---

⚡ 30-Second Quick Start

``bash
npm install reseolio
`

`typescript
import { Reseolio } from 'reseolio';

const reseolio = new Reseolio({
storage: 'postgres://user:pass@localhost:5432/mydb'
});

await reseolio.start();

// Make any function durable with one wrapper
const sendEmail = reseolio.durable(
'notifications:email:send',
async (to: string, subject: string) => {
await emailService.send(to, subject);
return { sent: true };
}
);

// Call it like a normal function - it's now crash-proof!
const handle = await sendEmail('user@example.com', 'Welcome!');
const result = await handle.result(); // { sent: true }
`

That's it. Your function now survives crashes, has automatic retries, and can be tracked.

---

🚀 Why Reseolio?

$3


Server crashed? Deployment rolled back? kill -9? Reseolio doesn't care. Your jobs pick up exactly where they left off.

$3

`typescript
// Looks like normal code, but it's crash-proof and distributed
const result = await generatePDFReport(data);
`

$3

No Redis. No RabbitMQ. No message broker cluster. Just your existing PostgreSQL and a single binary.

---

✨ Features

| Feature | Description |
|---------|-------------|
| 🔄 Smart Retries | Exponential, linear, or fixed backoff with jitter |
| 🆔 Idempotency | Built-in deduplication prevents duplicate jobs |
| 🌍 Global State | PostgreSQL-backed, accessible from any node |
| 📊 Observability | Query job status, history, and results via API |
| ⚡ Low Overhead | ~6ms enqueue latency, ~5MB sidecar memory |
| 🔌 Polyglot | Language-agnostic gRPC protocol |

---

📊 Benchmarks

| Metric | Avg (ms) | P95 (ms) |
|--------|----------|----------|
| Enqueue | 6.23 | 9.57 |
| Scheduling Lag | 8.39 | 10.10 |
| Full Round-Trip | 9.85 | 11.50 |

---

📚 Examples

$3

`typescript
const sendEmail = reseolio.durable(
'notifications:email:send',
async (to: string, subject: string) => {
await emailService.send(to, subject);
}
);

// Returns immediately - email is guaranteed to be sent
await sendEmail('user@example.com', 'Welcome!');
`

$3

`typescript
const processPayment = reseolio.durable(
'orders:payment:charge',
async (orderId: string) => {
await paymentGateway.charge(orderId);
return { charged: true };
},
{
maxAttempts: 5, // Retry up to 5 times
backoff: 'exponential', // exponential | linear | fixed
initialDelayMs: 1000, // Start with 1s delay
timeoutMs: 30000, // 30s timeout per attempt
}
);
`

$3

`typescript
// Each step is independently durable
const chargePayment = reseolio.durable('orders:payment:charge', ...);
const reserveInventory = reseolio.durable('orders:inventory:reserve', ...);
const createShipping = reseolio.durable('orders:shipping:create', ...);

// Orchestrator chains them
const processOrder = reseolio.durable(
'orders:fulfillment:process',
async (orderId: string) => {
const payment = await chargePayment(orderId);
await payment.result();

const inventory = await reserveInventory(orderId);
await inventory.result();

const shipping = await createShipping(orderId);
await shipping.result();

return { status: 'fulfilled' };
}
);
`

$3

`typescript
// Even if called 10 times, only runs once per orderId
await processPayment(amount, {
idempotencyKey: charge-${orderId}
});
`

---

📖 API Reference

$3

| Option | Type | Default | Description |
|--------|------|---------|-------------|
| storage | string | required | PostgreSQL connection string |
| workerConcurrency | number | 10 | Max concurrent job executions |
| namespace | string | 'default' | Isolate jobs by namespace |

$3

| Option | Type | Default | Description |
|--------|------|---------|-------------|
| maxAttempts | number | 3 | Maximum retry attempts |
| backoff | string | 'exponential' | 'exponential' / 'linear' / 'fixed' |
| initialDelayMs | number | 1000 | Initial retry delay |
| maxDelayMs | number | 60000 | Maximum retry delay |
| timeoutMs | number | 30000 | Per-attempt timeout |
| jitter | number | 0.1 | Randomization factor (0-1) |

$3

| Method | Description |
|--------|-------------|
| result() | Await job completion and get result |
| status() | Get current status (pending/running/success/dead) |
| details() | Get full job details including attempt history |
| cancel() | Cancel a pending job |

$3

`typescript
reseolio.on('job:start', (job) => console.log(Started: ${job.name}));
reseolio.on('job:success', (job, result) => console.log(Success: ${job.name}));
reseolio.on('job:error', (job, error) => console.log(Error: ${error}));
reseolio.on('job:dead', (job) => console.log(Dead: ${job.name}));
`

---

🏗️ Architecture

`
┌─────────────────────────────────────────────────────────────────┐
│ Your App (Node.js) │
│ ┌───────────────────────────────────────────────────────────┐ │
│ │ reseolio SDK │ │
│ │ - durable() wrapper │ │
│ │ - Worker loop (executes YOUR code) │ │
│ └───────────────────────┬───────────────────────────────────┘ │
│ │ gRPC │
│ ┌───────────────────────▼───────────────────────────────────┐ │
│ │ reseolio-core (Rust binary, ~5MB) │ │
│ │ - Job scheduler │ │
│ │ - Retry logic │ │
│ │ - Crash recovery │ │
│ └───────────────────────┬───────────────────────────────────┘ │
│ │ │
└──────────────────────────│──────────────────────────────────────┘
│
┌────────▼────────┐
│ PostgreSQL │
│ (Your existing │
│ database) │
└─────────────────┘
`

---

💡 Best Practices

$3


`typescript
// ❌ Ambiguous
reseolio.durable('process-data', ...);

// ✅ Crystal clear
reseolio.durable('billing:subscription:charge', ...);
`

$3


`typescript
// ✅ Pass IDs
processOrder({ orderId: '123' });

// ❌ Don't pass large objects
processOrder({ ...hugeUserObject, ...hugeOrderHistory });
`

$3


`typescript
reseolio.durable('...', handler, {
timeoutMs: 5000 // Fail after 5s to prevent zombie jobs
});
`

$3

`typescript
// Use DB constraints
await db.query('INSERT ... ON CONFLICT DO NOTHING');

// Or check state first
if (await isAlreadyProcessed(orderId)) return;
`

---

🆚 Comparison

| Aspect | Message Queues | Temporal | Reseolio |
|--------|----------------|----------|--------------|
| Philosophy | Fire and forget | Complex workflows | Simple durability |
| Infrastructure | Redis/RabbitMQ | 4+ services | Just PostgreSQL |
| Learning Curve | Moderate | Steep | Minimal |
| Result Tracking | Manual | Built-in | Built-in |
| Await Job Result | ❌ | ✅ | ✅ |

---

🔮 Roadmap

- [ ] Visual Dashboard (npx reseolio ui`)
- [ ] Prometheus Metrics
- [ ] Cron Scheduling
- [ ] Python SDK
- [ ] Go SDK

---

🤝 Contributing

We welcome contributions! See CONTRIBUTING.md for guidelines.

---

📄 License

MIT © Reseolio Contributors

---