Flags SDK
Free open-source Vercel library for Next.js and SvelteKit feature flags. Framework-native, provider-agnostic with adapters for LaunchDarkly, Statsig, Optimizely, Hypertune, ConfigCat, DevCycle and Flipt.
Our Verdict
Essentially required glue for feature flags in Next.js; pair it with a real flag provider of your choice.
Pros
- Framework-native for Next.js and SvelteKit
- Provider-agnostic with adapters for major flag SaaS
- Free and open source
- Handles server/edge evaluation cleanly
Cons
- Only a client/framework layer; you still need a provider
- Best DX when also hosting on Vercel
- Limited value outside Next/SvelteKit
- Some adapters lag upstream feature parity
When to Use Flags SDK
Good fit if you need
- Framework-native feature flags for Next.js and SvelteKit
- Provider-agnostic adapters for LaunchDarkly and Statsig
- Edge-compatible flag evaluation without latency penalty
- A/B testing built into Vercel deployment previews
Pricing
Price wrong?Flags SDK Pricing
- Pricing Model
- free
- Free Tier
- Yes
- Entry Price
- —
- Enterprise Available
- No
- Transparency Score
- —
Beta — estimates may differ from actual pricing
Estimated Monthly Cost
$25
Estimated Annual Cost
$300
Estimates are approximate and may not reflect current pricing. Always check the official pricing page.
Project Health
Health Score
3
3 days
6d
21
N/A
MIT
Last checked: 2026-04-21
Lock-in Assessment
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