diff --git a/.circleci/config.yml b/.circleci/config.yml
index ec231aba..7c0949b2 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -1,59 +1,80 @@
-#version: 2.1
-#jobs:
-#  fce:
-#    docker:
-#      - image: circleci/rust:latest
-#    environment:
-#      RUST_BACKTRACE: 1
-#      #RUST_TEST_THREADS: 1
-#    steps:
-#      - checkout
-#      - restore_cache:
-#          keys:
-#            - fce01-{{ checksum "fce/Cargo.toml" }}
-#      - run: |
-#          rustup toolchain install stable
-#          rustup component add rustfmt
-#          rustup component add clippy
-#          cd fce
-#          cargo fmt --all -- --check --color always
-#          cargo build -v --all-features
-#          cargo test -v --all-features
-#          cargo clippy -v
-#      - save_cache:
-#          paths:
-#            - ~/.cargo
-#            - ~/.rustup
-#          key: fce01-{{ checksum "fce/Cargo.toml" }}
-#  wit_embedder:
-#    docker:
-#      - image: circleci/rust:latest
-#    environment:
-#      RUST_BACKTRACE: 1
-#      #RUST_TEST_THREADS: 1
-#    steps:
-#      - checkout
-#      - restore_cache:
-#          keys:
-#            - wit_embedder01-{{ checksum "wit_embedder/Cargo.toml" }}
-#      - run: |
-#          rustup toolchain install stable
-#          rustup component add rustfmt
-#          rustup component add clippy
-#          cd wit_embedder
-#          cargo fmt --all -- --check --color always
-#          cargo build -v --all-features
-#          cargo test -v --all-features
-#          cargo clippy -v
-#      - save_cache:
-#          paths:
-#            - ~/.cargo
-#            - ~/.rustup
-#          key: wit_embedder01-{{ checksum "wit_embedder/Cargo.toml" }}
-#
-#workflows:
-#  version: 2.1
-#  fce:
-#    jobs:
-#      - fce
-#      - wit_embedder
+version: 2.1
+jobs:
+  fce:
+    docker:
+      - image: circleci/rust:latest
+    environment:
+      RUST_BACKTRACE: 1
+      #RUST_TEST_THREADS: 1
+    steps:
+      - checkout
+      - restore_cache:
+          keys:
+            - fce01-{{ checksum "engine/Cargo.toml" }}-{{ checksum "fluence-faas/Cargo.toml" }}
+      - run: |
+          rustup toolchain install nightly
+          rustup component add rustfmt
+          rustup component add clippy --toolchain nightly
+
+          cd engine
+          cargo fmt --all -- --check --color always
+          cargo +nightly build -v --all-features
+          cargo +nightly test -v --all-features
+          cargo +nightly clippy -v
+
+          cd ../fluence-faas
+          cargo fmt --all -- --check --color always
+          cargo +nightly build -v --all-features
+          cargo +nightly test -v --all-features
+          cargo +nightly clippy -v
+
+      - save_cache:
+          paths:
+            - ~/.cargo
+            - ~/.rustup
+          key: fce01-{{ checksum "engine/Cargo.toml" }}-{{ checksum "fluence-faas/Cargo.toml" }}
+
+  examples:
+    docker:
+      - image: circleci/rust:latest
+    environment:
+      RUST_BACKTRACE: 1
+      #RUST_TEST_THREADS: 1
+    steps:
+      - checkout
+      - restore_cache:
+          keys:
+            - examples01-{{ checksum "examples/ipfs_node/wasm/ipfs_node/Cargo.toml" }}-{{ checksum "examples/ipfs_node/wasm/ipfs_rpc/Cargo.toml" }}-{{ checksum "examples/ipfs_node/Cargo.toml" }}
+      - run: |
+          rustup toolchain install nightly
+          rustup component add rustfmt
+          rustup component add clippy
+          cargo install cargo-wasi
+
+          cd examples/ipfs_node/wasm/ipfs_node
+          cargo fmt --all -- --check --color always
+          cargo wasi build
+          cargo clippy -v
+
+          cd ../ipfs_rpc
+          cargo fmt --all -- --check --color always
+          cargo wasi build
+          cargo clippy -v
+
+          cd ../../../../tools/wit_embedder
+          cargo fmt --all -- --check --color always
+          cargo build -v --all-features
+          cargo clippy -v
+
+      - save_cache:
+          paths:
+            - ~/.cargo
+            - ~/.rustup
+          key: examples01-{{ checksum "examples/ipfs_node/wasm/ipfs_node/Cargo.toml" }}-{{ checksum "examples/ipfs_node/wasm/ipfs_rpc/Cargo.toml" }}-{{ checksum "examples/ipfs_node/Cargo.toml" }}
+
+workflows:
+  version: 2.1
+  fce:
+    jobs:
+      - fce
+      - examples
diff --git a/.gitignore b/.gitignore
index 18bc1ef6..b2e56494 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,6 +6,9 @@ target/
 *.wasm
 *.wat
 
