diff --git a/.gitmodules b/.gitmodules
index 216f76996..072bce75e 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -200,3 +200,7 @@
 [submodule "vendor/gnosis-chain-configs"]
 	path = vendor/gnosis-chain-configs
 	url = https://github.com/zah/gnosis-chain-configs.git
+[submodule "vendor/capella-testnets"]
+	path = vendor/capella-testnets
+	url = https://github.com/ethpandaops/withdrawals-testnet.git
+	branch = master
diff --git a/Makefile b/Makefile
index b9493c2a8..180b5e86b 100644
--- a/Makefile
+++ b/Makefile
@@ -593,6 +593,14 @@ sepolia-dev-deposit: | sepolia-build deposit_contract
 clean-sepolia:
 	$(call CLEAN_NETWORK,sepolia)
 
+### Capella devnets
+
+capella-devnet-2:
+	tmuxinator start -p scripts/tmuxinator-el-cl-pair-in-devnet.yml network="vendor/capella-testnets/withdrawal-devnet-2/custom_config_data"
+
+clean-capella-devnet-2:
+	scripts/clean-devnet-dir.sh vendor/capella-testnets/withdrawal-devnet-2/custom_config_data
+
 ###
 ### Gnosis chain binary
 ###
diff --git a/beacon_chain/eth1/eth1_monitor.nim b/beacon_chain/eth1/eth1_monitor.nim
index 318aa81a8..de3cf9870 100644
--- a/beacon_chain/eth1/eth1_monitor.nim
+++ b/beacon_chain/eth1/eth1_monitor.nim
@@ -1370,14 +1370,14 @@ proc findTerminalBlock(provider: Web3DataProviderRef,
     return value
 
   # Block A follows, B leads.
-  var
-    a = awaitWithRetries(
-      provider.web3.provider.eth_getBlockByNumber("latest", false))
-    b = await next(a)
+  var a = awaitWithRetries(
+    provider.web3.provider.eth_getBlockByNumber("latest", false))
 
   if a.number.uint64 == 0 and a.totalDifficulty >= ttd:
     return a
 
+  var b = await next(a)
+
   while true:
     let one = a.totalDifficulty >= ttd
     let two = b.totalDifficulty >= ttd
diff --git a/beacon_chain/networking/network_metadata.nim b/beacon_chain/networking/network_metadata.nim
index e931172bb..31a335f09 100644
--- a/beacon_chain/networking/network_metadata.nim
+++ b/beacon_chain/networking/network_metadata.nim
@@ -156,8 +156,7 @@ proc loadEth2NetworkMetadata*(path: string, eth1Network = none(Eth1Network)): Et
 
       depositContractBlockHash = if depositContractBlockHashStr.len > 0:
         Eth2Digest.strictParse(depositContractBlockHashStr)
-      elif (not runtimeConfig.DEPOSIT_CONTRACT_ADDRESS.isDefaultValue) and
-            depositContractBlock != 0:
+      elif not runtimeConfig.DEPOSIT_CONTRACT_ADDRESS.isDefaultValue:
         raise newException(ValueError,
           "A network with deposit contract should specify the " &
           "deposit contract deployment block hash in a file " &
diff --git a/scripts/bash_utils.sh b/scripts/bash_utils.sh
new file mode 100644
index 000000000..045581e4f
--- /dev/null
+++ b/scripts/bash_utils.sh
@@ -0,0 +1,17 @@
+if [ -z "${BASH_UTILS_SOURCED:-}" ]; then
+BASH_UTILS_SOURCED=1
+
+VERBOSE="0"
+
+log() {
+  if [[ "${VERBOSE}" -ge "1" ]]; then
+    echo "${@}"
+  fi
+}
+
+run() {
