diff --git a/nim.cfg b/nim.cfg
new file mode 100644
index 0000000..f8e9c30
--- /dev/null
+++ b/nim.cfg
@@ -0,0 +1,4 @@
+# nim.cfg
+@if nimHasWarningObservableStores:
+  warning[ObservableStores]: off
+@end
diff --git a/tests/all_tests.nim b/tests/all_tests.nim
index c06635d..8a6dc3f 100644
--- a/tests/all_tests.nim
+++ b/tests/all_tests.nim
@@ -5,6 +5,8 @@
 #   * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
+{. warning[UnusedImport]:off .}
+
 import
   test,
   test_deposit_contract,
diff --git a/tests/test_logs.nim b/tests/test_logs.nim
index 55185da..36b42d2 100644
--- a/tests/test_logs.nim
+++ b/tests/test_logs.nim
@@ -8,11 +8,11 @@ import random
 pragma solidity >=0.4.25 <0.6.0;
 
 contract LoggerContract {
-    
+
    uint fNum;
-   
+
    event MyEvent(address sender, uint value);
-   
+
 
    function invoke(uint value) public {
        emit MyEvent(msg.sender, value);
@@ -56,7 +56,7 @@ proc test() {.async.} =
     # Now that we have invoked the function `invocationsBefore` let's wait for the transactions to
     # settle and see if we receive the logs after subscription. Note in ganache transactions are
     # processed immediately. With a real eth client we would need to wait for transactions to settle
-  
+
     await sleepAsync(3.seconds)
 
     let notifFut = newFuture[void]()
diff --git a/web3.nim b/web3.nim
index b9c7137..4365233 100644
--- a/web3.nim
+++ b/web3.nim
@@ -44,7 +44,7 @@ type
     historicalEventsProcessed: bool
     removed: bool
 
-  ContractCallBase = object {.pure, inheritable.}
+  ContractCallBase {.pure, inheritable.} = object
     web3: Web3
     data: string
     to: Address
@@ -220,10 +220,10 @@ func encode*[N](x: DynamicBytes[N]): EncodeResult {.inline.} =
 func decodeDynamic(input: string, offset: int, to: var openarray[byte]): int =
   var dataOffset, dataLen: UInt256
   result = decode(input, offset, dataOffset)
-  discard decode(input, dataOffset.toInt * 2, dataLen)
+  discard decode(input, dataOffset.truncate(int) * 2, dataLen)
   # TODO: Check data len, and raise?
   let meaningfulLen = to.len * 2
-  let actualDataOffset = (dataOffset.toInt + 32) * 2
+  let actualDataOffset = (dataOffset.truncate(int) + 32) * 2
   hexToByteArray(input[actualDataOffset .. actualDataOffset + meaningfulLen - 1], to)
 
 func decode*[N](input: string, offset: int, to: var DynamicBytes[N]): int {.inline.} =
@@ -483,17 +483,17 @@ proc parseContract(body: NimNode): seq[InterfaceObject] =
     doAssert(procdef.kind == nnkProcDef,
       "Contracts can only be built with procedures")
     let
-      isconstructor = procdef[4].findChild(it.ident == !"constructor") != nil
-      isevent = procdef[4].findChild(it.ident == !"event") != nil
+      isconstructor = procdef[4].findChild(it.strVal == "constructor") != nil
+      isevent = procdef[4].findChild(it.strVal == "event") != nil
     doAssert(not (isconstructor and constructor.isSome),
       "Contract can only have a single constructor")
     doAssert(not (isconstructor and isevent),
       "Can't be both event and constructor")
     if not isevent:
       let
-        ispure = procdef[4].findChild(it.ident == !"pure") != nil
-        isview = procdef[4].findChild(it.ident == !"view") != nil
-        ispayable = procdef[4].findChild(it.ident == !"payable") != nil
+        ispure = procdef[4].findChild(it.strVal == "pure") != nil
+        isview = procdef[4].findChild(it.strVal == "view") != nil
+        ispayable = procdef[4].findChild(it.strVal == "payable") != nil
       doAssert(not (ispure and isview),
         "can't be both `pure` and `view`")
       doAssert(not ((ispure or isview) and ispayable),
@@ -506,17 +506,17 @@ proc parseContract(body: NimNode): seq[InterfaceObject] =
         ))
       else:
         functions.add FunctionObject(
-          name: $procdef[0].ident,
+          name: procdef[0].strVal,
           stateMutability: if ispure: pure elif isview: view elif ispayable: payable else: nonpayable,
           inputs: parseInputs(procdef[3]),
           outputs: parseOutputs(procdef[3][0])
         )
     else:
-      let isanonymous = procdef[4].findChild(it.ident == !"anonymous") != nil
+      let isanonymous = procdef[4].findChild(it.strVal == "anonymous") != nil
       doAssert(procdef[3][0].kind == nnkEmpty,
         "Events can't have return values")
       events.add EventObject(
-        name: $procdef[0].ident,
+        name: procdef[0].strVal,
         inputs: parseEventInputs(procdef[3]),
         anonymous: isanonymous
       )