chore: simplify deployment flow

l1-contracts/src/governance/Gerousia.sol

@@ -29,15 +29,13 @@ contract Gerousia is IGerousia {
 
   uint256 public constant LIFETIME_IN_ROUNDS = 5;
 
-  IApella public immutable APELLA;
   IRegistry public immutable REGISTRY;
   uint256 public immutable N;
   uint256 public immutable M;
 
   mapping(address instance => mapping(uint256 roundNumber => RoundAccounting)) public rounds;
 
-  constructor(IApella _apella, IRegistry _registry, uint256 _n, uint256 _m) {
-    APELLA = _apella;
+  constructor(IRegistry _registry, uint256 _n, uint256 _m) {
     REGISTRY = _registry;
     N = _n;
     M = _m;
@@ -120,7 +118,7 @@ contract Gerousia is IGerousia {
 
     emit ProposalPushed(round.leader, _roundNumber);
 
-    require(APELLA.propose(round.leader), Errors.Gerousia__FailedToPropose(round.leader));
+    require(getApella().propose(round.leader), Errors.Gerousia__FailedToPropose(round.leader));
     return true;
   }
 
@@ -152,4 +150,8 @@ contract Gerousia is IGerousia {
   function computeRound(Slot _slot) public view override(IGerousia) returns (uint256) {
     return _slot.unwrap() / M;
   }
+
+  function getApella() public view override(IGerousia) returns (IApella) {
+    return IApella(REGISTRY.getApella());
+  }
 }

l1-contracts/src/governance/Registry.sol

@@ -84,6 +84,14 @@ contract Registry is IRegistry, Ownable {
     return currentSnapshot;
   }
 
+  /**
+   * @notice Returns the address of the apella
+   * @return The apella address
+   */
+  function getApella() external view override(IRegistry) returns (address) {
+    return owner();
+  }
+
   /**
    * @notice Creates a new snapshot of the registry
    *

l1-contracts/src/governance/interfaces/IGerousia.sol

@@ -2,7 +2,7 @@
 pragma solidity >=0.8.27;
 
 import {Slot} from "@aztec/core/libraries/TimeMath.sol";
-
+import {IApella} from "@aztec/governance/interfaces/IApella.sol";
 import {IPayload} from "@aztec/governance/interfaces/IPayload.sol";
 
 interface IGerousia {
@@ -16,4 +16,5 @@ interface IGerousia {
     view
     returns (uint256);
   function computeRound(Slot _slot) external view returns (uint256);
+  function getApella() external view returns (IApella);
 }

l1-contracts/src/governance/interfaces/IRegistry.sol

@@ -34,4 +34,6 @@ interface IRegistry {
   // docs:end:registry_number_of_versions
 
   function isRollupRegistered(address _rollup) external view returns (bool);
+
+  function getApella() external view returns (address);
 }

l1-contracts/test/governance/apella/base.t.sol

@@ -37,15 +37,11 @@ contract ApellaBase is TestBase {
   function setUp() public virtual {
     token = IMintableERC20(address(new TestERC20()));
 
-    // @todo We should be using a bit of create2 magic to do this nicely
-    apella = new Apella(token, address(0));
-    registry = new Registry(address(apella));
-    gerousia = new Gerousia(apella, registry, 677, 1000);
+    registry = new Registry(address(this));
+    gerousia = new Gerousia(registry, 677, 1000);
 
-    // cheeky breeky
-    vm.store(address(apella), 0, bytes32(uint256(uint160(address(gerousia)))));
-
-    assertEq(apella.gerousia(), address(gerousia));
+    apella = new Apella(token, address(gerousia));
+    registry.transferOwnership(address(apella));
 
     {
       CallAssetPayload payload = new CallAssetPayload(token, address(apella));

l1-contracts/test/governance/gerousia/Base.t.sol

@@ -7,15 +7,14 @@ import {Registry} from "@aztec/governance/Registry.sol";
 import {Gerousia} from "@aztec/governance/Gerousia.sol";
 
 import {IPayload} from "@aztec/governance/interfaces/IPayload.sol";
-import {IApella} from "@aztec/governance/interfaces/IApella.sol";
 
 contract FakeApella {
-  address public gerousia;
+  address immutable GEROUSIA;
 
   mapping(IPayload => bool) public proposals;
 