+  echo Launching: $*
+  $*
+}
+
+fi
diff --git a/scripts/clean-devnet-dir.sh b/scripts/clean-devnet-dir.sh
new file mode 100755
index 000000000..3dfbf9f8a
--- /dev/null
+++ b/scripts/clean-devnet-dir.sh
@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+
+if [ -z "$1" ]; then
+  echo "Usage: run-devnet-el-cl-pair.sh <network-metadata-dir>"
+  exit 1
+fi
+
+if [ ! -d "$1" ]; then
+  echo "Please supply a valid network metadata directory"
+  exit 1
+fi
+
+set -Eeu
+
+NETWORK=$(cd "$1"; pwd)
+
+cd $(dirname "$0")
+
+source ./repo_paths.sh
+rm -rf "$(data_dir_for_network)"
diff --git a/scripts/detect_platform.sh b/scripts/detect_platform.sh
new file mode 100644
index 000000000..82bd975ba
--- /dev/null
+++ b/scripts/detect_platform.sh
@@ -0,0 +1,15 @@
+if [ -z "${DETECT_PLATFORM_SOURCED:-}" ]; then
+DETECT_PLATFORM_SOURCED=1
+
+# OS detection
+OS="linux"
+if uname | grep -qi darwin; then
+  OS="macos"
+elif uname | grep -qiE "mingw|msys"; then
+  OS="windows"
+fi
+
+# Architecture detection
+ARCH="$(uname -m)"
+
+fi
diff --git a/scripts/geth_binaries.sh b/scripts/geth_binaries.sh
new file mode 100644
index 000000000..d967672ae
--- /dev/null
+++ b/scripts/geth_binaries.sh
@@ -0,0 +1,110 @@
+if [ -z "${GETH_BINARIES_SOURCED:-}" ]; then
+GETH_BINARIES_SOURCED=1
+
+SCRIPTS_DIR="$(dirname "${BASH_SOURCE[0]}")"
+BUILD_DIR="$(cd "$SCRIPTS_DIR/../build"; pwd)"
+
+source "${SCRIPTS_DIR}/detect_platform.sh"
+source "${SCRIPTS_DIR}/bash_utils.sh"
+
+: ${CURL_BINARY:="curl"}
+: ${STABLE_GETH_BINARY:="${BUILD_DIR}/downloads/geth"}
+: ${GETH_CAPELLA_BINARY:="${BUILD_DIR}/downloads/geth_capella"}
+: ${GETH_EIP_4844_BINARY:="${BUILD_DIR}/downloads/geth_eip4844"}
+
+download_geth_stable() {
+  if [[ ! -e "${STABLE_GETH_BINARY}" ]]; then
+    GETH_VERSION="1.10.26-e5eb32ac"  
+    GETH_URL="https://gethstore.blob.core.windows.net/builds/"
+
+    case "${OS}-${ARCH}" in
+      linux-amd64|linux-x86_64)
+        GETH_TARBALL="geth-linux-amd64-${GETH_VERSION}.tar.gz"
+        ;;
+      linux-arm64|linux-aarch64)
+        GETH_TARBALL="geth-linux-arm64-${GETH_VERSION}.tar.gz"
+        ;;
+      macos-amd64|macos-x86_64)
+        GETH_TARBALL="geth-darwin-amd64-${GETH_VERSION}.tar.gz"
+        ;;
+      macos-arm64|macos-aarch64)
+        # There is no official binary for macOS/ARM at the moment
+        # The AMD64 binary should work under Rosetta
+        GETH_TARBALL="geth-darwin-amd64-${GETH_VERSION}.tar.gz"
+        ;;
+      windows-amd64|windows-x86_64)
+        GETH_TARBALL="geth-windows-amd64-${GETH_VERSION}.zip"
+        ;;
+      *)
+        echo "No Geth binaries available for platform: ${OS}-${ARCH}"
+        exit 1
+        ;;
+    esac
+
+    log "Downloading Geth binary"
+
+    "$CURL_BINARY" -sSLO "$GETH_URL/$GETH_TARBALL"
+    local tmp_extract_dir
+    tmp_extract_dir=$(mktemp -d geth-stable-tarball-XXX)
+    CLEANUP_DIRS+=("$tmp_extract_dir")