-# Allowed Wasm files for the example
+# Temporary file of ipfs node example
+/examples/ipfs_node/wasm/artifacts/ipfs_rpc_file
+
+# Allowed Wasm files for examples
 !/examples/ipfs_node/wasm/artifacts/wasm_ipfs_rpc_wit.wasi.wasm
 !/examples/ipfs_node/wasm/artifacts/wasm_modules/*
diff --git a/examples/ipfs_node/src/main.rs b/examples/ipfs_node/src/main.rs
index 2186db61..865d78e3 100644
--- a/examples/ipfs_node/src/main.rs
+++ b/examples/ipfs_node/src/main.rs
@@ -41,7 +41,11 @@ fn main() {
     println!("ipfs node addresses are:\n{:?}", node_addresses);
 
     let result = ipfs_node
-        .call_code(&ipfs_rpc, "put", &[IValue::String("Hello, world".to_string())])
+        .call_code(
+            &ipfs_rpc,
+            "put",
+            &[IValue::String("Hello, world".to_string())],
+        )
         .unwrap();
 
     println!("execution result {:?}", result);
diff --git a/examples/ipfs_node/wasm/ipfs_node/src/main.rs b/examples/ipfs_node/wasm/ipfs_node/src/main.rs
index 12909952..5d10124b 100644
--- a/examples/ipfs_node/wasm/ipfs_node/src/main.rs
+++ b/examples/ipfs_node/wasm/ipfs_node/src/main.rs
@@ -26,11 +26,10 @@ use crate::path::to_full_path;
 const RESULT_FILE_PATH: &str = "/tmp/ipfs_rpc_file";
 
 pub fn main() {
-    let env_variable = std::env::var("tmp").unwrap();
-    println!(
-        "ipfs_node.main: WASI initialization finished, env {}",
-        env_variable
-    );
+    let msg = "ipfs_node.main: WASI initialization finished, env {}";
+    unsafe {
+        log_utf8_string(msg.as_ptr() as _, msg.len() as _);
+    }
 }
 
 #[no_mangle]
diff --git a/examples/ipfs_node/wasm/ipfs_rpc/src/main.rs b/examples/ipfs_node/wasm/ipfs_rpc/src/main.rs
index 45727fb2..245fee8c 100644
--- a/examples/ipfs_node/wasm/ipfs_rpc/src/main.rs
+++ b/examples/ipfs_node/wasm/ipfs_rpc/src/main.rs
@@ -25,7 +25,10 @@ use std::path::PathBuf;
 const RPC_TMP_FILEPATH: &str = "/tmp/ipfs_rpc_file";
 
 pub fn main() {
-    println!("ipfs_rpc.main: WASI initialization finished");
+    let msg = "ipfs_rpc.main: WASI initialization finished, env {}";
+    unsafe {
+        log_utf8_string(msg.as_ptr() as _, msg.len() as _);
+    }
 }
 
 #[no_mangle]
diff --git a/fluence-faas/src/errors.rs b/fluence-faas/src/errors.rs
index 42e5cb31..d65ac5bb 100644
--- a/fluence-faas/src/errors.rs
+++ b/fluence-faas/src/errors.rs
@@ -27,7 +27,7 @@ pub enum FaaSError {
     /// Various errors related to file i/o.
     IOError(String),
 
-    /// WIT doesn't contain such type.
+    /// FCE errors.
     EngineError(FCEError),
 }
 
diff --git a/fluence-faas/src/misc/utils.rs b/fluence-faas/src/misc/utils.rs
index 75de46ca..bf03c36f 100644
--- a/fluence-faas/src/misc/utils.rs
+++ b/fluence-faas/src/misc/utils.rs
@@ -103,9 +103,7 @@ where
 }
 
 /// Make FCE config based on parsed raw config.
-pub(crate) fn make_fce_config(
-    config: Option<ModuleConfig>,
-) -> Result<FCEModuleConfig, FaaSError> {
+pub(crate) fn make_fce_config(config: Option<ModuleConfig>) -> Result<FCEModuleConfig, FaaSError> {
     use super::imports::create_host_import_func;
     use super::imports::log_utf8_string;
     use wasmer_core::import::Namespace;