https://github.com/s2-streamstore/s2
Durable Streams API
https://github.com/s2-streamstore/s2
database durable durable-streams log real-time streaming streamstore
Last synced: about 22 hours ago
JSON representation
Durable Streams API
- Host: GitHub
- URL: https://github.com/s2-streamstore/s2
- Owner: s2-streamstore
- License: mit
- Created: 2025-11-07T20:11:30.000Z (4 months ago)
- Default Branch: main
- Last Pushed: 2026-02-27T19:10:10.000Z (5 days ago)
- Last Synced: 2026-02-27T23:26:21.622Z (5 days ago)
- Topics: database, durable, durable-streams, log, real-time, streaming, streamstore
- Language: Rust
- Homepage: https://s2.dev
- Size: 4.12 MB
- Stars: 439
- Watchers: 3
- Forks: 15
- Open Issues: 16
-
Metadata Files:
- Readme: README.md
- License: LICENSE
- Agents: AGENTS.md
Awesome Lists containing this project
- awesome-github-repos - s2-streamstore/s2 - Durable Streams API (Rust)
README
S2, the durable streams API
[s2.dev](https://s2.dev) is a serverless datastore for real-time, streaming data.
This repository contains:
- **[s2-cli](cli/)** - The official S2 command-line interface
- **[s2-lite](lite/)** - An open source, self-hostable server implementation of the [S2 API](https://s2.dev/docs/api)
- **[s2-sdk](sdk/)** - The official Rust SDK for S2
## Installation
### Homebrew (macOS/Linux)
```bash
brew install s2-streamstore/s2/s2
```
### Cargo
```bash
cargo install --locked s2-cli
```
### Release Binaries (macOS/Linux)
```bash
curl -fsSL https://raw.githubusercontent.com/s2-streamstore/s2/main/install.sh | bash
```
Or specify a version with `VERSION=x.y.z` before the command. See all [releases](https://github.com/s2-streamstore/s2/releases).
### Docker
```bash
docker pull ghcr.io/s2-streamstore/s2
```
## s2-lite
`s2-lite` is embedded as the `s2 lite` subcommand of the CLI. It's a self-hostable server implementation of the S2 API.
It uses [SlateDB](https://slatedb.io) as its storage engine, which relies entirely on object storage for durability.
It is easy to run `s2 lite` against object stores like AWS S3 and Tigris. It is a single-node binary with no other external dependencies. Just like [s2.dev](https://s2.dev), data is always durable on object storage before being acknowledged or returned to readers.
You can also simply not specify a `--bucket`, which makes it operate entirely in-memory (or use `--local-root` to persist to local disk instead).
> [!TIP]
> In-memory `s2-lite` is a very effective S2 emulator for integration tests.
### Quickstart
Here's how you can run in-memory without any external dependency:
```bash
# Using Docker
docker run -p 8080:80 ghcr.io/s2-streamstore/s2 lite
# Or directly with the CLI
s2 lite --port 8080
```
AWS S3 bucket example
```bash
docker run -p 8080:80 \
-e AWS_PROFILE=${AWS_PROFILE} \
-v ~/.aws:/home/nonroot/.aws:ro \
ghcr.io/s2-streamstore/s2 lite \
--bucket ${S3_BUCKET} \
--path s2lite
```
Static credentials example (Tigris, R2 etc)
```bash
docker run -p 8080:80 \
-e AWS_ACCESS_KEY_ID=${AWS_ACCESS_KEY_ID} \
-e AWS_SECRET_ACCESS_KEY=${AWS_SECRET_ACCESS_KEY} \
-e AWS_ENDPOINT_URL_S3=${AWS_ENDPOINT_URL_S3} \
ghcr.io/s2-streamstore/s2 lite \
--bucket ${S3_BUCKET} \
--path s2lite
```
> [!NOTE]
> Point the [S2 CLI](https://s2.dev/docs/quickstart) or [SDKs](https://s2.dev/docs/sdk) at your lite instance like this:
> ```bash
> export S2_ACCOUNT_ENDPOINT="http://localhost:8080"
> export S2_BASIN_ENDPOINT="http://localhost:8080"
> export S2_ACCESS_TOKEN="ignored"
> ```
Let's make sure the server is ready:
```bash
while ! curl -sf ${S2_ACCOUNT_ENDPOINT}/health -o /dev/null; do echo Waiting...; sleep 2; done && echo Up!
