Best Practices

Overview

This guide covers best practices for integrating S2 into your applications, whether using the cloud service or self-hosting S2 Lite.

Connection Management

Reuse SDK Clients

Create SDK clients once and reuse them across your application. Clients maintain connection pools and internal state.

// Good: Create once, reuse everywhere
let s2 = S2::new(S2Config::new(access_token))?;
let basin = s2.basin(basin_name);
let stream = basin.stream(stream_name);

// Use the same client for multiple operations
stream.append(input1).await?;
stream.append(input2).await?;

// Bad: Creating new clients for each operation
for _ in 0..100 {
    let s2 = S2::new(S2Config::new(access_token))?; // Don't do this!
    s2.basin(basin_name).stream(stream_name).append(input).await?;
}

Configure Timeouts

Set appropriate timeouts for your use case:

let config = S2Config::new(access_token)
    .with_timeout(Duration::from_secs(30));

let s2 = S2::new(config)?;

For long-running streaming sessions, use higher timeouts or configure the timeout specifically for read operations.

Basin and Stream Configuration

Enable Auto-Creation

For development and testing, enable automatic stream creation:

s2 create-basin my-basin \
  --create-stream-on-append \
  --create-stream-on-read

In production, disable auto-creation and explicitly create streams. This prevents typos from creating unwanted streams.

Use Descriptive Names

Choose clear, descriptive names for basins and streams:

// Good: Clear purpose
let basin = s2.basin("user-events");
let stream = basin.stream("signup-events");

// Bad: Unclear purpose
let basin = s2.basin("data");
let stream = basin.stream("stream1");

Name Validation

Basin and stream names must:

Be 1-63 characters long
Contain only lowercase letters, numbers, and hyphens
Start and end with a letter or number
Not contain consecutive hyphens

Writing Data

Batch Records

Batch multiple records in a single append for better throughput:

// Good: Batch multiple records
let records = vec![
    AppendRecord::new("event1")?,
    AppendRecord::new("event2")?,
    AppendRecord::new("event3")?,
];
let input = AppendInput::new(AppendRecordBatch::try_from_iter(records)?);
stream.append(input).await?;

// Bad: Individual appends
for event in events {
    let input = AppendInput::new(AppendRecordBatch::try_from_iter([
        AppendRecord::new(event)?
    ])?);
    stream.append(input).await?; // Multiple round trips
}

S2 processes batches atomically - all records in a batch succeed or fail together.

Use the Producer API

For high-throughput scenarios, use the Producer API which handles batching and pipelining automatically:

use s2_sdk::producer::ProducerConfig;

let producer = stream.producer(ProducerConfig::new());

// Submit records and get tickets
let ticket1 = producer.submit(AppendRecord::new("event1")?).await?;
let ticket2 = producer.submit(AppendRecord::new("event2")?).await?;

// Wait for acknowledgments
let ack1 = ticket1.await?;
let ack2 = ticket2.await?;

// Always close the producer when done
producer.close().await?;

The Producer API automatically batches records and uses pipelining for optimal performance.

Handle Errors

Always handle append errors appropriately:

match stream.append(input).await {
    Ok(output) => {
        println!("Appended {} records", output.records.len());
    }
    Err(S2Error::Server(err)) => {
        // Server error - may be retryable
        eprintln!("Server error: {}", err.message);
    }
    Err(S2Error::Client(err)) => {
        // Client error - likely not retryable
        eprintln!("Client error: {}", err);
    }
    Err(err) => {
        eprintln!("Unexpected error: {}", err);
    }
}

Reading Data

Use Streaming Sessions

For continuous reading, use streaming sessions instead of polling:

use futures::StreamExt;

let input = ReadInput::new();
let mut batches = stream.read_session(input).await?;

while let Some(result) = batches.next().await {
    let batch = result?;
    for record in batch.records {
        // Process record
        println!("seq_num: {}, body: {:?}", record.seq_num, record.body);
    }
}

Set Appropriate Read Limits

Control how much data you read:

use s2_sdk::types::{ReadLimits, ReadStop};

let input = ReadInput::new()
    .with_stop(ReadStop::new()
        .with_limits(ReadLimits::new()
            .with_count(100)           // Max 100 records
            .with_bytes(1024 * 1024)   // Max 1MB
        )
    );

let output = stream.read(input).await?;

Use Checkpoints

Store the last processed sequence number to resume reading:

// Read from a specific sequence number
let input = ReadInput::new()
    .with_start_seq_num(last_processed_seq_num + 1);

let output = stream.read(input).await?;

// Process records and update checkpoint
for record in output.records {
    process_record(&record)?;
    last_processed_seq_num = record.seq_num;
    save_checkpoint(last_processed_seq_num)?;
}

S2 Lite Specific

Storage Backend Selection

In-Memory (Development/Testing)

# No persistence - data lost on restart
s2 lite --port 8080

Perfect for integration tests and local development.

