feat: gate all logging behind logging feature flag

.github/workflows/ci.yml

@@ -75,8 +75,22 @@ jobs:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
       - uses: Swatinem/rust-cache@v2
-      - name: Build release
-        run: cargo build --release
+      - name: Build release (no logging)
+        run: cargo build --release --no-default-features
+
+  test-no-logging:
+    name: Test (no logging)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+      - uses: Swatinem/rust-cache@v2
+      - name: Install Foundry
+        uses: foundry-rs/foundry-toolchain@v1
+        with:
+          version: nightly
+      - name: Run unit tests without logging
+        run: cargo test --lib --no-default-features
 
   security:
     name: Security Audit

.github/workflows/release.yml

@@ -157,13 +157,13 @@ jobs:
         if: matrix.cross
         run: cargo install cross --git https://github.com/cross-rs/cross
 
-      - name: Build (cross)
+      - name: Build (cross, no logging)
         if: matrix.cross
-        run: cross build --release --target ${{ matrix.target }}
+        run: cross build --release --no-default-features --target ${{ matrix.target }}
 
-      - name: Build (native)
+      - name: Build (native, no logging)
         if: ${{ !matrix.cross }}
-        run: cargo build --release --target ${{ matrix.target }}
+        run: cargo build --release --no-default-features --target ${{ matrix.target }}
 
       - name: Create archive (Unix)
         if: matrix.archive == 'tar.gz'

Cargo.toml

@@ -62,10 +62,10 @@ directories = "5"
 reqwest = { version = "0.13", features = ["json", "rustls"], default-features = false }
 semver = "1"
 
-# Logging
-tracing = "0.1"
-tracing-subscriber = { version = "0.3", features = ["env-filter", "json"] }
-tracing-appender = "0.2"
+# Logging (optional — behind `logging` feature flag)
+tracing = { version = "0.1", optional = true }
+tracing-subscriber = { version = "0.3", features = ["env-filter", "json"], optional = true }
+tracing-appender = { version = "0.2", optional = true }
 
 # Error handling
 thiserror = "2"
@@ -119,7 +119,12 @@ path = "tests/e2e/mod.rs"
 required-features = ["test-utils"]
 
 [features]
-default = []
+default = ["logging"]
+# Enable tracing/logging infrastructure.
+# Included in `default` so dev builds (`cargo build`, `cargo test`) get logging
+# automatically. Release builds strip it:
+#   cargo build --release --no-default-features
+logging = ["tracing", "tracing-subscriber", "tracing-appender"]
 # Enable additional diagnostics for development
 dev = []
 # Expose test helpers (cache_insert, payment_verifier accessor) for

scripts/testnet/build-and-deploy.sh

@@ -54,8 +54,8 @@ ssh -o StrictHostKeyChecking=no "root@${BUILD_HOST}" "
         cd /root/ant-node
     fi
 
-    # Build release binary
-    cargo build --release
+    # Build release binary (no logging)
+    cargo build --release --no-default-features
 
     # Verify binary
     ls -la target/release/ant-node

scripts/testnet/testnet-endurance.sh

@@ -30,9 +30,9 @@ echo "Log file: ${LOG_FILE}" | tee -a "$LOG_FILE"
 echo "Start time: $(date)" | tee -a "$LOG_FILE"
 echo "" | tee -a "$LOG_FILE"
 
-# Build the test binary if needed
-echo "Building test binary..." | tee -a "$LOG_FILE"
-cargo build --release 2>&1 | tee -a "$LOG_FILE"
+# Build the binary (no logging)
+echo "Building binary..." | tee -a "$LOG_FILE"
+cargo build --release --no-default-features 2>&1 | tee -a "$LOG_FILE"
 
 # Export test configuration
 export ANT_TEST_BOOTSTRAP="$BOOTSTRAP"

src/bin/ant-devnet/main.rs

@@ -1,28 +1,33 @@
 //! ant-devnet CLI entry point.
 
+#![cfg_attr(not(feature = "logging"), allow(unused_variables))]
+
 mod cli;
 
 use ant_node::devnet::{Devnet, DevnetConfig, DevnetEvmInfo, DevnetManifest};
 use clap::Parser;
 use cli::Cli;
-use tracing::info;
-use tracing_subscriber::{fmt, prelude::*, EnvFilter};
 
 #[tokio::main]
 async fn main() -> color_eyre::Result<()> {
     color_eyre::install()?;
 
     let cli = Cli::parse();
 
-    let filter =
-        EnvFilter::try_from_default_env().unwrap_or_else(|_| EnvFilter::new(&cli.log_level));
+    #[cfg(feature = "logging")]
+    {
+        use tracing_subscriber::{fmt, prelude::*, EnvFilter};
+
+        let filter =
+            EnvFilter::try_from_default_env().unwrap_or_else(|_| EnvFilter::new(&cli.log_level));
 
