diff --git a/beacon_node/beacon_chain/test_harness/src/lib.rs b/beacon_node/beacon_chain/test_harness/src/lib.rs
index 0703fd4a5..f58c1b598 100644
--- a/beacon_node/beacon_chain/test_harness/src/lib.rs
+++ b/beacon_node/beacon_chain/test_harness/src/lib.rs
@@ -15,7 +15,7 @@
 //! let validator_count = 8;
 //! let spec = ChainSpec::few_validators();
 //!
-//! let mut harness = BeaconChainHarness::new(spec, validator_count);
+//! let mut harness = BeaconChainHarness::new(spec, validator_count, None, true);
 //!
 //! harness.advance_chain_with_block();
 //!
diff --git a/beacon_node/beacon_chain/test_harness/tests/chain.rs b/beacon_node/beacon_chain/test_harness/tests/chain.rs
index e72c3a5aa..e5a52a314 100644
--- a/beacon_node/beacon_chain/test_harness/tests/chain.rs
+++ b/beacon_node/beacon_chain/test_harness/tests/chain.rs
@@ -10,7 +10,7 @@ fn it_can_build_on_genesis_block() {
     let spec = ChainSpec::few_validators();
     let validator_count = 8;
 
-    let mut harness = BeaconChainHarness::new(spec, validator_count as usize);
+    let mut harness = BeaconChainHarness::new(spec, validator_count as usize, None, true);
 
     harness.advance_chain_with_block();
 }
@@ -25,7 +25,7 @@ fn it_can_produce_past_first_epoch_boundary() {
 
     debug!("Starting harness build...");
 
-    let mut harness = BeaconChainHarness::new(spec, validator_count);
+    let mut harness = BeaconChainHarness::new(spec, validator_count, None, true);
 
     debug!("Harness built, tests starting..");
 
diff --git a/beacon_node/src/main.rs b/beacon_node/src/main.rs
index 072315b6b..c05438cfb 100644
--- a/beacon_node/src/main.rs
+++ b/beacon_node/src/main.rs
@@ -17,8 +17,12 @@ use db::{
 use fork_choice::BitwiseLMDGhost;
 use slog::{error, info, o, Drain};
 use slot_clock::SystemTimeSlotClock;
+use ssz::TreeHash;
 use std::sync::Arc;
-use types::{ChainSpec, Deposit, DepositData, DepositInput, Eth1Data, Hash256, Keypair};
+use types::{
+    beacon_state::BeaconStateBuilder, BeaconBlock, ChainSpec, Deposit, DepositData, DepositInput,
+    Eth1Data, Hash256, Keypair,
+};
 
 fn main() {
     let decorator = slog_term::TermDecorator::new().build();
@@ -97,7 +101,8 @@ fn main() {
         .iter()
         .map(|_| Keypair::random())
         .collect();
-    let initial_validator_deposits = keypairs
+
+    let initial_validator_deposits: Vec<Deposit> = keypairs
         .iter()
         .map(|keypair| Deposit {
             branch: vec![], // branch verification is not specified.
@@ -114,14 +119,19 @@ fn main() {
         })
         .collect();
 
+    let mut state_builder = BeaconStateBuilder::new(genesis_time, latest_eth1_data, &spec);
+    state_builder.process_initial_deposits(&initial_validator_deposits, &spec);
+    let genesis_state = state_builder.build(&spec).unwrap();
+    let state_root = Hash256::from_slice(&genesis_state.hash_tree_root());
+    let genesis_block = BeaconBlock::genesis(state_root, &spec);
+
     // Genesis chain
-    let _chain_result = BeaconChain::genesis(
+    let _chain_result = BeaconChain::from_genesis(
         state_store.clone(),
         block_store.clone(),
         slot_clock,
-        genesis_time,
-        latest_eth1_data,
-        initial_validator_deposits,
+        genesis_state,
+        genesis_block,
         spec,
         fork_choice,
     );
diff --git a/eth2/types/src/beacon_state/builder.rs b/eth2/types/src/beacon_state/builder.rs
index c36cd11f4..22ca3e622 100644
--- a/eth2/types/src/beacon_state/builder.rs
+++ b/eth2/types/src/beacon_state/builder.rs
@@ -53,7 +53,8 @@ impl BeaconStateBuilder {
 
     /// Instantiate the validator registry from a YAML file.
     ///
-    /// This skips a lot of signing and verification, useful for fast test setups.
+    /// This skips a lot of signing and verification, useful if signing and verification has been
+    /// completed previously.
     ///
     /// Spec v0.4.0
     pub fn import_existing_validators(