diff --git a/src/seeder/bitcoin.h b/src/seeder/bitcoin.h
--- a/src/seeder/bitcoin.h
+++ b/src/seeder/bitcoin.h
@@ -20,9 +20,6 @@
 // message.
 static const unsigned int ADDR_SOFT_CAP = 1000;
 
-// The network magic to use.
-extern CMessageHeader::MessageMagic netMagic;
-
 enum class PeerMessagingState {
     AwaitingMessages,
     Finished,
diff --git a/src/seeder/bitcoin.cpp b/src/seeder/bitcoin.cpp
--- a/src/seeder/bitcoin.cpp
+++ b/src/seeder/bitcoin.cpp
@@ -12,9 +12,6 @@
 
 #include <algorithm>
 
-// The network magic to use.
-CMessageHeader::MessageMagic netMagic = {{0xe3, 0xe1, 0xf3, 0xe8}};
-
 #define BITCOIN_SEED_NONCE 0x0539a019ca550825ULL
 
 static const uint32_t allones(-1);
@@ -24,7 +21,7 @@
         AbortMessage();
     }
     nHeaderStart = vSend.size();
-    vSend << CMessageHeader(netMagic, pszCommand, 0);
+    vSend << CMessageHeader(Params().NetMagic(), pszCommand, 0);
     nMessageStart = vSend.size();
     // tfm::format(std::cout, "%s: SEND %s\n", ToString(you),
     // pszCommand);
@@ -171,6 +168,8 @@
         return false;
     }
 
+    const CMessageHeader::MessageMagic netMagic = Params().NetMagic();
+
     do {
         CDataStream::iterator pstart = std::search(
             vRecv.begin(), vRecv.end(), BEGIN(netMagic), END(netMagic));
diff --git a/src/seeder/main.cpp b/src/seeder/main.cpp
--- a/src/seeder/main.cpp
+++ b/src/seeder/main.cpp
@@ -520,7 +520,6 @@
     }
     bool fDNS = true;
     tfm::format(std::cout, "Using %s.\n", gArgs.GetChainName());
-    netMagic = Params().NetMagic();
     if (opts.ns.empty()) {
         tfm::format(std::cout, "No nameserver set. Not starting DNS server.\n");
         fDNS = false;