# Coming from moleculer-cqrs

> Where each part of moleculer-cqrs went.

effect-cqrs keeps the ideas of [moleculer-cqrs](https://github.com/davidnussio/moleculer-cqrs) and changes how they are put together: services and actions become an Effect service, validation becomes `Schema`, and thrown errors become typed ones.

| moleculer-cqrs                           | effect-cqrs                                                |
| ---------------------------------------- | ---------------------------------------------------------- |
| `CQRSEventSourcing({ aggregate })` mixin | `AggregateService.make(aggregate)`                         |
| `call todo.command`                      | `todos.commands.x(id, payload)` or `todos.dispatch(json)`  |
| `call todo.read-model`                   | `todos.state(id, { finishTime })`                          |
| `call todo.history`                      | `todos.history(id, { payload, startTime, finishTime })`    |
| `call todo.replay`                       | `viewModels.replay({ viewModels, startTime, finishTime })` |
| view model service with `events`         | `ViewModel.make({ handlers, dispose })`                    |
| `new CQRSFixture(aggregate)`             | `Fixture.make(aggregate)`                                  |
| `.givenEvents([...])`                    | `.givenEvents([...])`                                      |
| `.when(createNews, payload)`             | `.when("createNews", payload)`                             |
| `.expectEvent(event)`                    | `.expectEvent(event)` or `.expectEvent("Tag")`             |
| `.inspectState(cb)`                      | `.inspectState(cb)`                                        |
| `.whenThrow(command).toThrow(...)`       | `.whenFails(command, payload)`, which returns the error    |
| `fastest-validator`                      | `Schema`                                                   |
| `throw` in a command                     | typed errors                                               |
| `resolve-storage-*` adapters             | `EventStore.Backend`                                       |

## The read side

The largest change is how view models get events. moleculer-cqrs broadcasts them over the broker, so an event sent while a service is down is lost until someone replays. Here view models pull from the store from their own checkpoint, so they can’t miss one, and `replay` is for rebuilding a view model rather than for recovering events.

## What isn’t there

There is no transport like the Moleculer broker: `dispatch` is the entry point to wire into your own HTTP or RPC layer. There is also no `cqrs generate`.