{
  "chain_slug": "base",
  "name": "Base",
  "scorecard_profile": "rollup-L2",
  "evaluated_at": "2026-04-18",
  "evaluator": "layerqu-v2-scoring-agent-1",
  "v1_reference": "chainscreen-v1-archive",
  "dimensions": {
    "1_cryptographic_exposure": {
      "weight": 0.12,
      "score": 28,
      "sub_scores": {
        "1a_primitive_inventory": {
          "score": 10,
          "primitives_named": [
            "ECDSA secp256k1 (inherited Ethereum)",
            "Keccak-256",
            "BLS12-381 (Ethereum L1 settlement)"
          ],
          "evidence": [
            "https://docs.base.org"
          ],
          "note": "OP Stack inheritance from Optimism. Ethereum primitives."
        },
        "1b_shor_grover_pq_tag": {
          "score": 12,
          "tags": {
            "ECDSA secp256k1": "Shor-break",
            "Keccak-256": "Grover-weaken-128bit",
            "BLS12-381": "Shor-break"
          },
          "evidence": [
            "https://docs.base.org"
          ]
        },
        "1c_algorithm_family_diversity": {
          "score": 0,
          "families_represented": 0,
          "families": [],
          "note": "No PQC families"
        },
        "1d_nist_security_category": {
          "score": 0,
          "mappings": {},
          "note": "No NIST PQC"
        },
        "1e_implementation_quality": {
          "score": 6,
          "formal_verification": "OP Stack audited by Sigma Prime, Trail of Bits",
          "constant_time": "standard",
          "libraries": [
            "libsecp256k1",
            "op-geth fork"
          ],
          "evidence": [
            "https://github.com/ethereum-optimism/optimism"
          ]
        }
      },
      "total_artifacts": 2
    },
    "2_hndl_exposure": {
      "weight": 0.08,
      "score": 20,
      "sub_scores": {
        "2a_active_key_exposure": {
          "score": 5,
          "note": "Coinbase-operated sequencer; large retail userbase (millions of wallets). EOA pubkeys exposed."
        },
        "2b_cold_key_exposure": {
          "score": 5,
          "note": "Mainnet since Aug 2023; young chain."
        },
        "2c_signature_longterm_validity": {
          "score": 5,
          "note": "ECDSA sigs + state commitments Shor-breakable."
        },
        "2d_encryption_confidentiality": {
          "score": 5,
          "note": "Standard TLS via Coinbase infra."
        }
      },
      "total_artifacts": 1
    },
    "3_metadata_privacy_exposure": {
      "weight": 0.08,
      "score": 12,
      "sub_scores": {
        "3a_tx_graph_visibility": {
          "score": 3,
          "note": "Pseudonymous EVM transparent ledger."
        },
        "3b_rpc_mempool_concentration": {
          "score": 3,
          "note": "Coinbase-operated single sequencer. High concentration."
        },
        "3c_cross_chain_bridge_correlation": {
          "score": 3,
          "note": "Native Base Bridge visible on L1."
        },
        "3d_retroactive_deanon_risk": {
          "score": 3,
          "note": "No shielded pool."
        }
      },
      "total_artifacts": 1
    },
    "4_migration_architecture": {
      "weight": 0.15,
      "score": 48,
      "sub_scores": {
        "4a_crypto_agility": {
          "score": 12,
          "note": "OP Stack upgrade via Superchain governance; crypto swap requires coordination with OP Stack family."
        },
        "4b_account_abstraction_key_rotation": {
          "score": 15,
          "note": "Inherits ERC-4337, EIP-7702. Coinbase Smart Wallet uses AA."
        },
        "4c_hard_fork_track_record": {
          "score": 12,
          "note": "Multiple OP Stack upgrades (Fjord, Granite, Holocene) executed via Superchain."
        },
        "4d_hybrid_deployment_readiness": {
          "score": 9,
          "note": "Follows Ethereum L1 migration; no Base-specific hybrid path."
