Build a full backoffice in 10 minutes

This is the fastest way to understand what Mateu is really for.

In a few minutes, you can go from a Spring Boot project to a working backoffice with:

forms
validation
actions
navigation
relationships
browser feedback

And you do it all in Java.

What you’ll build

A small admin app with:

a home screen
a menu
a CRUD screen
validation
a foreign key relationship
a success notification

No frontend project. No REST controllers for each screen. No duplicated models.

Step 1 — Create the UI root

Start with a screen:

@UI("/admin")
@Title("Admin")
public class AdminHome {

  @Menu
  AdminMenu admin;

}

public class AdminMenu {

  @Menu
  RolesCrud roles;

}

This already gives you:

a UI root
a navigation entry
a place to expose your backoffice modules

Step 2 — Create a real form

Now define the form for one entity.

public class RoleViewModel implements Identifiable, CrudEditorForm<String>, CrudCreationForm<String> {

  @EditableOnlyWhenCreating
  @NotEmpty
  String id;

  @NotEmpty
  String name;

  @Colspan(2)
  @Style("width: 100%;")
  String description;

  @Lookup(search = PermissionIdOptionsSupplier.class, label = PermissionIdLabelSupplier.class)
  @Colspan(2)
  @Style("width: 100%;")
  @Stereotype(FieldStereotype.checkbox)
  List<String> permissions;

  @Override
  public String id() {
    return id;
  }

  @Override
  public String create(HttpRequest httpRequest) {
    return id;
  }

  @Override
  public void save(HttpRequest httpRequest) {
  }
}

In one class, you just defined:

state
validation
layout hints
rendering intent
a relationship
create/save lifecycle

Step 3 — Connect it to your application layer

Now wire the form to your actual use cases.

public class RoleViewModel implements Identifiable, CrudEditorForm<String>, CrudCreationForm<String> {

  @EditableOnlyWhenCreating
  @NotEmpty
  String id;

  @NotEmpty
  String name;

  @Colspan(2)
  @Style("width: 100%;")
  String description;

  @Lookup(search = PermissionIdOptionsSupplier.class, label = PermissionIdLabelSupplier.class)
  @Colspan(2)
  @Style("width: 100%;")
  @Stereotype(FieldStereotype.checkbox)
  List<String> permissions;

  final CreateRoleUseCase createRoleUseCase;
  final SaveRoleUseCase saveRoleUseCase;

  public RoleViewModel(CreateRoleUseCase createRoleUseCase, SaveRoleUseCase saveRoleUseCase) {
    this.createRoleUseCase = createRoleUseCase;
    this.saveRoleUseCase = saveRoleUseCase;
  }

  @Override
  public String create(HttpRequest httpRequest) {
    createRoleUseCase.handle(new CreateRoleCommand(id, name, description, permissions));
    return id;
  }

  @Override
  public void save(HttpRequest httpRequest) {
    saveRoleUseCase.handle(new SaveRoleCommand(id, name, description, permissions));
  }

  @Override
  public String id() {
    return id;
  }
}

Mateu does not replace your application architecture.

It sits on top of it.

Step 4 — Add the CRUD adapter

The adapter connects Mateu’s CRUD lifecycle to your query services and use cases.

public class RoleCrudAdapter implements CrudAdapter<
        RoleViewModel,
        RoleViewModel,
        RoleViewModel,
        NoFilters,
        RoleRow,
        String> {

  final RoleViewModel viewModel;
  final RoleQueryService queryService;
  final DeleteRoleUseCase deleteRoleUseCase;

  public RoleCrudAdapter(
      RoleViewModel viewModel,
      RoleQueryService queryService,
      DeleteRoleUseCase deleteRoleUseCase) {
    this.viewModel = viewModel;
    this.queryService = queryService;
    this.deleteRoleUseCase = deleteRoleUseCase;
  }

  @Override
  public ListingData<RoleRow> search(String searchText, NoFilters filters, Pageable pageable) {
    return queryService.findAll(searchText, filters, pageable);
  }

  @Override
  public void deleteAllById(List<String> selectedIds) {
    deleteRoleUseCase.handle(new DeleteRoleCommand(selectedIds));
  }

  @Override
  public RoleViewModel getView(String id) {
    return viewModel.load(queryService.getById(id).orElseThrow());
  }

  @Override
  public RoleViewModel getEditor(String id) {
    return viewModel.load(queryService.getById(id).orElseThrow());
  }

  @Override
  public RoleViewModel getCreationForm(HttpRequest httpRequest) {
    return viewModel;
  }
}

Step 5 — Expose the CRUD

Now expose it through a Crud.

@Title("Roles")
public class RolesCrud extends Crud<
        RoleViewModel,
        RoleViewModel,
        RoleViewModel,
        NoFilters,
        RoleRow,
        String> {

  final RoleCrudAdapter adapter;

  public RolesCrud(RoleCrudAdapter adapter) {
    this.adapter = adapter;
  }

  @Override
  public CrudAdapter<RoleViewModel, RoleViewModel, RoleViewModel, NoFilters, RoleRow, String> adapter() {
    return adapter;
  }

  @Override
  public String toId(String s) {
    return s;
  }
}

Now you have a real CRUD screen in your backoffice.

Step 6 — Resolve relationships dynamically

Mateu can resolve foreign keys dynamically through backend suppliers.

Options supplier

public class PermissionIdOptionsSupplier implements LookupOptionsSupplier {

  final PermissionQueryService queryService;

  public PermissionIdOptionsSupplier(PermissionQueryService queryService) {
    this.queryService = queryService;
  }

  @Override
  public ListingData<Option> search(String searchText, Pageable pageable, HttpRequest httpRequest) {
    var found = queryService.findAll(searchText, null, pageable);
    return new ListingData<>(new Page<>(
        searchText,
        found.page().pageSize(),
        found.page().pageNumber(),
        found.page().totalElements(),
        found.page().content().stream()
            .map(permission -> new Option(permission.id(), permission.name()))
            .toList()
    ));
  }
}

Label supplier

public class PermissionIdLabelSupplier implements LabelSupplier {

  final PermissionQueryService queryService;

  public PermissionIdLabelSupplier(PermissionQueryService queryService) {
    this.queryService = queryService;
  }

  @Override
  public String label(Object id, HttpRequest httpRequest) {
    return queryService.getLabel((String) id);
  }
}

So your form can work with real relationships without moving logic into the frontend.

Step 7 — Return user feedback directly

You can return browser feedback straight from backend methods.

@Button
public Message notifySave() {
  return new Message("Role saved successfully");
}

Mateu turns that into a browser notification.

No frontend toast code required.

What you just built

With a small amount of Java, you defined:

navigation
CRUD lifecycle
validation
relationships
rendering behavior
user feedback

Mateu handled:

rendering
browser validation
interaction
state binding
UI updates

Why this matters

In a traditional stack, this usually means:

backend model
frontend model
API glue
duplicated validation
duplicated relationships
duplicated navigation

With Mateu, it stays in one place.

Where to go next

If you want the step-by-step version, continue with:

One sentence summary

This is what Mateu is for: building real backoffice applications with minimal code and without a frontend layer.