Courier vs Fly.io
Notification API with multi-channel orchestration, templates, and preferences
vs. Run your app close to users, globally
Pricing tiers
Courier
Free
Up to 10,000 notifications/month. All channels. Community support.
Free
Business
From $99/mo. Higher volumes, advanced routing, preference center, branding removal.
$99/mo
Enterprise
Custom. SOC 2, SSO, dedicated support, volume discounts, SLA.
Custom
Fly.io
Pay-as-you-go
No monthly fee. Machines billed per second. Free allocations: ~3 small shared machines + 3 GB volumes.
$0 base (usage-based)
Shared CPU 1x — 256 MB
Entry VM. 1 shared vCPU, 256 MB RAM. ~$2.02/month continuously on.
$2/mo
Performance 1x — 2 GB
Dedicated 1 vCPU, 2 GB RAM.
$32/mo
Reservation — Shared (1 yr)
$36/year for $5/mo credit (40% savings).
$36/mo
Shared CPU 8x — 16 GB
8 shared vCPU, 16 GB RAM.
$89/mo
Performance 16x — 128 GB
Dedicated 16 vCPU, 128 GB RAM.
$1014/mo
Enterprise
Custom. Dedicated capacity, SLA.
Custom
Free-tier quotas head-to-head
Comparing free on Courier vs pay-as-you-go on Fly.io.
| Metric | Courier | Fly.io |
|---|---|---|
| notifications monthly | 10000 notifications/mo | — |
Features
Courier · 13 features
- Chat — Slack, Microsoft Teams, Discord, Mattermost.
- Email — SendGrid, Postmark, Mailgun, AWS SES, Resend, SMTP.
- Inbox (In-App) — React/JS drop-in in-app inbox component.
- Lists — Segment recipients for bulk notification sends.
- Logs + Analytics — Per-message delivery timeline + engagement.
- Multi-channel Routing — Provider failover + preferred channel per user.
- Notification Designer — Visual editor for templates across channels.
- Preferences — Per-user notification preferences hub.
- Push — APNs, FCM, Expo, OneSignal.
- Send API — POST /send with template + recipients + data.
- SMS — Twilio, MessageBird, Vonage, Plivo, Telnyx.
- Templates + Versioning — Template brands, variants, localization, version history.
- Webhooks — Delivery + engagement event webhooks.
Fly.io · 14 features
- Auto Stop/Start — Machines auto-stop when idle, start on request (like scale-to-zero).
- Certs — Let's Encrypt + wildcard certs managed.
- Fly GPU — A100/L40S/A10 on-demand GPU machines.
- Fly Kubernetes (FKS) — Managed Kubernetes on Fly machines.
- Fly Machines — Firecracker microVMs. Start in <1s. Run any Docker image.
- Fly Postgres — Managed Postgres via Supabase partnership (2024). Also legacy self-run Postgres …
- fly-replay headers — Route request to another region at app level.
- Fly Volumes — Persistent SSD attached to a Machine. Encrypted at rest.
- Global Anycast — Single IP routes to the closest region automatically.
- LiteFS — Distributed SQLite with primary/replica across regions.
- Private Networks — 6PN WireGuard mesh. Connect machines across regions privately.
- Secrets — Encrypted env vars propagated to all regions.
- Tigris (partner) — S3-compatible storage for Fly apps. By partner.
- Upstash Redis (partner) — Managed Redis via Upstash.
Developer interfaces
| Kind | Courier | Fly.io |
|---|---|---|
| CLI | Courier CLI | flyctl CLI |
| SDK | courier-go, courier-java, @trycourier/courier, trycourier (Python), @trycourier/react-inbox, trycourier (Ruby) | — |
| REST | Courier REST API | Machines API |
| GRAPHQL | — | Fly GraphQL API |
| OTHER | Courier Studio, Outbound Webhooks | Fly Postgres (wire) |
Staxly is an independent catalog of developer platforms. Some links to Courier and Fly.io may be affiliate links — Staxly may earn a commission if you sign up through them, at no extra cost to you. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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