10 Open Source SaaS Tools That Could Help You Build the Next Big Thing

I'm really glad investors and big companies are finally betting on open source projects. 10 years ago it was hard to imagine there would be so many SaaS products built on an open source model.

Here's a list of my favorites, which can help you set up a great modern architecture and cover different aspects of product development and architecture.

Hasura

Instant, blazing-fast, real-time GraphQL APIs on top of your database, with granular access control and webhooks triggered by database events.

Hasura simplifies development enormously. How do you usually build your applications? You probably pick a framework, set up an ORM, build the database, write migrations by hand, then create a bunch of CRUD endpoints with REST or GraphQL, and add an authorization layer.

With Hasura you can:

• easily create most of your tables in PostgreSQL, TimescaleDB, MySQL, MongoDB or MSSQL from a very convenient interface
• log every change to the database structure as a migration (so you can easily run it in your CI with the Hasura CLI)
• automatically get the GraphQL/REST endpoints corresponding to each table
• protect each endpoint with a powerful set of rules per user role
• and, if you need more business logic, combine the generated endpoints with your own GraphQL server

TimescaleDB

An open source time-series SQL database, optimized for fast inserts and complex queries. It's distributed as a PostgreSQL extension.

A PostgreSQL extension that supercharges time-series performance. Very easy to use, with excellent documentation and a solid cloud offering. You can always use it as a drop-in replacement for PostgreSQL, since it has no downsides, and if you start storing metrics or statistics in your database, you'll already have it covered. For time-series data, its queries run 10 to 100 times faster than plain PostgreSQL.

Supertokens

Open source alternative to Auth0 / Firebase Auth / AWS Cognito

Every project needs authorization. If you've used Auth0, this is practically the same thing, but open source, so you can easily self-host it on your own infrastructure or use the cloud version. It works with JWT, so it integrates seamlessly with Hasura.

n8n

A free, fair-code licensed, node-based workflow automation tool. Easily automate tasks across different services.

Don't feel like coding integrations between services and burning hours on it? Try n8n. It has a powerful interface for designing integrations and automations that respond to data changes or triggers.

Rancher

A complete container management platform

Modern applications deserve modern infrastructure, and managing it can be a nightmare. Rancher simplifies managing Kubernetes clusters, whether you run them in the cloud or on bare-metal servers.

Drone CI

Drone is a container-native continuous delivery platform

While GitHub Actions and GitLab are very popular solutions, Drone CI has a fantastic architecture and a very simple setup. After being acquired by Harness, it got a major update, 2.0.0, with plenty of interesting new features, like activity graphs, user management and a new interface. Drone CI is a very powerful and flexible tool.

Grafana

The open, composable observability and data visualization platform. Visualize metrics, logs and traces from multiple sources, such as Prometheus, Loki, Elasticsearch, InfluxDB, Postgres and many more.

You can't build the next big thing without a good monitoring and analytics solution. Grafana has long been an essential tool in this space, and now it also has a cloud version.

K6

A modern load testing tool, built with Go and JavaScript

The best performance testing tool out there, and it's open source too. Grafana Labs recently acquired K6, so it's sure to get even better. If you've ever written scripts for jMeter, the experience with K6 will feel a hundred times better.

Sentry

Sentry is a cross-platform application monitoring platform focused on error reporting.

Error reporting is key if you want to fix your customers' problems before they impact your business. With Sentry, you just need to integrate their SDK into your framework or language to start getting alerts when errors occur, whether on the client or the server.

Flagsmith

Open source feature flag and remote config service.

By now, you should stop shipping big updates to all users at once. Manage their expectations and get ahead of problems with feature flags. All you need to do is integrate it into your framework via its SDK and decide who gets access to each feature.

Summary

Building projects with open source technologies is fantastic, because you don't need to spend a fortune to try things out, and as the project grows, you can always move to the paid cloud versions.

What open source SaaS do you use in your project?