Agent-skills-standard nestjs-notification

Build dual-write notification services with database persistence and FCM push delivery in NestJS. Use when creating notification entities, sending push via FCM, or implementing in-app notification feeds. (triggers: notification.service.ts, notification.entity.ts, notification, push, fcm, alert, reminder)

install

source · Clone the upstream repo

git clone https://github.com/HoangNguyen0403/agent-skills-standard

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/HoangNguyen0403/agent-skills-standard "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/nestjs/nestjs-notification" ~/.claude/skills/hoangnguyen0403-agent-skills-standard-nestjs-notification && rm -rf "$T"

manifest: skills/nestjs/nestjs-notification/SKILL.md

source content

NestJS Notification Architecture

Priority: P0 (Standard)

Implement "Dual-Write" notification system: persist to Database (In-App) and send via FCM (Push).

Workflow: Send Notification

Save to database — Persist notification entity with type enum and metadata.
Check FCM token — Verify recipient valid
```
fcmToken
```
; skip push if missing.
Send push — Call FCM inside
```
try/catch
```
; never let FCM failure block request.
Serialize data — Convert Dates to ISO strings; keep FCM
```
data
```
payload flat (IDs only).

Dual-Write Service Example

See implementation examples

Structure

See implementation examples

Implementation Guidelines

Use Dual-Write: Save to DB first, then attempt FCM. Catch FCM errors so they don't block logic.
Define Granular Types: Use
```
NotificationType
```
Enum (e.g.,
```
APPOINTMENT_REMINDER
```
) for frontend icon/color logic.
Stringify Metadata: Store routing data (IDs) as JSON string in DB, but Map to string-only Key-Values for FCM
```
data
```
.
Handle Tokens: Check for
```
fcmToken
```
existence before sending. Fail gracefully if missing.
Serialize Dates: Convert Dates to ISO strings before sending to FCM.

Anti-Patterns

No Generic Types: Avoid
```
type: string
```
. Always use Enum.
No Blocking FCM: Never
```
await
```
FCM without
```
try/catch
```
. It shouldn't crash request.
No Complex Data in Push: Keep FCM
```
data
```
payload flat and minimal (IDs only). Fetch details on open.