diff --git a/codex/codex.nim b/codex/codex.nim
index df1e0565..b61842c5 100644
--- a/codex/codex.nim
+++ b/codex/codex.nim
@@ -272,9 +272,7 @@ proc new*(
     engine = BlockExcEngine.new(repoStore, wallet, network, blockDiscovery, peerStore, pendingBlocks)
     store = NetworkStore.new(engine, repoStore)
     prover = if config.prover:
-      some Prover.new(
-        store,
-        config.numProofSamples)
+      some Prover.new(store, config).expect("Unable to create prover.")
     else:
       none Prover
 
diff --git a/codex/node.nim b/codex/node.nim
index de9b7461..19065c99 100644
--- a/codex/node.nim
+++ b/codex/node.nim
@@ -740,11 +740,6 @@ proc start*(self: CodexNodeRef) {.async.} =
       error "Unable to start validator contract interactions: ", error=error.msg
       self.contracts.validator = ValidatorInteractions.none
 
-  if prover =? s.codexNode.prover:
-    if err =? (await prover.start(s.config)).errorOption:
-      error "Failed to start prover", msg = err.msg
-      raise err
-
   self.networkId = self.switch.peerInfo.peerId
   notice "Started codex node", id = self.networkId, addrs = self.switch.peerInfo.addrs
 
diff --git a/codex/slots/proofs/backendfactory.nim b/codex/slots/proofs/backendfactory.nim
index 151c05f5..64bf76ef 100644
--- a/codex/slots/proofs/backendfactory.nim
+++ b/codex/slots/proofs/backendfactory.nim
@@ -5,6 +5,7 @@ import pkg/chronicles
 import pkg/questionable
 import pkg/confutils/defs
 import pkg/stew/io2
+import pkg/ethers
 
 import ../../conf
 import ./backends
@@ -65,12 +66,12 @@ proc suggestDownloadTool(config: CodexConf) =
     $address
   ]
 
-  error "Proving circuit files are not found. Please run the following to download them:" &
-    "'./" & tokens.join(" ") & "'"
+  echo "Proving circuit files are not found. Please run the following to download them:"
+  echo "'./" & tokens.join(" ") & "'"
 
 proc initializeBackend*(
   config: CodexConf,
-  utils: BackendUtils = BackendUtils()): Future[?!AnyBackend] {.async.} =
+  utils: BackendUtils = BackendUtils()): ?!AnyBackend =
 
   without backend =? initializeFromConfig(config, utils), cliErr:
     info "Could not initialize prover backend from CLI options...", msg = cliErr.msg
diff --git a/codex/slots/proofs/prover.nim b/codex/slots/proofs/prover.nim
index 6696e38b..183830ae 100644
--- a/codex/slots/proofs/prover.nim
+++ b/codex/slots/proofs/prover.nim
@@ -43,7 +43,7 @@ type
 
   AnyProofInputs* = ProofInputs[Poseidon2Hash]
   Prover* = ref object of RootObj
-    backend: ?AnyBackend
+    backend: AnyBackend
     store: BlockStore
     nSamples: int
 
@@ -62,27 +62,24 @@ proc prove*(
 
   trace "Received proof challenge"
 
-  if backend =? self.backend:
-    without builder =? AnyBuilder.new(self.store, manifest), err:
-      error "Unable to create slots builder", err = err.msg
-      return failure(err)
+  without builder =? AnyBuilder.new(self.store, manifest), err:
+    error "Unable to create slots builder", err = err.msg
+    return failure(err)
 
-    without sampler =? AnySampler.new(slotIdx, self.store, builder), err:
-      error "Unable to create data sampler", err = err.msg
-      return failure(err)
+  without sampler =? AnySampler.new(slotIdx, self.store, builder), err:
+    error "Unable to create data sampler", err = err.msg
+    return failure(err)
 
-    without proofInput =? await sampler.getProofInput(challenge, self.nSamples), err:
-      error "Unable to get proof input for slot", err = err.msg
-      return failure(err)
+  without proofInput =? await sampler.getProofInput(challenge, self.nSamples), err:
+    error "Unable to get proof input for slot", err = err.msg
+    return failure(err)
 
-    # prove slot
-    without proof =? backend.prove(proofInput), err:
-      error "Unable to prove slot", err = err.msg
-      return failure(err)
+  # prove slot
+  without proof =? self.backend.prove(proofInput), err:
+    error "Unable to prove slot", err = err.msg
+    return failure(err)
 
-    success (proofInput, proof)
-  else:
-    return failure("Prover was not started")
+  success (proofInput, proof)
 
 proc verify*(
   self: Prover,
@@ -90,29 +87,18 @@ proc verify*(
   inputs: AnyProofInputs): Future[?!bool] {.async.} =
   ## Prove a statement using backend.
   ## Returns a future that resolves to a proof.
-
-  if backend =? self.backend:
-    return backend.verify(proof, inputs)
-  else:
-    return failure("Prover was not started")
-
-proc start*(
-  self: Prover,
-  config: CodexConf): Future[?!void] {.async.} =
-
-  without backend =? (await initializeBackend(config)), err:
-    error "Failed to initialize backend", msg = err.msg
-    return failure(err)
-
-  self.backend = some backend
-  return success()
+  self.backend.verify(proof, inputs)
 
 proc new*(
   _: type Prover,
   store: BlockStore,
-  nSamples: int): Prover =
+  config: CodexConf): ?!Prover =
 
-  Prover(
+  without backend =? initializeBackend(config), err:
+    error "Failed to initialize backend", msg = err.msg
+    return failure(err)
+
+  success Prover(
     store: store,
-    backend: none AnyBackend,
-    nSamples: nSamples)
+    backend: backend,
+    nSamples: config.numProofSamples)