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Flagsmith Client

The SDK client for Rust Flagsmith allows you to manage feature flags and remote config across multiple projects, environments and organisations.

The source code for the client is available on Github.


Retrieving feature flags for your project

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In your application initialise the BulletTrain client with your API key

let bt = bullettrain::Client::new("<Your API Key>");

To check if a feature flag exists and is enabled:

let bt = bullettrain::Client::new("<Your API Key>");
if bt.feature_enabled("cart_abundant_notification_ab_test_enabled")? {
    println!("Feature enabled");

To get the configuration value for feature flag value:

use bullettrain::{Client,Value};

let bt = Client::new("<Your API Key>");

if let Some(Value::String(s)) = bt.get_value("cart_abundant_notification_ab_test")? {
    println!("{}", s);

More examples can be found in the Tests

Override default configuration

By default, client is using default configuration. You can override configuration as follows:

let bt = bullettrain::Client {
    api_key: String::from("secret key"),
    base_uri: String::from(""),


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