Architecture

xe/
├── cmd/
│   └── xe/         Single binary — node daemon, wallet, send/receive, leases, ssh, chat
├── core/           Domain logic — ledger, crypto, encoding, PoW, voting, quorum, supply
├── store/          Pluggable storage — MemStore (testing), BadgerStore (production)
├── net/            libp2p networking — gossip, sync, DHT discovery, netcheck, messaging, tunnel
├── node/           Orchestration — ties all packages together into a running node
├── api/            HTTP REST + SSE API — handler, routes, CORS, rate limits, /health /ready
├── statechain/     Deterministic state machine — DAO governance, KV store, activations, sync
├── vm/             VM abstraction — Lima and QEMU managers, mock, credentials
├── perf/           Performance certificates — PoW-chain + memory benchmark, price multiplier
├── web/            Embedded web UI — HTML + ES modules + CSS, served by xe node --ui
├── client/         HTTP client shared by CLI subcommands
├── directory/      P2P account directory — registration, verification, gossip
├── chat/           P2P messaging — envelope format, PoW, chat store
├── logging/        Levelled, optionally JSON, size-rotated logs
├── metrics/        Prometheus registry for the operator listener
├── genesis/        Published genesis bundles, one directory per network
├── deploy/         systemd unit, pm2 ecosystem, Dockerfile, monitoring stack
└── scripts/ci/     Build and release helpers

AddBlock(b *Block)
  │
  ├── 1. Normalize hex fields (lowercase)
  ├── 2. VerifyBlock — recompute hash + check ed25519 signature
  ├── 3. ValidatePoW — blake2b(nonce || hash) >= difficulty
  ├── 4. Timestamp check — within ±1 hour of local time
  ├── 5. Duplicate check — block hash not already in store
  ├── 6. Conflict detection — check if Previous hash is shared
  │     ├── No conflict → continue on main chain
  │     └── Conflict → stage block, fire callback, return
  │
  ├── 6b. Opening-key check — previous == "0" requires pub_key deriving the account; any later block must omit it
  │
  ├── 7. Type-specific validation (per-account lock held)
  │     ├── send     → balance sufficient, frontier matches, amount > 0
  │     ├── receive  → pending send exists, destination matches
  │     ├── mint     → XUSD only, account in sys.minter, no source/destination/memo, amount > 0
  │     ├── burn     → XE only, no source/destination, amount > 0, balance sufficient
  │     ├── lease    → XUSD only, cost formula correct against the provider certificate, balance sufficient
  │     ├── lease_accept → lease exists, valid certificate, emission params locked, attestations valid (no stake)
  │     ├── lease_renew  → consumer only, lease accepted, attested before effective expiry, cost at current certificate
  │     ├── lease_settle → lease expired within settle grace, XE emission formula summed over segments
  │     ├── lease_cancel → consumer only, source lease exists and is cancellable
  │     ├── lease_force_settle → consumer only, after grace + gap, before escrow expiry
  │     └── multisig_open/update → keyset valid; open derives the account address, update rotates the keyset
  │
  ├── 8. Update in-memory state (asset balances, delegation weights)
  └── 9. Write to store (atomic commit via AtomicBlockStore)