diff --git a/ci3/parallelize_strict b/ci3/parallelize_strict
index 95e244490fa4..7683638abd8f 100755
--- a/ci3/parallelize_strict
+++ b/ci3/parallelize_strict
@@ -75,13 +75,18 @@ num_jobs=0
 
 # We'll handle errors explicitly.
 set +e
-run_tests | tee $output
+set -o pipefail
+run_tests | tee "$output"
+run_exit=$?
 
 # Loop to monitor jobs until one fails or all finish.
 while (( $(jobs -p | wc -l) > 0 )); do
   wait_for_job
 done
 
+# Propagate failure from run_tests (which runs in a subshell due to the pipe).
+[ $run_exit -ne 0 ] && exit $run_exit
+
 function filter_long_times {
   grep -E '\([0-9]+s\)$' |           # Match lines ending with (number)s
   sed 's/.*(\([0-9]\+\)s)$/\1 &/' |  # Extract number and keep original line
diff --git a/yarn-project/p2p/src/client/test/tx_proposal_collector/proposal_tx_collector_worker.ts b/yarn-project/p2p/src/client/test/tx_proposal_collector/proposal_tx_collector_worker.ts
index 44ad0f6eccc1..c756de610980 100644
--- a/yarn-project/p2p/src/client/test/tx_proposal_collector/proposal_tx_collector_worker.ts
+++ b/yarn-project/p2p/src/client/test/tx_proposal_collector/proposal_tx_collector_worker.ts
@@ -1,5 +1,4 @@
 import { MockL2BlockSource } from '@aztec/archiver/test';
-import type { EpochCache } from '@aztec/epoch-cache';
 import { SecretValue } from '@aztec/foundation/config';
 import { createLogger } from '@aztec/foundation/log';
 import { sleep } from '@aztec/foundation/sleep';
@@ -15,7 +14,6 @@ import { type TelemetryClient, getTelemetryClient } from '@aztec/telemetry-clien
 
 import type { PeerId } from '@libp2p/interface';
 import { peerIdFromString } from '@libp2p/peer-id';
-import { mock } from 'jest-mock-extended';
 
 import type { P2PConfig } from '../../../config.js';
 import { BatchTxRequesterCollector, SendBatchRequestCollector } from '../../../services/index.js';
@@ -29,6 +27,7 @@ import {
   InMemoryTxPool,
   UNLIMITED_RATE_LIMIT_QUOTA,
   calculateInternalTimeout,
+  createMockEpochCache,
   createMockWorldStateSynchronizer,
 } from '../../../test-helpers/index.js';
 import { createP2PClient } from '../../index.js';
@@ -99,7 +98,7 @@ function sendMessage(message: WorkerResponse): Promise<void> {
 async function startClient(config: P2PConfig, clientIndex: number) {
   txPool = new InMemoryTxPool();
   attestationPool = new InMemoryAttestationPool();
-  const epochCache = mock<EpochCache>();
+  const epochCache = createMockEpochCache();
   const worldState = createMockWorldStateSynchronizer();
   const l2BlockSource = new MockL2BlockSource();
   const proofVerifier = new AlwaysTrueCircuitVerifier();
diff --git a/yarn-project/p2p/src/testbench/p2p_client_testbench_worker.ts b/yarn-project/p2p/src/testbench/p2p_client_testbench_worker.ts
index 14d733793413..1d3224d94a33 100644
--- a/yarn-project/p2p/src/testbench/p2p_client_testbench_worker.ts
+++ b/yarn-project/p2p/src/testbench/p2p_client_testbench_worker.ts
@@ -4,7 +4,7 @@
  * Used when running testbench commands.
  */
 import { MockL2BlockSource } from '@aztec/archiver/test';
-import type { EpochCache, EpochCacheInterface } from '@aztec/epoch-cache';
+import type { EpochCacheInterface } from '@aztec/epoch-cache';
 import { BlockNumber } from '@aztec/foundation/branded-types';
 import { SecretValue } from '@aztec/foundation/config';
 import { Secp256k1Signer } from '@aztec/foundation/crypto/secp256k1-signer';
@@ -28,7 +28,6 @@ import { type TelemetryClient, getTelemetryClient } from '@aztec/telemetry-clien
 import type { Message, PeerId } from '@libp2p/interface';
 import { TopicValidatorResult } from '@libp2p/interface';
 import { peerIdFromString } from '@libp2p/peer-id';
-import { mock } from 'jest-mock-extended';
 
 import type { P2PClient } from '../client/index.js';
 import type { P2PConfig } from '../config.js';
@@ -50,6 +49,7 @@ import {
   InMemoryAttestationPool,
   InMemoryTxPool,
   UNLIMITED_RATE_LIMIT_QUOTA,
+  createMockEpochCache,
   createMockWorldStateSynchronizer,
   filterTxsByDistribution,
 } from '../test-helpers/index.js';
@@ -344,7 +344,7 @@ process.on('message', async msg => {
       workerConfig = config;
       workerTxPool = new InMemoryTxPool();
       workerAttestationPool = new InMemoryAttestationPool();
-      const epochCache = mock<EpochCache>();
+      const epochCache = createMockEpochCache();
       const worldState = createMockWorldStateSynchronizer();
       const l2BlockSource = new MockL2BlockSource();