Architecture Overview

High-level architecture for the Build a Bear Vault, including the on-chain vault, off-chain solver, and protocol execution path.

Architecture Overview

The system is split into two layers:

• on-chain enforcement
• off-chain intelligence and execution

This separation is intentional. The optimizer is computationally heavy, while the vault contract should stay deterministic, auditable, and relatively small.

End-to-end shape

1. Users deposit USDC into the vault
2. The solver computes target allocations off-chain
3. Ranger builds protocol-specific transaction bundles
4. The program stores the approved rebalance proof
5. Protocol transactions are executed
6. The program records the execution proof and updates allocation state

Why this split exists

On-chain should enforce

The program is responsible for:

• vault state
• shares and treasury accounting
• policy boundaries
• strategy registry
• withdrawal lifecycle
• rebalance proof storage

Off-chain should decide

The off-chain stack is responsible for:

• data gathering
• scoring strategies
• computing target weights
• building protocol instructions
• bundling transactions
• orchestrating retries and operator workflows

Design principles

Policy before optimization

No strategy can be selected beyond the configured policy envelopes.

Deterministic before adaptive

The first version uses deterministic math and explicit haircuts, not ML or opaque heuristics.

Proofs on-chain, heavy compute off-chain

Only the approved plan and execution proof are committed on-chain.

Main modules

Module	Role
programs/multi_strategy_vault/	On-chain program and account model
services/adapters/	Protocol-specific execution builders
services/solver/	Strategy scoring and rebalance plan generation
services/ranger/	Execution runtime, vault clients, operator CLIs
services/shared/	Shared types, configs, hashes, math, env loading

Read next

• On-chain Architecture
• Off-chain Architecture
• Solver Deep Dive
• Rebalance Flow