# Architecture Diagrams
Use this page to understand request flow, module boundaries, and feature layering.
## Request Lifecycle
```mermaid
flowchart LR
A[Client Connection] --> B[Accept Loop]
B --> C[Request Parser]
C --> D[Routing and File Resolution]
D --> E[Policy Layer]
E --> F[Response Builder]
F --> G[Socket Write]
```
What you get:
- Clear separation between parsing, policy, and response generation.
- One request path for correctness and observability.
## Core and Feature Modules
```mermaid
flowchart TD
Core[Core Modules<br/>server request response error]
Async[async_server async_runtime]
Perf[perf_server]
Proto[http2_server http3_profile]
Ent[enterprise]
Scale[distributed_rate_limit tenant_isolation runtime_autotune]
Opt[optimized batch streaming observability]
Core --> Async
Core --> Perf
Core --> Proto
Core --> Ent
Core --> Scale
Core --> Opt
```
Interpretation:
- Core modules own baseline behavior.
- Feature-gated modules extend capability without forcing runtime cost when disabled.
## High-Performance Path
```mermaid
flowchart LR
A[Tokio Listener] --> B[Adaptive Inflight Semaphore]
B --> C[Queue Guard]
C --> D[Request Parse]
D --> E{Static File Fast Path}
E -->|Yes| F[sendfile path and precompressed negotiation]
E -->|No| G[Standard response pipeline]
F --> H[Write Response]
G --> H
```
Operational effect:
- Backpressure limits protect latency under load.
- Fast-path serving avoids expensive work for common static requests.
## Enterprise Policy Layer
```mermaid
flowchart TD
Req[Incoming Request] --> Auth[Auth Policy<br/>API key JWT mTLS subject]
Auth --> AZ[Authorization Hook<br/>RBAC ABAC]
AZ --> Audit[Structured Access Audit Event]
Audit --> Obs[Telemetry and Trace Correlation]
```
Design goal:
- Enforce policy at the edge of request handling.
- Produce auditable events with consistent request context.
## Portability and Release Pipeline
```mermaid
flowchart LR
Dev[Local Dev] --> CI[CI Matrix]
CI --> T1[Tier 1 Targets]
CI --> T2[Tier 2 Checks]
T1 --> Artifacts[Release Artifacts]
T2 --> Artifacts
Artifacts --> GH[GitHub Releases]
```
Delivery goal:
- Validate behavior on macOS, Linux, and Windows targets.
- Produce reproducible binaries and container artifacts.