Local Disk (Single-Node Development)

# Persists to local disk
s2 lite --port 8080 --local-root /var/lib/s2lite

Local disk mode is not suitable for production as it lacks durability guarantees.

Object Storage (Production)

# AWS S3
s2 lite --bucket my-s3-bucket --path s2lite

# Tigris or other S3-compatible
AWS_ACCESS_KEY_ID=xxx \
AWS_SECRET_ACCESS_KEY=yyy \
AWS_ENDPOINT_URL_S3=https://fly.storage.tigris.dev \
s2 lite --bucket my-bucket --path s2lite

Always use object storage for production deployments to ensure data durability.

Resource Limits

When deploying S2 Lite, set appropriate resource limits:

resources:
  requests:
    memory: "512Mi"
    cpu: "500m"
  limits:
    memory: "2Gi"
    cpu: "2000m"

Environment Variables

SlateDB Configuration

# Flush interval (lower = better latency, more API calls)
SL8_FLUSH_INTERVAL=10ms

For production with object storage, use 50ms (default). For in-memory testing, use 5ms (default).

Performance Tuning

# Enable pipelining (experimental)
S2LITE_PIPELINE=true

Pipelining is currently disabled by default. Only enable in non-critical environments.

Logging

# Production: info or warn level
RUST_LOG=info

# Development: debug level
RUST_LOG=debug

# Specific modules
RUST_LOG=s2_lite=debug,slatedb=info

Deployment Patterns

Single Instance

Simplest deployment for small workloads:

docker run -p 8080:80 \
  -e AWS_PROFILE=${AWS_PROFILE} \
  -v ~/.aws:/home/nonroot/.aws:ro \
  ghcr.io/s2-streamstore/s2 lite \
  --bucket my-bucket \
  --path s2lite

S2 Lite is a single-node binary. For high availability, use the S2 cloud service.

Kubernetes with Helm

helm install s2-lite s2/s2-lite-helm \
  --set objectStorage.enabled=true \
  --set objectStorage.bucket=my-bucket \
  --set metrics.serviceMonitor.enabled=true

Security

Access Tokens

Cloud Service:

# Never commit tokens to version control
export S2_ACCESS_TOKEN=$(cat ~/.s2/token)

S2 Lite:

# Token value is ignored but required
export S2_ACCESS_TOKEN="any-value"

S2 Lite does not validate access tokens. Use network-level security (VPC, firewall rules) to protect your S2 Lite instances.

TLS/HTTPS

For S2 Lite in production, enable TLS:

helm install s2-lite s2/s2-lite-helm \
  --set tls.enabled=true \
  --set tls.cert=/etc/tls/tls.crt \
  --set tls.key=/etc/tls/tls.key

Network Isolation

Deploy S2 Lite in a private network:

# Kubernetes: ClusterIP service (internal only)
service:
  type: ClusterIP
  port: 80

SDK Compatibility

Ensure you’re using compatible SDK versions:

SDK	Minimum Version	S2 Cloud	S2 Lite
CLI	v0.26+	✅	✅
TypeScript	v0.22+	✅	✅
Go	v0.11+	✅	✅
Rust	v0.22+	✅	✅
Python	Migration needed	✅	🚧
Java	Migration needed	✅	🚧

S2 Lite requires the S2-Basin header for stream operations. SDKs handle this automatically.

Performance Optimization

Benchmark Your Workload

Use the built-in benchmark tool:

# Test write performance
s2 bench my-basin/my-stream \
  --target-mibps 10 \
  --duration 30s \
  --catchup-delay 0s

Optimize Batch Sizes

Find the optimal batch size for your workload:

Too small: Higher overhead from API calls
Too large: Higher latency, more memory usage
Recommended: 10-100 records or 10KB-1MB per batch

Monitor Metrics

Track these key metrics:

Append latency (P95, P99)
Batch sizes (records and bytes)
Error rates
Throughput (records/sec, bytes/sec)

Error Handling

Retry Logic

Implement exponential backoff for transient errors:

use tokio::time::{sleep, Duration};

let mut retries = 0;
let max_retries = 3;

loop {
    match stream.append(input.clone()).await {
        Ok(output) => break,
        Err(err) if retries < max_retries => {
            retries += 1;
            let delay = Duration::from_millis(100 * 2u64.pow(retries));
            eprintln!("Retry {} after {:?}: {}", retries, delay, err);
            sleep(delay).await;
        }
        Err(err) => return Err(err.into()),
    }
}

Circuit Breaker Pattern

For high-availability systems, implement circuit breakers to prevent cascading failures.

