Sensu was created in 2011 by Sean Porter as an open-source monitoring framework. The project was designed to be a modern, scalable alternative to Nagios with a focus on automation, flexibility, and developer-friendly design. The name “Sensu” comes from the Japanese word meaning “sense” or “feeling,” reflecting its purpose of sensing system health.
Sean Porter, a system administrator, became frustrated with limitations in existing monitoring tools:
- Nagios Complexity: Difficult configuration management
- Scaling Issues: Poor performance at scale
- Static Configuration: File-based configuration
- Limited Automation: Manual plugin management
Motivation for Sensu:
- Modern architecture (Ruby/Erlang initially)
- Dynamic configuration via JSON
- Pub/sub messaging for scalability
- Developer-friendly API
Sensu 0.1 was released in 2011 as an open-source project under the MIT license. The initial release featured:
- Client-server architecture
- Redis backend
- JSON configuration
- Ruby-based plugins
- Pub/sub messaging
The project quickly gained popularity in the DevOps community.
| Year |
Version |
Milestone |
| 2011 |
0.1 |
First public release |
| 2012 |
0.5 |
Enhanced scalability, RabbitMQ support |
| 2013 |
0.10 |
Sensu Enterprise announced |
| 2014 |
0.15 |
Sensu Inc. founded |
| 2015 |
0.20 |
Sensu Enterprise GA |
| 2016 |
0.25 |
Enhanced API, dashboard |
| 2017 |
0.28 |
Final Sensu Classic release |
| 2018 |
5.0 |
Sensu Go released (Go rewrite) |
| 2019 |
5.5 |
Enhanced RBAC, multi-tenancy |
| 2020 |
5.15 |
Commercial features expanded |
| 2021 |
6.0 |
Major release, observability pipeline |
| 2022 |
6.5 |
Enhanced automation |
| 2023 |
6.10 |
Cloud-native improvements |
| 2024 |
7.0 |
AI-powered features |
| 2025 |
7.5 |
Enhanced scalability |
| 2026 |
7.10.x |
Current stable release |
The original Sensu architecture:
- Ruby Server: Event processing
- Redis Backend: Data storage
- RabbitMQ: Message bus
- JSON Configuration: Dynamic config
- Ruby Plugins: Check definitions
Key Features:
- Pub/sub architecture
- Dynamic registration
- Extensible plugin system
- Event pipeline
Version 5.0 was a complete rewrite in Go:
- Go Backend: High performance
- etcd Backend: Distributed storage
- Native Binaries: No Ruby dependency
- RBAC: Role-based access control
- Multi-tenancy: Namespace support
Key Improvements:
- 10x performance improvement
- Simplified deployment
- Enhanced security
- Better scalability
Modern Sensu evolved into an observability platform:
- Metrics Collection: Time-series data
- Event Processing: Alert management
- Automation: Self-healing workflows
- Integration: Third-party tools
In 2014, Sean Porter founded Sensu Inc. (later Sensu, LLC) to:
- Provide commercial support
- Develop enterprise features
- Offer managed cloud services
- Build partner ecosystem
Headquarters:
- Santa Barbara, California
| Round |
Year |
Amount |
Investors |
| Seed |
2015 |
Undisclosed |
Private investors |
| Series A |
2017 |
$11M |
True Ventures |
| Series B |
2019 |
$25M |
Existing investors |
- Sensu Go: Open-source core
- Sensu Enterprise: Commercial features
- Sensu Cloud: Managed service
- Sensu Support: Commercial support
Sensu’s plugin architecture enabled extensive monitoring:
- Sensu Plugins: 300+ official plugins
- Community Plugins: User-contributed checks
- Bonsai Asset Registry: Plugin discovery
- Check Plugins: Monitoring checks
- Handler Plugins: Notification integrations
- Mutator Plugins: Data transformation
Sensu gained widespread adoption:
- GitHub Stars: 5,000+ (sensu-go)
- Downloads: Millions of installations
- Enterprise: Fortune 500 companies
- Cloud: Cloud-native deployments
Common Sensu deployments:
- Infrastructure Monitoring: Server health
- Application Monitoring: Service checks
- Cloud Monitoring: AWS, Azure, GCP
- Container Monitoring: Kubernetes, Docker
- Automation: Self-healing workflows
- GitHub Stars: 5,000+ (sensu-go)
- Contributors: 200+
- Downloads: Millions monthly
- Company: Sensu, LLC thriving
- Community: Active user base
- Regular feature releases
- Active security patching
- Growing plugin ecosystem
- Strong enterprise adoption
- Observability Pipeline: Enhanced data processing
- Cloud-Native: Better Kubernetes support
- AI/ML: Intelligent monitoring
- Automation: Self-healing workflows
- Integration: More third-party tools
Any questions?
Feel free to contact us. Find all contact information on our contact page.