TamboUI talks to the terminal through a pluggable Backend. Backends are discovered via ServiceLoader, so adding one is just a dependency:

Module Description Requires

tamboui-jline3-backend

JLine 3 based backend; the reliable default on all platforms

Java 8+

tamboui-panama-backend

Panama (FFM) backend with no third-party dependencies

Java 22+

tamboui-aesh-backend

Aesh based backend, e.g. for SSH/browser-hosted terminals

Java 8+

An application can ship several backends at once. tamboui-panama-backend is safe to include in applications that also run on older JVMs: on a runtime older than Java 22 its provider is skipped during discovery.

Selecting a backend

By default, BackendFactory.create() auto-discovers providers on the classpath and uses the first one that successfully creates a backend. To control the choice, set the tamboui.backend system property or the TAMBOUI_BACKEND environment variable:

# by simple name
java -Dtamboui.backend=jline3 ...

# by fully qualified provider class name
java -Dtamboui.backend=dev.tamboui.backend.jline3.JLineBackendProvider ...

# preference order with fallback: try panama, fall back to jline3
# (e.g. when the same application runs on both Java 21 and Java 22+)
java -Dtamboui.backend=panama,jline3 ...

A comma-separated list is a preference order: entries that are not usable on the current JVM are skipped, and the first usable provider wins. An error is raised only when none of the listed providers can be used.

Embedders that manage their own classloaders (plugin systems, app servers) can pin discovery to a specific loader via TuiConfig:

TuiConfig config = TuiConfig.builder()
    .backendClassLoader(pluginClassLoader)
    .build();

Troubleshooting

Run the diagnostic entry point of tamboui-core with your application’s classpath to see what is discovered on the current JVM, including providers that failed to load:

jbang dev.tamboui:tamboui-core:{revnumber}
# or: java -cp <your-classpath> dev.tamboui.Main
java.version: 21.0.9
tamboui.backend: <unset>
backend.provider_count: 1
backend.provider_names: jline3
backend.provider_error.0: dev/tamboui/backend/panama/PanamaBackendProvider has been compiled
  by a more recent version of the Java Runtime (class file version 66.0), ...

Selection errors distinguish three situations:

The requested provider exists but cannot load on this JVM — the real cause is reported, with a hint to add a fallback:

BackendProvider(s) matching 'panama' were found on the classpath but could not be initialized (see cause).
Failures:
  dev/tamboui/backend/panama/PanamaBackendProvider has been compiled by a more recent version ...
Available providers: jline3 (dev.tamboui.backend.jline3.JLineBackendProvider)
Use a compatible Java runtime, or append a working fallback to the list, e.g. -Dtamboui.backend=panama,jline3

The requested name matches nothing — usable providers are listed, and providers that were found but dropped are disclosed so a typo of a present-but-incompatible backend is not mistaken for a missing dependency:

No BackendProvider found on classpath for any of the specified providers: 'bogus'.
Available providers: jline3 (dev.tamboui.backend.jline3.JLineBackendProvider)
Note: 1 additional provider(s) were found but could not be loaded on this JVM:
  dev/tamboui/backend/panama/PanamaBackendProvider has been compiled by a more recent version ...
Add a backend dependency such as tamboui-jline3-backend or tamboui-panama-backend.

No provider loads at all — each failure is reported with its cause (the first as the exception cause, the rest as suppressed exceptions).