Testing

Use In-Memory S2 Lite

Always test against in-memory S2 Lite:

# In CI/CD
docker run -d -p 8080:80 ghcr.io/s2-streamstore/s2 lite

Separate Test Basins

Use separate basins for different environments:

let basin = match env::var("ENVIRONMENT") {
    Ok(env) if env == "production" => "prod-events",
    Ok(env) if env == "staging" => "staging-events",
    _ => "dev-events",
};

Clean Up Test Data

#[cfg(test)]
mod tests {
    use super::*;

    async fn cleanup_basin(s2: &S2, basin_name: BasinName) {
        let _ = s2.delete_basin(basin_name).await;
    }

    #[tokio::test]
    async fn test_with_cleanup() {
        let s2 = S2::new(S2Config::new("test-token")).unwrap();
        let basin_name = "test-basin".parse().unwrap();
        
        // Test code...
        
        cleanup_basin(&s2, basin_name).await;
    }
}

Migration and Compatibility

Migrating from Development to Production

Switch from in-memory to object storage
Enable TLS/HTTPS
Disable auto-creation of streams
Configure monitoring and alerting
Set up automated backups (object storage handles this)
Review resource limits

Cloud to Self-Hosted (or vice versa)

Both use the same API, so only configuration changes are needed:

// Cloud
let config = S2Config::new(access_token);

// Self-hosted S2 Lite
let config = S2Config::new("any-token")
    .with_account_endpoint("http://localhost:8080")
    .with_basin_endpoint("http://localhost:8080");

​Overview

​Connection Management

​Reuse SDK Clients

​Configure Timeouts

​Basin and Stream Configuration

​Enable Auto-Creation

​Use Descriptive Names

​Name Validation

​Writing Data

​Batch Records

​Use the Producer API

​Handle Errors

​Reading Data

​Use Streaming Sessions

​Set Appropriate Read Limits

​Use Checkpoints

​S2 Lite Specific

​Storage Backend Selection

​In-Memory (Development/Testing)

​Local Disk (Single-Node Development)

​Object Storage (Production)

​Resource Limits

​Environment Variables

​SlateDB Configuration

​Performance Tuning

​Logging

​Deployment Patterns

​Single Instance

​Kubernetes with Helm

​Security

​Access Tokens

​TLS/HTTPS

​Network Isolation

​SDK Compatibility

​Performance Optimization

​Benchmark Your Workload

​Optimize Batch Sizes

​Monitor Metrics

​Error Handling

​Retry Logic

​Circuit Breaker Pattern

​Testing

​Use In-Memory S2 Lite

​Separate Test Basins

​Clean Up Test Data

​Migration and Compatibility

​Migrating from Development to Production

​Cloud to Self-Hosted (or vice versa)

Overview

Connection Management

Reuse SDK Clients

Configure Timeouts

Basin and Stream Configuration

Enable Auto-Creation

Use Descriptive Names

Name Validation

Writing Data

Batch Records

Use the Producer API

Handle Errors

Reading Data

Use Streaming Sessions

Set Appropriate Read Limits

Use Checkpoints

S2 Lite Specific

Storage Backend Selection

In-Memory (Development/Testing)

Local Disk (Single-Node Development)

Object Storage (Production)

Resource Limits

Environment Variables

SlateDB Configuration

Performance Tuning

Logging

Deployment Patterns

Single Instance

Kubernetes with Helm

Security

Access Tokens

TLS/HTTPS

Network Isolation

SDK Compatibility

Performance Optimization

Benchmark Your Workload

Optimize Batch Sizes

Monitor Metrics

Error Handling

Retry Logic

Circuit Breaker Pattern

Testing

Use In-Memory S2 Lite

Separate Test Basins

Clean Up Test Data

Migration and Compatibility

Migrating from Development to Production

Cloud to Self-Hosted (or vice versa)