```
Install the CLI (see [Installation](#installation) above) or upgrade if `s2 --version` is older than `0.26`
Let's create a [basin](https://s2.dev/docs/concepts) with auto-creation of streams enabled:
```bash
s2 create-basin liteness --create-stream-on-append --create-stream-on-read
```
Test your performance:
```bash
s2 bench liteness --target-mibps 10 --duration 5s --catchup-delay 0s
```
Now let's try streaming sessions. In one or more new terminals (make sure you re-export the env vars noted above),
```bash
s2 read s2://liteness/starwars 2> /dev/null
```
Now back from your original terminal, let's write to the stream:
```bash
nc starwars.s2.dev 23 | s2 append s2://liteness/starwars
```
### Kubernetes Deployment
Deploy `s2-lite` to Kubernetes using Helm. See the [Helm chart documentation](charts/s2-lite-helm/README.md) for installation instructions and configuration options.
### Monitoring
`/health` will return 200 on success for readiness and liveness checks
`/metrics` returns Prometheus text format
### Internals
#### SlateDB settings
[Settings reference](https://docs.rs/slatedb/latest/slatedb/config/struct.Settings.html#fields)
Use `SL8_` prefixed environment variables, e.g.:
```bash
# Defaults to 50ms for remote bucket / 5ms in-memory
SL8_FLUSH_INTERVAL=10ms
```
#### Design
[Concepts](https://s2.dev/docs/concepts)
- HTTP serving is implemented using [axum](https://github.com/tokio-rs/axum)
- Each stream corresponds to a Tokio task called [`streamer`](lite/src/backend/streamer.rs) that owns the current `tail` position, serializes appends, and broadcasts acknowledged records to followers
- Appends are pipelined to improve performance against high-latency object storage
- [`lite::backend::kv::Key`](lite/src/backend/kv/mod.rs) documents the data modeling in SlateDB
> [!TIP]
> Pipelining is temporarily [disabled by default](https://github.com/s2-streamstore/s2/issues/48), and it will be enabled once it is completely safe.
> For now, you can use `S2LITE_PIPELINE=true` to get a sense of what performance will look like.
### Compatibility
- [CLI](cli/) ✅ v0.26+
- [TypeScript SDK](https://github.com/s2-streamstore/s2-sdk-typescript) ✅ v0.22+
- [Go SDK](https://github.com/s2-streamstore/s2-sdk-go) ✅ v0.11+
- [Rust SDK](https://github.com/s2-streamstore/s2-sdk-rust) ✅ v0.22+
- [Python](https://github.com/s2-streamstore/s2-sdk-python) 🚧 _needs to be migrated to v1 API_
- [Java](https://github.com/s2-streamstore/s2-sdk-java) 🚧 _needs to be migrated to v1 API_
### API Coverage
Complete [specs](https://github.com/s2-streamstore/s2-specs/tree/main/s2/v1) are available:
- [OpenAPI](https://s2.dev/docs/api) for the REST-ful core
- [Protobuf](https://buf.build/streamstore/s2/docs/main:s2.v1) definitions
- [S2S](https://s2.dev/docs/api/records/overview#s2s-spec), which is the streaming session protocol
> [!IMPORTANT]
> Unlike the cloud service where the basin is implicit as a subdomain, `/streams/*` requests **must** specify the basin using the `S2-Basin` header. The SDKs take care of this automatically.
| Endpoint | Support |
| --- | --- |
| `/basins` | Supported |
| `/streams` | Supported |
| `/streams/{stream}/records` | Supported |
| `/access-tokens` | Not supported https://github.com/s2-streamstore/s2/issues/28 |
| `/metrics` | Not supported |