Stateless API Surface vs Stateful Execution Core

WAproxy exposes a minimal HTTP API surface,
but internally operates as a strictly stateful execution engine.

This separation is intentional.

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STATELESS API LAYER
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Each HTTP request is independent.

Endpoints such as:

/v1/<coin>?mode=wallet_send
/v1/<coin>?mode=wallet_balance
/v1/<coin>?mode=wallet_receive

do not rely on client session state.

Authentication is key-based.
Idempotency is request-scoped.

No session memory exists at API layer.

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STATEFUL EXECUTION CORE
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Internally, WAproxy maintains:

- wallet balance state
- idempotency records
- transaction history
- confirmation tracking
- atomic execution logs

Execution correctness depends on persistent state.

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WHY THIS DISTINCTION MATTERS
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Stateless API layer provides:

- horizontal scalability
- load balancer compatibility
- retry-friendly behavior
- simple integration model

Stateful core provides:

- deterministic execution
- economic integrity
- atomic balance mutation
- replay protection

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DESIGN RULE
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The API must remain simple.
The core must remain consistent.

Stateless input.
Stateful correctness.

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FAILURE HANDLING IMPLICATION
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If API layer restarts:

- Idempotency must remain valid.
- Balance state must remain correct.
- Broadcast history must persist.

State must never depend on memory-only cache.

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ARCHITECTURAL STATEMENT
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WAproxy is stateless at the interface,
but stateful at the execution core.

Deterministic transport requires persistent state discipline.