**What**
This PR introduces experimental Hot Module Replacement (HMR) for the Medusa backend, enabling developers to see code changes reflected immediately without restarting the server. This significantly improves the development experience by reducing iteration time.
### Key Features
- Hot reload support for:
- API Routes
- Workflows & Steps
- Scheduled Jobs
- Event Subscribers
- Modules
- IPC-based architecture: The dev server runs in a child process, communicating with the parent watcher via IPC. When HMR fails, the child process is killed and restarted, ensuring
clean resource cleanup.
- Recovery mechanism: Automatically recovers from broken module states without manual intervention.
- Graceful fallback: When HMR cannot handle a change (e.g., medusa-config.ts, .env), the server restarts completely.
### Architecture
```mermaid
flowchart TB
subgraph Parent["develop.ts (File Watcher)"]
W[Watch Files]
end
subgraph Child["start.ts (HTTP Server)"]
R[reloadResources]
R --> MR[ModuleReloader]
R --> WR[WorkflowReloader]
R --> RR[RouteReloader]
R --> SR[SubscriberReloader]
R --> JR[JobReloader]
end
W -->|"hmr-reload"| R
R -->|"hmr-result"| W
```
### How to enable it
Backend HMR is behind a feature flag. Enable it by setting:
```ts
// medusa-config.ts
module.exports = defineConfig({
featureFlags: {
backend_hmr: true
}
})
```
or
```bash
export MEDUSA_FF_BACKEND_HMR=true
```
or
```
// .env
MEDUSA_FF_BACKEND_HMR=true
```
Co-authored-by: Oli Juhl <59018053+olivermrbl@users.noreply.github.com>
Co-authored-by: Carlos R. L. Rodrigues <37986729+carlos-r-l-rodrigues@users.noreply.github.com>
RESOLVES CORE-1153
**What**
- This pr mainly lay the foundation the caching layer. It comes with a modules (built in memory cache) and a redis provider.
- Apply caching to few touch point to test
Co-authored-by: Carlos R. L. Rodrigues <37986729+carlos-r-l-rodrigues@users.noreply.github.com>
PARTIALLY RESOLVES FRMW-2876
**What**
Fix wrong usage of the `subscriberId` in the event bus. It happens that the subscriber id coming from the context was not used at all. This issue lead to duplicated event subscriber with the same subscriber id, it also prevent unsubscribing from event since rand id will be assigned.
**NOTE**
This PR does not handle overide strategy for subscribers with the same id. this still needs to be discussed
What:
When `autocapture` is enabled, the webhook is processed before the order was created.
The payment processing workflows were merged into a single one
FIXES: SUP-118, SUP-9
https://github.com/medusajs/medusa/issues/9998
* chore: Treat internal event differently, primarely do not display info log for those events
* revert doc
* add few tests
* only set internal option if present
* revert to previous condition
* start including feedback after discussion
* include feedback
* fix modules integration tests
* fix modules integration tests
* fix event bus local
* chore: ability to group events on redis event bus
* chore: fix tests
* Update packages/modules/event-bus-redis/src/services/event-bus-redis.ts
Co-authored-by: Adrien de Peretti <adrien.deperetti@gmail.com>
* chore: change shape of input and body data
* chore: fix builds
* chore: address comments
* chore: fix unit test
---------
Co-authored-by: Adrien de Peretti <adrien.deperetti@gmail.com>