-    tracing_subscriber::registry()
-        .with(fmt::layer())
-        .with(filter)
-        .init();
+        tracing_subscriber::registry()
+            .with(fmt::layer())
+            .with(filter)
+            .init();
+    }
 
-    info!("ant-devnet v{}", env!("CARGO_PKG_VERSION"));
+    ant_node::logging::info!("ant-devnet v{}", env!("CARGO_PKG_VERSION"));
 
     let mut config =
         cli.preset
@@ -55,7 +60,7 @@ async fn main() -> color_eyre::Result<()> {
 
     // Start Anvil and deploy contracts if EVM is enabled
     let evm_info = if cli.enable_evm {
-        info!("Starting local Anvil blockchain for EVM payment enforcement...");
+        ant_node::logging::info!("Starting local Anvil blockchain for EVM payment enforcement...");
         let testnet = evmlib::testnet::Testnet::new()
             .await
             .map_err(|e| color_eyre::eyre::eyre!("Failed to start Anvil testnet: {e}"))?;
@@ -79,8 +84,8 @@ async fn main() -> color_eyre::Result<()> {
 
         config.evm_network = Some(network);
 
-        info!("Anvil blockchain running at {rpc_url}");
-        info!("Funded wallet private key: {wallet_key}");
+        ant_node::logging::info!("Anvil blockchain running at {rpc_url}");
+        ant_node::logging::info!("Funded wallet private key: {wallet_key}");
 
         // Keep testnet alive by leaking it (it will be cleaned up on process exit)
         // This is necessary because AnvilInstance stops Anvil when dropped
@@ -111,12 +116,12 @@ async fn main() -> color_eyre::Result<()> {
     let json = serde_json::to_string_pretty(&manifest)?;
     if let Some(path) = cli.manifest {
         tokio::fs::write(&path, &json).await?;
-        info!("Wrote manifest to {}", path.display());
+        ant_node::logging::info!("Wrote manifest to {}", path.display());
     } else {
         println!("{json}");
     }
 
-    info!("Devnet running. Press Ctrl+C to stop.");
+    ant_node::logging::info!("Devnet running. Press Ctrl+C to stop.");
     tokio::signal::ctrl_c().await?;
 
     devnet.shutdown().await?;

src/bin/ant-node/cli.rs

@@ -62,21 +62,25 @@ pub struct Cli {
     pub metrics_port: u16,
 
     /// Log level.
+    #[cfg(feature = "logging")]
     #[arg(long, value_enum, default_value = "info", env = "RUST_LOG")]
     pub log_level: CliLogLevel,
 
     /// Log output format.
+    #[cfg(feature = "logging")]
     #[arg(long, value_enum, default_value = "text", env = "ANT_LOG_FORMAT")]
     pub log_format: CliLogFormat,
 
     /// Directory for log file output.
     /// When set, logs are written to files in this directory instead of stdout.
     /// Files rotate daily and are named ant-node.YYYY-MM-DD.log.
+    #[cfg(feature = "logging")]
     #[arg(long, env = "ANT_LOG_DIR")]
     pub log_dir: Option<PathBuf>,
 
     /// Maximum number of rotated log files to retain (only used with --log-dir).
     /// Oldest files are deleted when this limit is reached. Rotation is daily.
+    #[cfg(feature = "logging")]
     #[arg(long, default_value = "7", env = "ANT_LOG_MAX_FILES")]
     pub log_max_files: usize,
 
@@ -136,6 +140,7 @@ pub enum CliEvmNetwork {
 }
 
 /// Log level CLI enum.
+#[cfg(feature = "logging")]
 #[derive(Debug, Clone, Copy, ValueEnum, Default)]
 pub enum CliLogLevel {
     /// Error messages only.
@@ -152,6 +157,7 @@ pub enum CliLogLevel {
 }
 
 /// Log format CLI enum.
+#[cfg(feature = "logging")]
 #[derive(Debug, Clone, Copy, ValueEnum, Default)]
 pub enum CliLogFormat {
     /// Plain text output (default).
@@ -207,7 +213,10 @@ impl Cli {
 
         config.port = self.port;
         config.ipv4_only = self.ipv4_only;
-        config.log_level = self.log_level.into();
+        #[cfg(feature = "logging")]
+        {
+            config.log_level = self.log_level.into();
+        }
         config.network_mode = self.network_mode.into();
 
         // Apply CLI bootstrap peers if provided; otherwise keep config file value.
@@ -275,6 +284,7 @@ impl From<CliEvmNetwork> for EvmNetworkConfig {
     }
 }
 
+#[cfg(feature = "logging")]
 impl From<CliLogLevel> for String {
     fn from(level: CliLogLevel) -> Self {
         match level {