# StartOS v0.4.0

## Warning

Previous backups are incompatible with v0.4.0. It is strongly recommended that you (1) immediately update all services, then (2) create a fresh backup. See the [backups](#improved-backups) section below for more details.

## Summary

A server is not a toy. It is a critical component of the computing paradigm, and its failure can be catastrophic, resulting in downtime or loss of data. From the beginning, Start9 has taken a "security and reliability first" approach to the development of StartOS, favoring soundness over speed, and prioritizing essential features such as encrypted network connections, simple backups, and a reliable container runtime over nice-to-haves like custom theming and more services.

Start9 is paving new ground with StartOS, trying to create what most developers and IT professionals thought impossible; namely, an OS and user experience that affords a normal person the same independent control over their data and communications as an experienced Linux sysadmin.

The difficulty of our endeavor requires making mistakes; and our integrity and dedication to excellence require that we correct them. This means a willingness to discard bad ideas and broken parts, and if absolutely necessary, to tear it all down and start over. That is exactly what we did with StartOS v0.2.0 in 2020. It is what we did with StartOS v0.3.0 in 2022. And we are doing it now with StartOS v0.4.0 in 2026.

v0.4.0 is a complete rewrite of StartOS, almost nothing survived. After nearly six years of building StartOS, we believe that we have finally arrived at the correct architecture and foundation that will allow us to deliver on the promise of sovereign computing.

## Changelog

### New User interface

We re-wrote the StartOS UI to be more performant, more intuitive, and better looking on both mobile and desktop. Enjoy.

### Translations

StartOS v0.4.0 supports multiple languages and also makes it easy to add more later on.

### LXC Container Runtime

Neither Docker nor Podman offer the reliability and flexibility needed for StartOS. Instead, v0.4.0 uses a nested container paradigm based on LXC for the outer container and Linux namespaces for sub containers. This architecture naturally supports multi container setups.

### Hardware Acceleration

Services can take advantage of (and require) the presence of certain hardware modules, such as Nvidia GPUs, for transcoding or inference purposes. For example, StartOS and Ollama can run natively on The Nvidia DGX Spark and take full advantage of the hardware/firmware stack to perform local inference against open source models.

### New S9PK archive format

The S9PK archive format has been overhauled to allow for signature verification of partial downloads, and allow direct mounting of container images without unpacking the s9pk.

### Improved Actions

Actions take arbitrary form input and return arbitrary responses, thus satisfying the needs of both "Config" and "Properties", which have now been removed. The new actions API gives package developers the ability to break up Config and Properties into smaller, more specific formats, or to exclude them entirely without polluting the UI. Improved form design and new input types round out the new actions experience.

### Squashfs Images for OS Updates

StartOS now uses squashfs images instead of rsync for OS updates. This allows for better update verification and improved reliability.

### Typescript Package API and SDK

Package developers can now take advantage of StartOS APIs using the new start-sdk, available in Typescript. A barebones StartOS package (s9pk) can be produced in minutes with minimal knowledge or skill. More advanced developers can use the SDK to create highly customized user experiences for their service.

### Removed PostgresSQL

StartOS itself has miniscule data persistence needs. PostgresSQL was overkill and has been removed in favor of lightweight PatchDB.

### Sending Emails via SMTP

You can now add your Gmail, SES, or other SMTP credentials to StartOS in order to send deliver email notifications from StartOS and from installed services that support SMTP.

### SSH password auth

You can now SSH into your server using your master password. SSH public key authentication is still supported as well.

### Tor Address Management

StartOS v0.4.0 supports adding and removing Tor addresses for StartOS and all service interfaces. You can even provide your own private key instead of using one auto-generated by StartOS. This has the added benefit of permitting vanity addresses.

### Progress Reporting

A new progress reporting API enabled package developers to create unique phases and provide real-time progress reporting for actions such as installing, updating, or backing up a service.

### Registry Protocol

The new registry protocol bifurcates package indexing (listing/validating) and package hosting (downloading). Registries are now simple indexes of packages that reference binaries hosted in arbitrary locations, locally or externally. For example, when someone visits the Start9 Registry, the curated list of packages comes from Start9. But when someone installs a listed service, the package binary is being downloaded from Github. The registry also validates the binary. This makes it much easier to host a custom registry, since it is just a curated list of services tat reference package binaries hosted on Github or elsewhere.

### LAN port forwarding

Perhaps the biggest complaint with prior version of StartOS was use of unique .local URLs for service interfaces. This has been corrected. Service interfaces are now available on unique ports, allowing for non-http traffic on the LAN as well as remote access via VPN.

### Improved Backups

The new start-fs fuse module unifies file system expectations for various platforms, enabling more reliable backups. The new system also defaults to using rsync differential backups instead of incremental backups, which is faster and saves on disk space by also deleting from the backup files that were deleted from the server.

### Exver

StartOS now uses Extended Versioning (Exver), which consists of three parts: (1) a Semver-compliant upstream version, (2) a Semver-compliant wrapper version, and (3) an optional "flavor" prefix. Flavors can be thought of as alternative implementations of services, where a user would only want one or the other installed, and data can feasibly be migrating between the two. Another common characteristic of flavors is that they satisfy the same API requirement of dependents, though this is not strictly necessary. A valid Exver looks something like this: `#knots:29.0:1.0-beta.1`. This would translate to "the first beta release of StartOS wrapper version 1.0 of Bitcoin Knots version 29.0".

### Let's Encrypt

StartOS now supports Let's Encrypt to automatically obtain SSL/TLS certificates for public domains. This means people visiting your public websites and APIs will not need to download and trust your server's Root CA.

### Gateways

Gateways connect your server to the Internet, facilitating inbound and outbound traffic. Your router is a gateway. It is now possible to add Wireguard VPN gateways to your server to control how devices outside the LAN connect to your server and how your server connects out to the Internet.

### Static DNS Servers

By default, StartOS uses the DNS servers it receives via DHCP from its gateway(s). It is now possible to override these DNS servers with custom, static ones.

### Internal DNS Server

StartOS runs its own DNS server and automatically adds records for your private domains. You can update your router or other gateway to use StartOS DNS server in order to resolve these domains locally.

### Private Domains

A private domain is like to your server's .local, except it also works for VPN connectivity, and it can be _anything_. It can be a real domain you control, a made up domain, or even a domain controlled by someone else.

Similar to your local domain, private domains can only be accessed when connected to the same LAN as your server, either physically or via VPN, and they require trusting your server's Root CA.

### Public Domains (Clearnet)

It is now easy to expose service interfaces to the public Internet on a public domain you control. There are two options, both of which are easy to accomplish:

1. Open ports on your router. This option is free and supported by all routers. The drawback is that your home IP address is revealed to anyone accessing an exposed interface.

2. Use a Wireguard reverse tunnel, such as [StartTunnel](#start-tunnel) to proxy web traffic. This option requires renting a $5-$10/month VPS and installing StartTunnel (or similar). The result is a new gateway, a virtual router in the cloud, that you can use to expose service interfaces instead of your real router, thereby hiding your IP address from visitors.
