# App Security

How Simpl Desktop protects your database connections and data.

## Overview

As a native desktop application, Simpl takes a fundamentally different approach to security: your credentials never leave your machine. There are no servers storing your connection strings, and your database queries go directly from your computer to your database.

## The Desktop Advantage

### Your Credentials Stay Local

Unlike web-based database tools, Simpl Desktop stores everything locally:

| Aspect | How It Works |
| --- | --- |
| Connection strings | Stored only on your device |
| Encryption | OS secure storage (safeStorage) when available |
| Database queries | Direct connection from your computer |
| Our servers | Never see your credentials or data |

This means:

- **No server-side storage** \- We can't leak what we don't have
- **No network hops** \- Your queries go directly to your database
- **Full control** \- Your data stays under your control

## Local Encryption

### How Credentials Are Protected

Even on your local machine, your connection strings are encrypted using your operating system's secure credential storage.

When available, Simpl uses Electron's **safeStorage** API, which leverages your OS-level encryption:

| Platform | Storage Method |
| --- | --- |
| macOS | Keychain |
| Windows | DPAPI (Data Protection API) |
| Linux | Secret Service API (e.g., gnome-keyring) |

If safeStorage is unavailable on your system, Simpl falls back to file-based AES-256-GCM encryption with a locally-stored key.

| Aspect | Implementation |
| --- | --- |
| Primary | OS secure storage (safeStorage) |
| Fallback | AES-256-GCM with unique IV per connection |
| Key Size | 256 bits |

Your credentials are:

- **Encrypted** before being stored on disk
- **Decrypted** only when establishing connections
- **Never transmitted** to any external servers

## Query Security

### SQL Injection Prevention

Simpl uses multiple layers to prevent SQL injection:

1. **Identifier allow-listing** \- Table and column names are validated against the introspected schema
2. **PostgreSQL identifier quoting** \- All identifiers use proper quoting (`"schema"."table"`)
3. **Parameterized queries** \- All user values are passed as parameters, never concatenated

### Example

When you filter for `name = "John"`:

```sql
-- What Simpl executes (safe)
SELECT * FROM "users" WHERE "name" = $1
-- Parameters: ['John']

-- NOT this (unsafe)
SELECT * FROM users WHERE name = 'John'
```

### Query Timeouts

All queries have a 10-second timeout to prevent:

- Runaway queries from affecting database performance
- Connection pool exhaustion
- Hanging connections

## Direct Database Connections

### No Middlemen

When you connect to a database with Simpl:

1. Your computer connects directly to your database server
2. No proxy servers or intermediaries
3. No data passes through our infrastructure
4. Connection uses your database's native security (SSL/TLS)

### Network Security

For maximum security, configure your database connection with:

1. **SSL/TLS connections** \- Add `?sslmode=require` to your connection string
2. **IP allowlisting** \- Restrict database access to known IPs
3. **VPN/Private networks** \- Use private database endpoints when available

### SSL Connection Example

```
postgresql://user:pass@host:5432/db?sslmode=require
```

SSL modes:

| Mode | Description |
| --- | --- |
| `require` | Encrypt connection, don't verify certificate |
| `verify-ca` | Verify server certificate is signed by trusted CA |
| `verify-full` | Verify certificate and hostname |

## Access Control

### Database Credentials

Simpl connects using the credentials you provide. Access is limited by:

- Your database user's privileges
- PostgreSQL's built-in access control
- Your database's network policies

### Recommendation

Create a dedicated database user for Simpl with appropriate permissions:

```sql
-- Example: Read-only access
CREATE USER simpl_readonly WITH PASSWORD 'secure_password';
GRANT CONNECT ON DATABASE mydb TO simpl_readonly;
GRANT USAGE ON SCHEMA public TO simpl_readonly;
GRANT SELECT ON ALL TABLES IN SCHEMA public TO simpl_readonly;
```

For editing capability:

```sql
-- Example: Read-write access
CREATE USER simpl_readwrite WITH PASSWORD 'secure_password';
GRANT CONNECT ON DATABASE mydb TO simpl_readwrite;
GRANT USAGE ON SCHEMA public TO simpl_readwrite;
GRANT SELECT, INSERT, UPDATE, DELETE ON ALL TABLES IN SCHEMA public TO simpl_readwrite;
```

## What We Store

### On Your Machine

| Data | Purpose | Protection |
| --- | --- | --- |
| Connection strings | Database access | OS secure storage (safeStorage) |
| Schema cache | Performance | Local storage |
| Layout configs | User preferences | Local storage |

### On Our Servers

| Data | Purpose |
| --- | --- |
| License key | Verify your purchase |
| Email address | Account management |

We do **NOT** store:

- Your database credentials
- Your database data
- Your query history
- Any information about your database contents

## Best Practices

### For Connection Credentials

1. **Use dedicated users** \- Don't use superuser/admin accounts
2. **Limit privileges** \- Grant only necessary permissions
3. **Rotate passwords** \- Update credentials periodically
4. **Use SSL** \- Enable encrypted connections

### For Database Configuration

1. **Enable SSL** \- Require encrypted connections
2. **Allowlist IPs** \- Restrict network access
3. **Audit logging** \- Enable PostgreSQL logging
4. **Regular backups** \- Maintain backup strategy

## Privacy

### Data Privacy

Simpl Desktop is designed with privacy at its core:

- We never access your database data
- We can't see your connection information
- We don't analyze or mine your database contents
- Your queries are executed locally, not through our servers

## Questions

For security-related questions:

- Email: [hello@simpl.sh](mailto:hello@simpl.sh)

## Next Steps

- Return to the [documentation hub](/content/docs/index.html)
- [Set up your first connection](/content/docs/getting-started/connecting/index.html)
- [Contact support](mailto:hello@simpl.sh) for help