-  function setGerousia(address _gerousia) external {
-    gerousia = _gerousia;
+  constructor(address _gerousia) {
+    GEROUSIA = _gerousia;
   }
 
   function propose(IPayload _proposal) external returns (bool) {
@@ -31,10 +30,10 @@ contract GerousiaBase is Test {
 
   function setUp() public virtual {
     registry = new Registry(address(this));
-    apella = new FakeApella();
 
-    gerousia = new Gerousia(IApella(address(apella)), registry, 667, 1000);
+    gerousia = new Gerousia(registry, 667, 1000);
+    apella = new FakeApella(address(gerousia));
 
-    apella.setGerousia(address(gerousia));
+    registry.transferOwnership(address(apella));
   }
 }

l1-contracts/test/governance/gerousia/constructor.t.sol

@@ -5,10 +5,8 @@ import {Test} from "forge-std/Test.sol";
 import {Gerousia} from "@aztec/governance/Gerousia.sol";
 import {Errors} from "@aztec/governance/libraries/Errors.sol";
 import {IRegistry} from "@aztec/governance/interfaces/IRegistry.sol";
-import {IApella} from "@aztec/governance/interfaces/IApella.sol";
 
 contract ConstructorTest is Test {
-  IApella internal constant APELLA = IApella(address(0x01));
   IRegistry internal constant REGISTRY = IRegistry(address(0x02));
 
   function test_WhenNIsLessThanOrEqualHalfOfM(uint256 _n, uint256 _m) external {
@@ -17,7 +15,7 @@ contract ConstructorTest is Test {
     uint256 n = bound(_n, 0, _m / 2);
 
     vm.expectRevert(abi.encodeWithSelector(Errors.Gerousia__InvalidNAndMValues.selector, n, _m));
-    new Gerousia(APELLA, REGISTRY, n, _m);
+    new Gerousia(REGISTRY, n, _m);
   }
 
   function test_WhenNLargerThanM(uint256 _n, uint256 _m) external {
@@ -26,7 +24,7 @@ contract ConstructorTest is Test {
     uint256 n = bound(_n, m + 1, type(uint256).max);
 
     vm.expectRevert(abi.encodeWithSelector(Errors.Gerousia__NCannotBeLargerTHanM.selector, n, m));
-    new Gerousia(APELLA, REGISTRY, n, m);
+    new Gerousia(REGISTRY, n, m);
   }
 
   function test_WhenNIsGreatherThanHalfOfM(uint256 _n, uint256 _m) external {
@@ -35,9 +33,8 @@ contract ConstructorTest is Test {
     uint256 m = bound(_m, 1, type(uint256).max);
     uint256 n = bound(_n, m / 2 + 1, m);
 
-    Gerousia g = new Gerousia(APELLA, REGISTRY, n, m);
+    Gerousia g = new Gerousia(REGISTRY, n, m);
 
-    assertEq(address(g.APELLA()), address(APELLA));
     assertEq(address(g.REGISTRY()), address(REGISTRY));
     assertEq(g.N(), n);
     assertEq(g.M(), m);

l1-contracts/test/governance/gerousia/pushProposal.t.sol

@@ -29,6 +29,7 @@ contract PushProposalTest is GerousiaBase {
 
   modifier givenCanonicalInstanceHoldCode() {
     leonidas = new Leonidas(address(this));
+    vm.prank(registry.getApella());
     registry.upgrade(address(leonidas));
 
     // We jump into the future since slot 0, will behave as if already voted in
@@ -196,6 +197,7 @@ contract PushProposalTest is GerousiaBase {
 
     // When using a new registry we change the gerousia's interpetation of time :O
     Leonidas freshInstance = new Leonidas(address(this));
+    vm.prank(registry.getApella());
     registry.upgrade(address(freshInstance));
 
     // The old is still there, just not executable.

l1-contracts/test/governance/gerousia/vote.t.sol

@@ -36,6 +36,7 @@ contract VoteTest is GerousiaBase {
 
   modifier givenCanonicalRollupHoldCode() {
     leonidas = new Leonidas(address(this));
+    vm.prank(registry.getApella());
     registry.upgrade(address(leonidas));
 
     // We jump into the future since slot 0, will behave as if already voted in
@@ -129,6 +130,7 @@ contract VoteTest is GerousiaBase {
     uint256 yeaBefore = gerousia.yeaCount(address(leonidas), leonidasRound, proposal);
 
     Leonidas freshInstance = new Leonidas(address(this));
+    vm.prank(registry.getApella());
     registry.upgrade(address(freshInstance));
 
     vm.warp(Timestamp.unwrap(freshInstance.getTimestampForSlot(Slot.wrap(1))));