory Map cache, suited for long-lived server processes
• Edge — Uses fetch with cache: 'force-cache' and next: { revalidate: 60 }, delegating caching to the edge network since edge functions are ephemeral

Next Steps