Technical architecture overview

graph TB
subgraph "Frontend Next.js"
FE_APP["layout.tsx"]
FE_PRISMA["lib/prisma.ts"]
FE_API["services/* + app/api"]
end
subgraph "Backend FastAPI"
BE_MAIN["app.main:app"]
BE_STREAM["app.stream.asgi:asgi_app"]
BE_LLM["core/llm.py"]
BE_DEPS["core/deps.py"]
end
subgraph "Infrastructure"
DOCKER_DEV["docker-compose.yaml"]
DOCKER_HOST["frontend/docker-compose.yaml"]
DOCKER_PROD["docker-compose.prod.yaml"]
DB["PostgreSQL"]
K["Kafka"]
end
FE_APP --> FE_API
FE_API --> BE_MAIN
BE_MAIN --> BE_DEPS
BE_DEPS --> BE_LLM
BE_MAIN --> K
K --> BE_STREAM
FE_PRISMA --> DB
BE_MAIN --> DB
BE_STREAM --> DB
DOCKER_DEV --> FE_APP
DOCKER_DEV --> BE_MAIN
DOCKER_DEV --> BE_STREAM
DOCKER_DEV --> DB
DOCKER_DEV --> K
DOCKER_HOST --> DB
DOCKER_HOST --> K
DOCKER_PROD --> FE_APP
DOCKER_PROD --> BE_MAIN
DOCKER_PROD --> DB
DOCKER_PROD --> K

graph TB
Client["Browser"]
NextApp["Next.js"]
BFF["BFF routes"]
FastAPI["API role"]
Worker["Worker role"]
LLMFactory["LLM factory"]
DB["PostgreSQL"]
K["Kafka"]
Client --> NextApp
NextApp --> BFF
BFF --> FastAPI
FastAPI --> K
K --> Worker
Worker --> LLMFactory
FastAPI --> DB
Worker --> DB

sequenceDiagram
participant UI as "Next.js UI"
participant BFF as "BFF"
participant Backend as "FastAPI"
participant DB as "PostgreSQL"
UI->>BFF : Feature request
BFF->>Backend : Bearer + LLM headers
Backend->>DB : job row
Backend-->>BFF : 202 job_id
BFF-->>UI : waiter

sequenceDiagram
participant Client as "BFF"
participant Backend as "API"
participant LLM as "resolve_for_job"
participant K as "Kafka"
Client->>Backend : POST /api/v1/ats/evaluate
Backend->>LLM : pin provider/model/encrypted key
Backend->>K : publish envelope
Backend-->>Client : 202

flowchart TD
Start(["LLM Invocation"]) --> CheckProvider["Select provider and model"]
CheckProvider --> CreateLLM["create_llm(...)"]
CreateLLM --> Invoke["ainvoke()"]
Invoke --> Parse["parse JSON"]
Parse --> Return["Structured result"]

graph TB
Prisma["Prisma frontend/lib/prisma.ts"]
DB["PostgreSQL"]
API["API role"]
W["Worker"]
K["Kafka"]
Jobs["talentsync_backend.job"]
Prisma --> DB
API --> DB
API --> K
K --> W
W --> Jobs
Jobs --> DB