Skip to main content
Erst CLI offers flexible configuration through multiple methods, with a clear precedence order to give you control at every level.

​
Configuration hierarchy

Configuration values are loaded in the following order, with later sources overriding earlier ones:
  1. Default values - Built-in sensible defaults
  2. Configuration files - TOML files on disk
  3. Environment variables - System environment settings
  4. Command-line flags - Direct CLI arguments
Command-line flags always take precedence over all other configuration methods.

​
Configuration files

Erst searches for TOML configuration files in these locations (in order):
  1. .erst.toml in the current directory
  2. ~/.erst.toml in your home directory
  3. /etc/erst/config.toml system-wide configuration

​
Example configuration file

Copy erst.example.toml to one of the locations above:
~/.erst.toml
# RPC URL for the Stellar network (single URL)
rpc_url = "https://soroban-testnet.stellar.org"

# Multi-RPC URLs for automatic fallback (array syntax)
# rpc_urls = ["https://rpc1.stellar.org", "https://rpc2.stellar.org"]

# Network: public, testnet, futurenet, or standalone
network = "testnet"

# Path to the ERST simulator (optional)
# simulator_path = "/path/to/simulator"

# Log level: trace, debug, info, warn, error
log_level = "info"

# Cache directory for storing traces and snapshots
# cache_path = "~/.erst/cache"

# Request timeout in seconds (1-300)
# request_timeout = 15

# Opt-in anonymous crash reporting
# crash_reporting = false

​
Core configuration options

​
Network connection

​
rpc_url
string
default:"https://soroban-testnet.stellar.org"
Single RPC endpoint URL for connecting to the Stellar network.
​
rpc_urls
array
Array of RPC URLs for automatic fallback. Use this for high availability setups.
rpc_urls = ["https://rpc1.stellar.org", "https://rpc2.stellar.org"]
​
network
string
default:"testnet"
Network identifier. Valid values:
​
network_passphrase
string
Custom network passphrase for private networks. Required when using custom networks.Standard passphrases:
  • Mainnet: Public Global Stellar Network ; September 2015
  • Testnet: Test SDF Network ; September 2015

​
Simulator settings

​
simulator_path
string
Custom path to the erst-sim binary. If not set, Erst searches:
  1. Current directory (./erst-sim)
  2. Development path (./simulator/target/release/erst-sim)
  3. System PATH

​
Logging and debugging

​
log_level
string
default:"info"
Unified log level for both Go CLI and Rust simulator.Valid values: trace, debug, info, warn, error

​
Storage and caching

​
cache_path
string
default:"~/.erst/cache"
Directory for storing transaction traces and snapshots.

​
Request settings

​
request_timeout
number
default:"15"
HTTP request timeout in seconds. Must be between 1 and 300.
​
rpc_token
string
Authentication token for RPC endpoints that require authorization.

​
Crash reporting

​
crash_reporting
boolean
default:"false"
Enable anonymous crash reporting to help improve Erst.When enabled, fatal panics send minimal reports (error message, stack trace, OS/arch, version) to maintainers.
No transaction data or personal information is ever included.
​
crash_endpoint
string
default:"https://crash.erst.dev/v1/report"
Custom endpoint for crash reports. Only used when crash_reporting is enabled and no Sentry DSN is set.
​
crash_sentry_dsn
string
Sentry DSN for crash reporting. Obtain from your Sentry project settings.
crash_sentry_dsn = "https://<key>@<org>.ingest.sentry.io/<project>"

​
Configuration validation

Erst validates your configuration on startup and provides clear error messages:

​
Required fields

  • rpc_url cannot be empty (unless using a named network)

​
Network validation

  • network must be one of: public, testnet, futurenet, standalone

​
Request timeout validation

  • request_timeout must be between 1 and 300 seconds

​
Default values

When no configuration is provided, Erst uses these defaults: 
{
  "rpc_url": "https://soroban-testnet.stellar.org",
  "network": "testnet",
  "log_level": "info",
  "cache_path": "~/.erst/cache",
  "request_timeout": 15,
  "crash_reporting": false
}

​
Advanced configurations

​
Multi-RPC fallback

For production environments, configure multiple RPC endpoints: 
rpc_urls = [
  "https://primary.stellar.org",
  "https://backup.stellar.org",
  "https://fallback.stellar.org"
]
network = "public"

​
Development setup

rpc_url = "http://localhost:8000/soroban/rpc"
network = "standalone"
log_level = "debug"
simulator_path = "./simulator/target/debug/erst-sim"

​
Production security

rpc_url = "https://soroban.stellar.org"
rpc_token = "your-api-token"
network = "public"
log_level = "warn"
crash_reporting = true
crash_sentry_dsn = "https://key@org.ingest.sentry.io/project"

​
Configuration storage

Erst stores additional configuration data in:
  • ~/.erst/config.json - General configuration (JSON format)
  • ~/.erst/networks.json - Custom network profiles
  • ~/.erst/cache/ - Transaction traces and snapshots
All configuration files use restricted permissions (0600) and directories use 0700 for security.

​
Viewing current configuration

Use the erst config command to view your current configuration: 
erst config show

​
Next steps

Environment variables

Configure Erst using environment variables

Custom networks

Set up private and local Stellar networks