diff --git a/bin/node/src/main.rs b/bin/node/src/main.rs
index 5f9be712aa..ac331bc132 100644
--- a/bin/node/src/main.rs
+++ b/bin/node/src/main.rs
@@ -6,10 +6,11 @@ use aleph_runtime::Block;
 use log::warn;
 use sc_cli::{clap::Parser, CliConfiguration, PruningParams, SubstrateCli};
 use sc_network::config::Role;
-use sc_service::PartialComponents;
+use sc_service::{Configuration, PartialComponents};
 
 const STATE_PRUNING: &str = "archive";
 const BLOCKS_PRUNING: &str = "archive-canonical";
+const HEAP_PAGES: u64 = 4096;
 
 fn pruning_changed(params: &PruningParams) -> bool {
     let state_pruning_changed =
@@ -21,6 +22,12 @@ fn pruning_changed(params: &PruningParams) -> bool {
     state_pruning_changed || blocks_pruning_changed
 }
 
+// The default number of heap pages in substrate is 2048. Every heap page is 64KB,
+// so value of 4096 gives 256MB memory for entire runtime.
+fn enforce_heap_pages(config: &mut Configuration) {
+    config.default_heap_pages = Some(HEAP_PAGES);
+}
+
 fn main() -> sc_cli::Result<()> {
     let mut cli = Cli::parse();
     let overwritten_pruning = pruning_changed(&cli.run.import_params.pruning_params);
@@ -115,7 +122,7 @@ fn main() -> sc_cli::Result<()> {
         None => {
             let runner = cli.create_runner(&cli.run)?;
             if cli.aleph.experimental_pruning() {
-                warn!("Experimental_pruning was turned on. Usage of this flag can lead to misbehaviour, which can be punished. State pruning: {:?}; Blocks pruning: {:?};", 
+                warn!("Experimental_pruning was turned on. Usage of this flag can lead to misbehaviour, which can be punished. State pruning: {:?}; Blocks pruning: {:?};",
                     cli.run.state_pruning()?.unwrap_or_default(),
                     cli.run.blocks_pruning()?,
                 );
@@ -124,7 +131,9 @@ fn main() -> sc_cli::Result<()> {
             }
 
             let aleph_cli_config = cli.aleph;
-            runner.run_node_until_exit(|config| async move {
+            runner.run_node_until_exit(|mut config| async move {
+                enforce_heap_pages(&mut config);
+
                 match config.role {
                     Role::Authority => {
                         new_authority(config, aleph_cli_config).map_err(sc_cli::Error::Service)
diff --git a/bin/runtime/src/lib.rs b/bin/runtime/src/lib.rs
index 70a2f8223c..753b807773 100644
--- a/bin/runtime/src/lib.rs
+++ b/bin/runtime/src/lib.rs
@@ -106,7 +106,7 @@ pub const VERSION: RuntimeVersion = RuntimeVersion {
     spec_name: create_runtime_str!("aleph-node"),
     impl_name: create_runtime_str!("aleph-node"),
     authoring_version: 1,
-    spec_version: 52,
+    spec_version: 53,
     impl_version: 1,
     apis: RUNTIME_API_VERSIONS,
     transaction_version: 14,
@@ -681,7 +681,7 @@ impl pallet_contracts::Config for Runtime {
     type DeletionQueueDepth = DeletionQueueDepth;
     type DeletionWeightLimit = DeletionWeightLimit;
     type Schedule = Schedule;
-    type CallStack = [pallet_contracts::Frame<Self>; 31];
+    type CallStack = [pallet_contracts::Frame<Self>; 16];
     type AddressGenerator = pallet_contracts::DefaultAddressGenerator;
     type MaxCodeLen = ConstU32<{ 128 * 1024 }>;
     type MaxStorageKeyLen = ConstU32<128>;