diff --git a/research/stack_sizes.nim b/research/stack_sizes.nim
index c77bdbe82..aaeffea6b 100644
--- a/research/stack_sizes.nim
+++ b/research/stack_sizes.nim
@@ -5,12 +5,18 @@
 #   * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
+{.push raises: [].}
+
 import ../beacon_chain/spec/datatypes/phase0
 
 import std/[typetraits, strformat, strutils]
 
 proc print(t: auto, n: string, indent: int) =
-  echo fmt"{sizeof(t):>8}  {spaces(indent)}{n}: {typeof(t).name}"
+  try:
+    echo fmt"{sizeof(t):>8}  {spaces(indent)}{n}: {typeof(t).name}"
+  except ValueError:
+    # https://github.com/nim-lang/Nim/pull/23356
+    raiseAssert "Arguments match the format string"
 
   when t is object|tuple:
     for n, p in t.fieldPairs:
diff --git a/tests/test_discovery.nim b/tests/test_discovery.nim
index 3c7957773..f33ed569a 100644
--- a/tests/test_discovery.nim
+++ b/tests/test_discovery.nim
@@ -5,6 +5,7 @@
 #   * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
+{.push raises: [].}
 {.used.}
 
 import
@@ -19,14 +20,17 @@ proc new(T: type Eth2DiscoveryProtocol,
     enrIp: Option[IpAddress], enrTcpPort, enrUdpPort: Option[Port],
     bindPort: Port, bindIp: IpAddress,
     enrFields: openArray[(string, seq[byte])] = [],
-    rng: ref HmacDrbgContext):
-    T {.raises: [CatchableError].} =
+    rng: ref HmacDrbgContext): T =
   newProtocol(pk, enrIp, enrTcpPort, enrUdpPort, enrFields,
     bindPort = bindPort, bindIp = bindIp, rng = rng)
 
 proc generateNode(rng: ref HmacDrbgContext, port: Port,
     enrFields: openArray[(string, seq[byte])] = []): Eth2DiscoveryProtocol =
-  let ip = parseIpAddress("127.0.0.1")
+  let ip =
+    try:
+      parseIpAddress("127.0.0.1")
+    except ValueError:
+      raiseAssert "Argument is a valid IP address"
   Eth2DiscoveryProtocol.new(keys.PrivateKey.random(rng[]),
         some(ip), some(port), some(port), port, ip, enrFields, rng = rng)
 
diff --git a/tests/test_signing_node.nim b/tests/test_signing_node.nim
index 7e36e3d4f..909d1e929 100644
--- a/tests/test_signing_node.nim
+++ b/tests/test_signing_node.nim
@@ -1,10 +1,12 @@
-# nimbus_signing_node
+# beacon_chain
 # Copyright (c) 2023-2024 Status Research & Development GmbH
 # Licensed and distributed under either of
 #   * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
 #   * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
+{.push raises: [].}
+
 import
   std/algorithm,
   unittest2, chronicles, stew/[results, byteutils, io2],
@@ -17,8 +19,6 @@ import
 
 from std/os import getEnv, osErrorMsg
 
-{.push raises: [].}
-{.pop.}    # TODO want actual revert, so placate linter
 {.used.}
 
 const
@@ -100,20 +100,25 @@ func init(T: type ForkedBeaconBlock, contents: ProduceBlockResponseV2): T =
   of ConsensusFork.Deneb:
     return ForkedBeaconBlock.init(contents.denebData.`block`)
 
-proc getBlock(fork: ConsensusFork,
-              feeRecipient = SigningExpectedFeeRecipient): ForkedBeaconBlock =
+proc getBlock(
+    fork: ConsensusFork,
+    feeRecipient = SigningExpectedFeeRecipient
+): ForkedBeaconBlock {.raises: [ResultError[cstring]].} =
   let
     blckData =
-      case fork
-      of ConsensusFork.Phase0:    Phase0Block
-      of ConsensusFork.Altair:    AltairBlock
-      of ConsensusFork.Bellatrix: BellatrixBlock % [feeRecipient]
-      of ConsensusFork.Capella:   CapellaBlock % [feeRecipient]
-      of ConsensusFork.Deneb:     DenebBlockContents % [feeRecipient]
+      try:
+        case fork
+        of ConsensusFork.Phase0:    Phase0Block
+        of ConsensusFork.Altair:    AltairBlock
+        of ConsensusFork.Bellatrix: BellatrixBlock % [feeRecipient]
+        of ConsensusFork.Capella:   CapellaBlock % [feeRecipient]
+        of ConsensusFork.Deneb:     DenebBlockContents % [feeRecipient]
+      except ValueError:
+        # https://github.com/nim-lang/Nim/pull/23356
+        raiseAssert "Arguments match the format string"
     contentType = ContentTypeData(
       mediaType: MediaType.init("application/json"))
 
-
   let b = decodeBytes(ProduceBlockResponseV2,
                       blckData.toOpenArrayByte(0, len(blckData) - 1),
                       Opt.some(contentType),