+    tar -xzf "$GETH_TARBALL" -C "$tmp_extract_dir" --strip-components=1
+    mkdir -p "$(dirname "$STABLE_GETH_BINARY")"
+    mv "$tmp_extract_dir/geth" "$STABLE_GETH_BINARY"
+    chmod +x "$STABLE_GETH_BINARY"
+  fi
+}
+
+download_status_geth_binary() {
+  BINARY_NAME="$1"
+  BINARY_FS_PATH="$2"
+
+  if [[ ! -e "${BINARY_FS_PATH}" ]]; then
+    case "${OS}-${ARCH}" in
+      linux-amd64|linux-x86_64)
+        GETH_PLATFORM=linux-amd64
+        ;;
+      linux-arm64|linux-aarch64)
+        GETH_PLATFORM=linux-arm64
+        ;;
+      macos-amd64|macos-x86_64)
+        GETH_PLATFORM=macos-amd64
+        ;;
+      macos-arm64|macos-aarch64)
+        GETH_PLATFORM=macos-arm64
+        ;;
+      windows-amd64|windows-x86_64)
+        GETH_PLATFORM=windows-amd64
+        ;;
+      *)
+        echo "No Status Geth binaries available for platform: ${OS}-${ARCH}"
+        exit 1
+        ;;
+    esac
+
+    log "Downloading Status geth binary ($1)"
+
+    GETH_TARBALL_NAME="geth-binaries-${GETH_PLATFORM}.tar.gz"
+    GETH_TARBALL_URL="https://github.com/status-im/nimbus-simulation-binaries/releases/download/latest/${GETH_TARBALL_NAME}"
+    GETH_BINARY_IN_TARBALL="geth/${BINARY_NAME}/geth"
+
+    "$CURL_BINARY" -o "$GETH_TARBALL_NAME" -sSL "$GETH_TARBALL_URL"
+    local tmp_extract_dir
+    tmp_extract_dir=$(mktemp -d geth-status-tarball-XXX)
+    CLEANUP_DIRS+=("$tmp_extract_dir")
+    tar -xzf "$GETH_TARBALL_NAME" -C "$tmp_extract_dir" --strip-components 2 \
+      "$GETH_BINARY_IN_TARBALL"
+    mkdir -p "$(dirname "$BINARY_FS_PATH")"
+    mv "$tmp_extract_dir/geth" "$BINARY_FS_PATH"
+    chmod +x "$BINARY_FS_PATH"
+  fi
+}
+
+download_geth_capella() {
+  download_status_geth_binary withdrawals-timestamp "$GETH_CAPELLA_BINARY"
+}
+
+download_geth_eip_4844() {
+  download_status_geth_binary eip-4844 "$GETH_EIP_4844_BINARY"
+}
+
+fi
diff --git a/scripts/launch_local_testnet.sh b/scripts/launch_local_testnet.sh
index 37f33e850..e0e0e70d3 100755
--- a/scripts/launch_local_testnet.sh
+++ b/scripts/launch_local_testnet.sh
@@ -478,6 +478,7 @@ download_geth() {
 
   if [[ ! -e "build/${GETH_BINARY}" ]]; then
     log "Downloading Geth binary"
+    mkdir -p "build"
     pushd "build" >/dev/null
     "${CURL_BINARY}" -sSLO "${GETH_URL}/${GETH_TARBALL}"
     local tmp_extract_dir
diff --git a/scripts/repo_paths.sh b/scripts/repo_paths.sh
new file mode 100644
index 000000000..ccd817de7
--- /dev/null
+++ b/scripts/repo_paths.sh
@@ -0,0 +1,24 @@
+if [ -z "${REPO_PATHS_SOURCED:-}" ]; then
+REPO_PATHS_SOURCED=1
+
+SCRIPTS_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd)
+BUILD_DIR=$(cd "$SCRIPTS_DIR/../build" &> /dev/null && pwd)
+
+data_dir_for_network() {
+  NETWORK_ID=$(cat "$NETWORK/genesis.json" | jq '.config.chainId')
+  echo "$BUILD_DIR/data/$NETWORK_ID"
+}
+
+create_data_dir_for_network() {
+  NETWORK_DIR=$(data_dir_for_network)
+  mkdir -p "$NETWORK_DIR"
+  echo "$NETWORK_DIR"
+}
+
+create_jwt_token() {
