Why Open Source
A note from Reloop Labs
2026
Linux, Postgres, Redis, Nginx: the boring foundations of the internet are open. Email sits in that category. If it fails, users can't log in, can't reset passwords, and can't get receipts.
Open source is how we make the four things above credible. You can read how delivery works. You can leave without rewriting your notification stack. The roadmap gets shaped by people shipping real mail, not only by a pricing page.
We're not open-sourcing a demo. Reloop Cloud and Reloop open source are the same product—same APIs whether you use hosted or self-host.
Our commitments.
Four architectural guarantees that govern every release we ship.
License
Apache 2.0
Permissive, public, and self-hostable
Codebase parity
1:1 parity
Identical engine on hosted and self-hosted
Routing auditability
100% public
Deliverability logic verified in source
Vendor lock-in
Zero
Migrate or self-host at any time
The operational difference.
Closed platforms ask you to trust uninspectable routing. Open source lets you verify every delivery decision in code.
Routing and deliverability
Proprietary closed source
Proprietary black-box algorithms. You cannot inspect why a message was throttled, deferred, or rerouted.
Reloop open source
Deterministic routing rules and retry schedules. Every delivery decision is traceable in public source code.
Deployment freedom
Proprietary closed source
SaaS multi-tenant cloud only. Cannot run inside your internal VPC, private subnet, or on-premise hardware.
Reloop open source
Deploy via Docker Compose, Kubernetes, or bare metal on your own infrastructure, or use managed reloop.sh.
Data sovereignty and privacy
Proprietary closed source
All recipient addresses, email bodies, headers, and transmission logs reside on vendor-controlled servers.
Reloop open source
Zero data leaves your VPC when self-hosted. Total control for strict compliance (GDPR, HIPAA, SOC 2).
Incident triage and debugging
Proprietary closed source
Refresh a public status page and wait for level-1 support ticket responses during active outages.
Reloop open source
Inspect application logs, verify queue states in Redis, trace the source code, and reproduce issues locally.
Scaling economics
Proprietary closed source
Volume-tiered billing curves with steep step-up pricing that penalizes high-throughput application growth.
Reloop open source
Predictable flat compute costs on your own hardware, or transparent volume tiers on reloop.sh.
Codebase integrity
Proprietary closed source
Dual-tier models where advanced deliverability features and dedicated IP tooling require enterprise sales calls.
Reloop open source
Single public monorepo. Every feature is released under Apache 2.0 with zero hidden enterprise forks.
Full licensing specifications are available in our Apache 2.0 license document.
One engine. Two deployment paths.
Deploy on your own infrastructure or use our managed edge cloud. Both run the exact same open-source codebase.
Sovereign data & VPCs
Reloop Self-Hosted
Deploy with Docker Compose, Kubernetes, or bare metal. Total control over data residency, custom SMTP egress IPs, and internal VPC routing.
Zero DevOps overhead
Reloop Hosted (reloop.sh)
Global edge API with automated SPF, DKIM, and DMARC verification, managed deliverability pools, and 3,000 free emails every month.
Keep up to date.
Get the latest updates on what we're building.
Ready to build on transparent email?
Reloop is Apache 2.0 open-source. Self-host on your servers or start free on reloop.sh.