diff --git a/eclair-core/src/test/scala/fr/acinq/eclair/wire/CommandCodecsSpec.scala b/eclair-core/src/test/scala/fr/acinq/eclair/wire/CommandCodecsSpec.scala
index 7d8a7fc31..7d82bd95b 100644
--- a/eclair-core/src/test/scala/fr/acinq/eclair/wire/CommandCodecsSpec.scala
+++ b/eclair-core/src/test/scala/fr/acinq/eclair/wire/CommandCodecsSpec.scala
@@ -17,8 +17,14 @@
 package fr.acinq.eclair.wire
 
 import fr.acinq.eclair.channel._
+import fr.acinq.eclair.wire.CommonCodecs.{bytes32, varsizebinarydata}
+import fr.acinq.eclair.wire.FailureMessageCodecs.failureMessageCodec
 import fr.acinq.eclair.{randomBytes, randomBytes32}
 import org.scalatest.funsuite.AnyFunSuite
+import scodec.DecodeResult
+import scodec.bits.BitVector
+import scodec.codecs._
+import shapeless.HNil
 
 /**
  * Created by PM on 31/05/2016.
@@ -40,4 +46,32 @@ class CommandCodecsSpec extends AnyFunSuite {
         assert(msg === decoded.value)
     }
   }
+
+  test("backward compatibility") {
+
+    val data32 = randomBytes32
+    val data123 = randomBytes(123)
+
+      val legacyCmdFulfillCodec =
+        (("id" | int64) ::
+          ("r" | bytes32) ::
+          ("commit" | provide(false)))
+      assert(CommandCodecs.cmdFulfillCodec.decode(legacyCmdFulfillCodec.encode(42 :: data32 :: true :: HNil).require).require ===
+        DecodeResult(CMD_FULFILL_HTLC(42, data32, commit = false, None), BitVector.empty))
+
+    val legacyCmdFailCodec =
+      (("id" | int64) ::
+        ("reason" | either(bool, varsizebinarydata, failureMessageCodec)) ::
+        ("commit" | provide(false)))
+    assert(CommandCodecs.cmdFailCodec.decode(legacyCmdFailCodec.encode(42 :: Left(data123) :: true :: HNil).require).require ===
+      DecodeResult(CMD_FAIL_HTLC(42, Left(data123), commit = false, None), BitVector.empty))
+
+    val legacyCmdFailMalformedCodec =
+      (("id" | int64) ::
+        ("onionHash" | bytes32) ::
+        ("failureCode" | uint16) ::
+        ("commit" | provide(false)))
+    assert(CommandCodecs.cmdFailMalformedCodec.decode(legacyCmdFailMalformedCodec.encode(42 :: data32 :: 456 :: true :: HNil).require).require ===
+      DecodeResult(CMD_FAIL_MALFORMED_HTLC(42, data32, 456, commit = false, None), BitVector.empty))
+  }
 }
diff --git a/eclair-core/src/test/scala/fr/acinq/eclair/wire/CommonCodecsSpec.scala b/eclair-core/src/test/scala/fr/acinq/eclair/wire/CommonCodecsSpec.scala
index 285158483..0af72f2d7 100644
--- a/eclair-core/src/test/scala/fr/acinq/eclair/wire/CommonCodecsSpec.scala
+++ b/eclair-core/src/test/scala/fr/acinq/eclair/wire/CommonCodecsSpec.scala
@@ -20,12 +20,16 @@ import java.net.{Inet4Address, Inet6Address, InetAddress}
 
 import com.google.common.net.InetAddresses
 import fr.acinq.bitcoin.ByteVector32
+import fr.acinq.bitcoin._
 import fr.acinq.bitcoin.Crypto.PrivateKey
+import fr.acinq.eclair.blockchain.fee.FeeratePerKw
 import fr.acinq.eclair.crypto.Hmac256
 import fr.acinq.eclair.wire.CommonCodecs._
 import fr.acinq.eclair.{UInt64, randomBytes32}
 import org.scalatest.funsuite.AnyFunSuite
+import scodec.DecodeResult
 import scodec.bits.{BitVector, HexStringSyntax}
+import scodec.codecs.uint32
 
 /**
   * Created by t-bast on 20/06/2019.
@@ -251,4 +255,10 @@ class CommonCodecsSpec extends AnyFunSuite {
     }
   }
 
+  test("backward compatibility on feerate codec") {
+    val value = 123456
+    val feerate = FeeratePerKw(value sat)
+    assert(feeratePerKw.decode(uint32.encode(value).require).require === DecodeResult(feerate, BitVector.empty))
+  }
+
 }