diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..e80ffd8
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,6 @@
+[submodule "lib/forge-std"]
+	path = lib/forge-std
+	url = https://github.com/foundry-rs/forge-std
+[submodule "lib/openzeppelin-contracts"]
+	path = lib/openzeppelin-contracts
+	url = https://github.com/openzeppelin/openzeppelin-contracts
diff --git a/foundry.toml b/foundry.toml
index 4ff40c4..d3dc103 100644
--- a/foundry.toml
+++ b/foundry.toml
@@ -1,6 +1,3 @@
 [profile.default]
-src = "src"
-out = "out"
-libs = ["lib"]
-
-# See more config options https://github.com/foundry-rs/foundry/tree/master/config
\ No newline at end of file
+libs = ['node_modules', 'lib']
+test = 'test'
\ No newline at end of file
diff --git a/lib/forge-std b/lib/forge-std
new file mode 160000
index 0000000..74cfb77
--- /dev/null
+++ b/lib/forge-std
@@ -0,0 +1 @@
+Subproject commit 74cfb77e308dd188d2f58864aaf44963ae6b88b1
diff --git a/lib/openzeppelin-contracts b/lib/openzeppelin-contracts
new file mode 160000
index 0000000..e50c24f
--- /dev/null
+++ b/lib/openzeppelin-contracts
@@ -0,0 +1 @@
+Subproject commit e50c24f5839db17f46991478384bfda14acfb830
diff --git a/script/Counter.s.sol b/script/Bootstrap.s.sol
similarity index 100%
rename from script/Counter.s.sol
rename to script/Bootstrap.s.sol
diff --git a/src/Bootstrap.sol b/src/Bootstrap.sol
new file mode 100644
index 0000000..74be2cc
--- /dev/null
+++ b/src/Bootstrap.sol
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.13;
+
+import "openzeppelin-contracts/contracts/access/Ownable.sol";
+import "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";
+
+contract Bootstrap is Ownable {
+    IERC20 public immutable token;
+
+    uint256 public immutable rewardRate;
+
+    mapping(uint8 => mapping(uint256 => bytes)) enrIndex;
+
+    mapping(uint8 => uint256) shardEnrIndex;
+
+    mapping(uint8 => mapping(uint256 => mapping(bytes => bool))) public shardEnrs;
+
+    uint8 public immutable shardCount;
+
+    mapping(address => bool) public arbiters;
+
+    struct Challenge {
+        uint256 uptime;
+        address arbiter;
+    }
+
+    modifier onlyArbiter() {
+        require(arbiters[msg.sender] == true, "Arbiter: you aren't");
+        _;
+    }
+
+    // map epoch => shard => enr => uptime struct
+    mapping(uint256 => mapping(uint8 => mapping(uint256 => mapping(bytes => Challenge)))) public challenges;
+
+    event NewEnr(uint8 shardId, bytes enr);
+    event RemovedEnr(uint8 shardId, bytes enr, Challenge challenge);
+
+    constructor(address _token, uint8 _shardCount, address[] memory _arbiters, uint256 _rewardRate) {
+        token = IERC20(_token);
+        shardCount = _shardCount;
+        for (uint8 i = 0; i < _arbiters.length; ++i) {
+            arbiters[_arbiters[i]] = true;
+        }
+        rewardRate = _rewardRate;
+    }
+
+    function registerEnr(uint8 shard, bytes memory enr) external {
+        require(shard <= shardCount, "shard invalid");
+
+        shardEnrs[shard][shardEnrIndex[shard]][enr] = true;
+        ++shardEnrIndex[shard];
+
+        emit NewEnr(shard, enr);
+    }
+
+    function getEnrForShard(uint8 shard) public view returns (bytes[] memory) {
+        uint256 shardSize = shardEnrIndex[shard];
+        bytes[] memory t = new bytes[](shardSize);
+        for (uint256 i = 0; i < shardSize; i++) {
+            bytes memory enr = enrIndex[shard][i];
+            t[i] = enr;
+        }
+        return t;
+    }
+
+    function challengeEnrUptime(uint8 shard, bytes memory enr, uint256 uptime) public onlyArbiter {
+        uint256 epoch = block.number % 10; // todo define epochs
+        challenges[epoch][shard][shardEnrIndex[shard]][enr] = Challenge({uptime: uptime, arbiter: msg.sender});
+    }
+
+    function removeEnr(uint256 epoch, uint8 shard, bytes memory enr) public onlyOwner {
+        Challenge storage c = challenges[epoch][shard][shardEnrIndex[shard]][enr];
+        require(c.uptime >= 0, "RemoveEnr: 0 uptime");
+        require(c.arbiter != address(0), "RemoveEnr: 0 address");
+
+        require(token.balanceOf(address(this)) >= rewardRate, "RemoveEnr: no balance");
+
+        shardEnrs[shard][shardEnrIndex[shard]][enr] = false;
+        emit RemovedEnr(shard, enr, c);
+
+        // add balance to arbiter's
+        token.transfer(c.arbiter, rewardRate);
+    }
+}
diff --git a/src/Counter.sol b/src/Counter.sol
deleted file mode 100644
index aded799..0000000
--- a/src/Counter.sol
+++ /dev/null
@@ -1,14 +0,0 @@
-// SPDX-License-Identifier: UNLICENSED
-pragma solidity ^0.8.13;
-
-contract Counter {
-    uint256 public number;
-
-    function setNumber(uint256 newNumber) public {
-        number = newNumber;
-    }
-
-    function increment() public {
-        number++;
-    }
-}
diff --git a/test/Bootstrap.t.sol b/test/Bootstrap.t.sol
new file mode 100644
index 0000000..27896e0
--- /dev/null
+++ b/test/Bootstrap.t.sol
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.13;
+
+import "openzeppelin-contracts/contracts/token/ERC20/ERC20.sol";
+import "forge-std/Test.sol";
+import "../src/Bootstrap.sol";
+
+contract BootstrapTest is Test {
+    ERC20 public token;
+    Bootstrap public bootstrap;
+
+    function setUp() public {
+        token = new ERC20("bootstrap_test", "BOOT");
+        bootstrap = new Bootstrap(address(token));
+    }
+
+    function testSanity() public {
+        assertEq(address(this), bootstrap.owner());
+        assertEq(address(token), address(bootstrap.token()));
+    }
+}
diff --git a/test/Counter.t.sol b/test/Counter.t.sol
deleted file mode 100644
index 30235e8..0000000
--- a/test/Counter.t.sol
+++ /dev/null
@@ -1,24 +0,0 @@
-// SPDX-License-Identifier: UNLICENSED
-pragma solidity ^0.8.13;
-
-import "forge-std/Test.sol";
-import "../src/Counter.sol";
-
-contract CounterTest is Test {
-    Counter public counter;
-
-    function setUp() public {
-        counter = new Counter();
-        counter.setNumber(0);
-    }
-
-    function testIncrement() public {
-        counter.increment();
-        assertEq(counter.number(), 1);
-    }
-
-    function testSetNumber(uint256 x) public {
-        counter.setNumber(x);
-        assertEq(counter.number(), x);
-    }
-}