ledgerhq DevTools import boundaries
Every @devtools/* package is self-contained. The only permitted cross-package imports within the devtools scope are listed in the table below; all others are forbidden.
Rules
| Package | May import from @devtools/* |
|---|---|
@devtools/registry |
any @devtools/<tool> |
@devtools/shell |
@devtools/transport, @devtools/registry |
@devtools/bindings |
@devtools/registry only |
@devtools/wire |
@devtools/transport, @devtools/protocols |
@devtools/protocols |
@devtools/transport only |
@devtools/relay |
@devtools/transport only |
@devtools/transport-panel |
@devtools/transport only |
@devtools/<tool> |
none |
All other @devtools/* → @devtools/* imports are forbidden.
Why
The devtools architecture decouples tools from the shell through the registry. The shell lazy-loads tools via metadata.loader; tools never know the shell exists. If a tool imports the shell or another tool directly:
- The lazy-load boundary collapses — the tool is bundled eagerly.
- A circular dependency becomes likely (tool → shell → registry → tool).
- The tool can no longer be rendered standalone, outside the shell.
If bindings or shell import a tool package directly (instead of through the registry):
- The registry's discriminated union is bypassed and TypeScript loses the narrowing guarantee on
DevToolsConfig. - The
import()split point disappears, defeating code-splitting.
Consequences of a violation
- Tool imports shell or registry: The tool becomes coupled to shell internals; standalone rendering and unit-testing break.
- Tool imports another tool: Cross-tool coupling; removing or renaming one tool requires editing the other.
- Shell or bindings import a tool directly: Eager bundle; code-split lost; registry union integrity broken.
Correct pattern
Cross-cutting concerns (shared types, utilities) must not live in a tool package. Extract them to a standalone library with no @devtools/* scope, then import that from whichever packages need it.
App state and wiring for a tool arrive as props, built in @devtools/bindings — the single sanctioned bridge to Ledger Live internals. A tool that needs more data from the app gets new props, not a new import.
Documentation
When adding a new package under devtools/, its README.md must state:
- Which
@devtools/*packages it may import, per the table above. - That all other
@devtools/*imports are forbidden, with a pointer to this rule.