+  if [ ! -f "$1" ]; then
+    openssl rand -hex 32 | tr -d "\n" >  "$1"
+  fi
+}
+
+fi
diff --git a/scripts/run-catalyst.sh b/scripts/run-catalyst.sh
deleted file mode 100755
index 0f1b76aab..000000000
--- a/scripts/run-catalyst.sh
+++ /dev/null
@@ -1,56 +0,0 @@
-#!/usr/bin/env bash
-# set -Eeuo pipefail
-
-# https://notes.ethereum.org/rmVErCfCRPKGqGkUe89-Kg
-
-# Genesis block hash: 0xfoobar
-# To start miner, run miner.start()
-# To increase verbosity: debug.verbosity(4)
-
-GENESISJSON=$(mktemp)
-GETHDATADIR=$(mktemp -d)
-
-echo \{\
-	\"config\": \{\
-		\"chainId\":1,\
-		\"homesteadBlock\":0,\
-		\"eip150Block\":0,\
-		\"eip155Block\":0,\
-		\"eip158Block\":0,\
-		\"byzantiumBlock\":0,\
-		\"constantinopleBlock\":0,\
-		\"petersburgBlock\":0,\
-		\"istanbulBlock\":0,\
-		\"muirGlacierBlock\":0,\
-		\"berlinBlock\":0,\
-		\"londonBlock\":0,\
-		\"clique\": \{\
-			\"period\": 5,\
-			\"epoch\": 30000\
-		\},\
-		\"terminalTotalDifficulty\":0\
-	\},\
-	\"nonce\":\"0x42\",\
-	\"timestamp\":\"0x0\",\
-	\"extraData\":\"0x0000000000000000000000000000000000000000000000000000000000000000a94f5374fce5edbc8e2a8697c15331677e6ebf0b0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000\",\
-	\"gasLimit\":\"0x1C9C380\",\
-	\"difficulty\":\"0x400000000\",\
-	\"mixHash\":\"0x0000000000000000000000000000000000000000000000000000000000000000\",\
-	\"coinbase\":\"0x0000000000000000000000000000000000000000\",\
-	\"alloc\":\{\
-		\"0xa94f5374fce5edbc8e2a8697c15331677e6ebf0b\":\{\"balance\":\"0x6d6172697573766477000000\"\} \
-	\},\
-	\"number\":\"0x0\",\
-	\"gasUsed\":\"0x0\",\
-	\"parentHash\":\"0x0000000000000000000000000000000000000000000000000000000000000000\",\
-	\"baseFeePerGas\":\"0x7\"\
-\} > "${GENESISJSON}"
-
-# Initialize the genesis
-~/go-ethereum/build/bin/geth --http --ws -http.api "engine" --datadir "${GETHDATADIR}" init "${GENESISJSON}"
-
-# Import the signing key (press enter twice for empty password)
-~/go-ethereum/build/bin/geth --http --ws -http.api "engine" --datadir "${GETHDATADIR}" account import <(echo 45a915e4d060149eb4365960e6a7a45f334393093061116b197e3240065ff2d8)
-
-# Start the node (and press enter once to unlock the account)
-~/go-ethereum/build/bin/geth --http --ws --http.api "eth,net,engine" -ws.api "eth,net,engine" --datadir "${GETHDATADIR}" --allow-insecure-unlock --unlock "0xa94f5374fce5edbc8e2a8697c15331677e6ebf0b" --password "" --nodiscover console
diff --git a/scripts/run-geth-el.sh b/scripts/run-geth-el.sh
deleted file mode 100755
index dfaf1e83a..000000000
--- a/scripts/run-geth-el.sh
+++ /dev/null
@@ -1,52 +0,0 @@
-#!/usr/bin/env bash
-# Via Adrian Sutton
-
-if [ -z "$1" ]; then
-  echo "Usage: run-geth-el.sh <network-metadata-dir>"
-  exit 1
-fi
-
-set -Eeu
-
-NETWORK=$1
-
-NETWORK_ID=$(cat "$NETWORK/genesis.json" | jq '.config.chainId')
-
-GETH=${HOME}/execution_clients/go-ethereum/build/bin/geth
-
-# https://github.com/eth2-clients/merge-testnets/tree/main/kintsugi