        }
      },
      "total_artifacts": 2
    },
    "5_deployment_execution": {
      "weight": 0.22,
      "score": 3,
      "sub_scores": {
        "5a_mainnet_pqc_pct": {
          "score": 0,
          "mainnet_pqc_pct": 0,
          "evidence": [],
          "note": "no public artifact found"
        },
        "5b_pqc_code_in_client": {
          "score": 0,
          "note": "no PQC in op-geth"
        },
        "5c_validator_pqc_adoption": {
          "score": 0,
          "note": "Coinbase-operated sequencer; no PQC keys"
        },
        "5d_published_milestones_count": {
          "score": 0,
          "count": 0,
          "note": "no PQC milestones"
        },
        "5e_pqc_washing_delta": {
          "score": 3,
          "ratio": 1,
          "note": "No PQC announcements"
        }
      },
      "total_artifacts": 0
    },
    "6_supply_chain_vendor_readiness": {
      "weight": 0.25,
      "score": 10,
      "sub_scores": {
        "6a_wallet": {
          "score": 3,
          "top3": [
            "Coinbase Smart Wallet",
            "MetaMask",
            "Rabby"
          ],
          "pqc_roadmap_count": 0,
          "evidence": []
        },
        "6b_bridge": {
          "score": 2,
          "top3": [
            "Native Base Bridge",
            "Across",
            "LayerZero"
          ],
          "pqc_roadmap_count": 0,
          "evidence": []
        },
        "6c_custodian": {
          "score": 3,
          "top3": [
            "Coinbase Custody",
            "BitGo",
            "Fireblocks"
          ],
          "pqc_roadmap_count": 0,
          "evidence": []
        },
        "6d_rpc_hsm": {
          "score": 2,
          "top3": [
            "Base RPC (Coinbase)",
            "Alchemy",
            "QuickNode"
          ],
          "pqc_roadmap_count": 0,
          "evidence": []
        }
      },
      "total_artifacts": 1
    },
    "7_governance_coordination": {
      "weight": 0.1,
      "score": 58,
      "sub_scores": {
        "7a_validator_stake_distribution": {
          "score": 8,
          "note": "Centralized Coinbase sequencer. No validator set."
        },
        "7b_upgrade_cadence_under_pressure": {
          "score": 18,
          "note": "OP Stack Superchain upgrades executed smoothly. Coinbase security team mature."
        },
        "7c_named_coordination_lead": {
          "score": 18,
          "note": "Coinbase (Jesse Pollak, Base leader) + Optimism Collective Superchain."
        },
        "7d_adversarial_coordination_precedent": {
          "score": 14,
          "note": "Coinbase incident response experienced (parent company is public, security incidents handled)."
        }
      },
      "total_artifacts": 3
    }
  },
  "gates": {
    "hybrid_deployment": "FAIL",
    "evidence_reconstruction": "PASS",
    "primitive_naming": "PASS"
  },
  "caps_applied": [
    "mosca_cap_60",
    "sutor_stage_cap_2",
    "casado_stage_cap_3",
    "preskill_half_dim2_dim3_dim5_dim6",
    "hybrid_gate_fail_cap_60"
  ],
  "qri": {
    "raw": 16,
    "after_caps": 16,
    "ci_plus_minus": 10,
    "band": 2,
    "band_name": "Acknowledged"
  },
  "migration_stage": 0,
  "mosca_inequality": {
    "X_signature_shelf_life_years": "5-10 (EOA with Smart Wallet AA allows rotation)",
    "Y_migration_time_years_range": "10-15",
    "Z_10pct_year": 2036,
    "Z_50pct_year": 2041,
    "danger_zone_at_50pct": true
  },
  "four_scenario_grid": {
    "quantum_never": {
      "value_preserved_pct": 100,
      "privacy_preserved_pct": 100
    },
    "arrives_suddenly_pre_migration": {
      "value_preserved_pct": 15,
      "privacy_preserved_pct": 5
    },
    "arrives_slowly_post_migration": {
      "value_preserved_pct": 85,
      "privacy_preserved_pct": 70
    },
    "arrives_slowly_mid_migration": {
      "value_preserved_pct": 50,
      "privacy_preserved_pct": 30
    }
  },
  "burn_vs_rescue_policy": "undeclared (dependent on Ethereum L1 policy)",
  "pqc_washing_ratio": 1,
  "vendor_tile_summary": {
    "wallet": {
      "top3": [
        "Coinbase Smart Wallet",
        "MetaMask",
        "Rabby"
      ],
      "pqc_roadmap_count": 0
    },
    "bridge": {
      "top3": [
        "Native Base Bridge",
        "Across",
        "LayerZero"
      ],
      "pqc_roadmap_count": 0
    },
    "custodian": {
      "top3": [
        "Coinbase Custody",
        "BitGo",
        "Fireblocks"
      ],
      "pqc_roadmap_count": 0
    },
    "rpc_hsm": {
      "top3": [
        "Base RPC",
        "Alchemy",
        "QuickNode"
      ],
      "pqc_roadmap_count": 0
    }
  },
  "narrative_summary": "Base is Coinbase's OP Stack rollup. Zero Base-specific PQC work; migration path depends on Ethereum L1 + OP Stack Superchain. Coinbase Smart Wallet (AA) and strong corporate incident response give good migration potential, but nothing shipped. Largest L2 by daily users.",
  "evaluator_notes": "Strong governance side (Coinbase + Superchain) potentially accelerates migration IF Ethereum ships PQC. Until then, Band 2 Acknowledged. Custodian tile has highest PQC-awareness potential (Coinbase Custody).",
  "narrative_voiced": "Base is Coinbase's rollup, built on OP Stack, and its quantum plan is whatever Ethereum's plan turns out to be. The interesting asymmetry is that Coinbase Custody is one of the few custodians on this list with any PQC work, so the company behind the chain is ahead of the chain itself."
}