-EXECUTION_BOOTNODES=$(awk '{print $1}' "$NETWORK/el_bootnode.txt" | paste -s -d, -)
-
-GETHDATADIR=$(mktemp -d)
-GENESISJSON="${NETWORK}/genesis.json"
-
-echo "GETHDATADIR = ${GETHDATADIR}"
-
-# Initialize the genesis
-$GETH --http --ws -http.api "engine" --datadir "${GETHDATADIR}" init "${GENESISJSON}"
-
-# Import the signing key (press enter twice for empty password)
-$GETH --http --ws -http.api "engine" --datadir "${GETHDATADIR}" account import <(echo 45a915e4d060149eb4365960e6a7a45f334393093061116b197e3240065ff2d8)
-
-#--password "execution/geth/passfile.txt"
-#--nodekey "execution/signer.key"
-
-$GETH \
-    --http \
-    --http.port 8550 \
-    --http.api "engine,eth,net,admin,web3" \
-    --http.corsdomain="*" \
-    --http.vhosts="*" \
-    --ws \
-    --ws.port 8551 \
-    --ws.api "engine,eth,net,admin,web3" \
-    --allow-insecure-unlock \
-    --datadir "${GETHDATADIR}" \
-    --bootnodes "${EXECUTION_BOOTNODES}" \
-    --port 30308 \
-    --password "" \
-    --syncmode full \
-    --unlock "0xa94f5374fce5edbc8e2a8697c15331677e6ebf0b" \
-    --mine \
-    --networkid $NETWORK_ID \
-    console
diff --git a/scripts/run-geth-in-devnet.sh b/scripts/run-geth-in-devnet.sh
new file mode 100755
index 000000000..afbf5abe5
--- /dev/null
+++ b/scripts/run-geth-in-devnet.sh
@@ -0,0 +1,64 @@
+#!/usr/bin/env bash
+# Via Adrian Sutton
+
+if [ -z "$1" ]; then
+  echo "Usage: run-geth-el.sh <network-metadata-dir>"
+  exit 1
+fi
+
+if [ ! -d "$1" ]; then
+  echo "Please supply a valid network metadata directory"
+  exit 1
+fi
+
+set -Eeu
+
+NETWORK=$(cd "$1"; pwd)
+
+cd $(dirname "$0")
+
+source geth_binaries.sh
+source repo_paths.sh
+
+download_geth_capella
+
+: ${GETH_AUTH_RPC_PORT:=18550}
+: ${GETH_WS_PORT:=18551}
+
+DATA_DIR="$(create_data_dir_for_network "$NETWORK")"
+
+JWT_TOKEN="$DATA_DIR/jwt-token"
+create_jwt_token "$JWT_TOKEN"
+
+NETWORK_ID=$(cat "$NETWORK/genesis.json" | jq '.config.chainId')
+
+EXECUTION_BOOTNODES=""
+if [[ -f "$NETWORK/el_bootnode.txt" ]]; then
+  EXECUTION_BOOTNODES+=$(awk '{print $1}' "$NETWORK/el_bootnode.txt" "$NETWORK/el_bootnode.txt" | paste -s -d, -)
+fi
+
+if [[ -f "$NETWORK/el_bootnodes.txt" ]]; then
+  EXECUTION_BOOTNODES+=$(awk '{print $1}' "$NETWORK/el_bootnodes.txt" "$NETWORK/el_bootnode.txt" | paste -s -d, -)
+fi
+
+GETH_DATA_DIR="$DATA_DIR/geth"
+EXECUTION_GENESIS_JSON="${NETWORK}/genesis.json"
+
+set -x
+
+if [[ ! -d "$GETH_DATA_DIR/geth" ]]; then
+  # Initialize the genesis
+  $GETH_CAPELLA_BINARY --http --ws -http.api "engine" --datadir "${GETH_DATA_DIR}" init "${EXECUTION_GENESIS_JSON}"
+fi
+
+$GETH_CAPELLA_BINARY \
+    --authrpc.port ${GETH_AUTH_RPC_PORT} \
+    --authrpc.jwtsecret "$JWT_TOKEN" \
+    --allow-insecure-unlock \
+    --datadir "${GETH_DATA_DIR}" \
+    --bootnodes "${EXECUTION_BOOTNODES}" \
+    --port 30308 \
+    --password "" \
+    --metrics \
+    --syncmode=full \
+    --networkid $NETWORK_ID
diff --git a/scripts/run-nimbus-eth2-in-withdrawal-testnet.sh b/scripts/run-nimbus-in-devnet.sh
similarity index 95%
rename from scripts/run-nimbus-eth2-in-withdrawal-testnet.sh
rename to scripts/run-nimbus-in-devnet.sh
index 589ecea9e..6a86b061e 100755
--- a/scripts/run-nimbus-eth2-in-withdrawal-testnet.sh
+++ b/scripts/run-nimbus-in-devnet.sh
@@ -30,7 +30,7 @@ create_jwt_token "$JWT_TOKEN"
   --network="$NETWORK" \
   --log-level=DEBUG \
   --data-dir="$DATA_DIR/nimbus_bn" \
-  --el=http://localhost:18550/ \
+  --web3-url=http://localhost:18550/ \
   --rest:on \
   --rest-port=15052 \
   --metrics=on \
diff --git a/scripts/start_geth_nodes.sh b/scripts/start_geth_nodes.sh
index 67e4517b6..16fee8115 100755
--- a/scripts/start_geth_nodes.sh
+++ b/scripts/start_geth_nodes.sh
@@ -26,7 +26,7 @@ for GETH_NUM_NODE in $(seq 0 $(( GETH_NUM_NODES - 1 ))); do
     GETH_DATA_DIRS+=(${GETHDATADIR})
     openssl rand -hex 32 | tr -d "\n" > "${GETHDATADIR}/jwtsecret"
     ${GETH_BINARY} --http --ws -http.api "engine" --datadir "${GETHDATADIR}" init "${GENESISJSON}"
-    ${GETH_BINARY} --http --ws --http.corsdomain '*' --http.api "eth,net,engine" -ws.api "eth,net,engine" --datadir "${GETHDATADIR}" ${DISCOVER} --port ${GETH_NET_PORT} --http.port ${GETH_HTTP_PORT} --ws.port ${GETH_WS_PORT} --authrpc.port ${GETH_AUTH_RPC_PORT} --authrpc.jwtsecret "${GETHDATADIR}/jwtsecret" &> "${DATA_DIR}/geth-log${GETH_NUM_NODE}.txt" &
+    ${GETH_BINARY} --syncmode full --http --ws --http.corsdomain '*' --http.api "eth,net,engine" -ws.api "eth,net,engine" --datadir "${GETHDATADIR}" ${DISCOVER} --port ${GETH_NET_PORT} --http.port ${GETH_HTTP_PORT} --ws.port ${GETH_WS_PORT} --authrpc.port ${GETH_AUTH_RPC_PORT} --authrpc.jwtsecret "${GETHDATADIR}/jwtsecret" &> "${DATA_DIR}/geth-log${GETH_NUM_NODE}.txt" &
     GETH_RETRY=0
     while :; do
         if [[ -S "${GETHDATADIR}/geth.ipc" ]]; then
diff --git a/scripts/tmuxinator-el-cl-pair-in-devnet.yml b/scripts/tmuxinator-el-cl-pair-in-devnet.yml
new file mode 100644
index 000000000..a11a711fb
--- /dev/null
+++ b/scripts/tmuxinator-el-cl-pair-in-devnet.yml
@@ -0,0 +1,11 @@
+name: devnet
+root: .
+windows:
+  - main:
+      layout: main-horizontal
+      # Synchronize all panes of this window, can be enabled before or after the pane commands run.
+      # 'before' represents legacy functionality and will be deprecated in a future release, in favour of 'after'
+      # synchronize: after
+      panes:
+        CL: ./scripts/run-<%= @settings["cl"] or "nimbus" %>-in-devnet.sh <%= @settings["network"] %>
+        EL: ./scripts/run-<%= @settings["el"] or "geth"   %>-in-devnet.sh <%= @settings["network"] %>
diff --git a/vendor/capella-testnets b/vendor/capella-testnets
new file mode 160000
index 000000000..9deb7d566
--- /dev/null
+++ b/vendor/capella-testnets
@@ -0,0 +1 @@
+Subproject commit 9deb7d5663b389243dae6b2d0c902aa221e088f7