diff --git a/khbb_lib/Cargo.toml b/khbb_lib/Cargo.toml
index 5a8b868..9eff49b 100644
--- a/khbb_lib/Cargo.toml
+++ b/khbb_lib/Cargo.toml
@@ -38,3 +38,4 @@ tracing.workspace = true
 tracing-subscriber.workspace = true
 yellowstone-grpc-client.workspace = true
 yellowstone-grpc-proto.workspace = true
+uuid.workspace = true
diff --git a/khbb_lib/src/config.rs b/khbb_lib/src/config.rs
index 335ed27..b4b06e7 100644
--- a/khbb_lib/src/config.rs
+++ b/khbb_lib/src/config.rs
@@ -83,3 +83,98 @@ impl KhbbAppConfig {
         Ok(())
     }
 }
+
+#[cfg(test)]
+mod tests {
+    fn build_valid_config() -> crate::KhbbAppConfig {
+        crate::KhbbAppConfig {
+            database_url: std::string::String::from("sqlite://./dbdata/app.db"),
+            solana_http_rpc_url: std::string::String::from(
+                "https://mainnet.helius-rpc.com/?api-key=test",
+            ),
+            solana_ws_rpc_url: std::string::String::from(
+                "wss://mainnet.helius-rpc.com/?api-key=test",
+            ),
+            yellowstone_grpc_url: Some(std::string::String::from(
+                "https://mainnet.helius-rpc.com:443",
+            )),
+            log_filter: std::string::String::from("info"),
+            bootstrap_database: true,
+            listener_poll_interval_ms: 1000,
+        }
+    }
+
+    #[test]
+    fn validate_accepts_valid_config() {
+        let config = build_valid_config();
+        let result = config.validate();
+        assert!(result.is_ok());
+    }
+
+    #[test]
+    fn validate_rejects_empty_database_url() {
+        let mut config = build_valid_config();
+        config.database_url = std::string::String::new();
+        let result = config.validate();
+        assert!(result.is_err());
+    }
+
+    #[test]
+    fn validate_rejects_empty_http_rpc_url() {
+        let mut config = build_valid_config();
+        config.solana_http_rpc_url = std::string::String::new();
+        let result = config.validate();
+        assert!(result.is_err());
+    }
+
+    #[test]
+    fn validate_rejects_empty_ws_rpc_url() {
+        let mut config = build_valid_config();
+        config.solana_ws_rpc_url = std::string::String::new();
+        let result = config.validate();
+        assert!(result.is_err());
+    }
+
+    #[test]
+    fn validate_rejects_empty_log_filter() {
+        let mut config = build_valid_config();
+        config.log_filter = std::string::String::new();
+        let result = config.validate();
+        assert!(result.is_err());
+    }
+
+    #[test]
+    fn validate_rejects_zero_poll_interval() {
+        let mut config = build_valid_config();
+        config.listener_poll_interval_ms = 0;
+        let result = config.validate();
+        assert!(result.is_err());
+    }
+
+    #[tokio::test]
+    async fn load_from_json_file_loads_valid_json() {
+        let temp_dir =
+            std::env::temp_dir().join(std::format!("khbb_config_test_{}", uuid::Uuid::new_v4()));
+        std::fs::create_dir_all(&temp_dir).expect("create temp dir");
+        let config_path = temp_dir.join("config.json");
+
+        let config_json = r#"{
+  "database_url": "sqlite://./dbdata/app.db",
+  "solana_http_rpc_url": "https://mainnet.helius-rpc.com/?api-key=test",
+  "solana_ws_rpc_url": "wss://mainnet.helius-rpc.com/?api-key=test",
+  "yellowstone_grpc_url": "https://mainnet.helius-rpc.com:443",
+  "log_filter": "info",
+  "bootstrap_database": true,
+  "listener_poll_interval_ms": 1000
+}"#;
+
+        std::fs::write(&config_path, config_json).expect("write config file");
+        let result = crate::KhbbAppConfig::load_from_json_file(
+            config_path.to_str().expect("config path to str"),
+        )
+        .await;
+        assert!(result.is_ok());
+        let _ = std::fs::remove_file(&config_path);
+        let _ = std::fs::remove_dir_all(&temp_dir);
+    }
+}
diff --git a/khbb_lib/src/storage.rs b/khbb_lib/src/storage.rs
index 47b82b1..52a13f8 100644
--- a/khbb_lib/src/storage.rs
+++ b/khbb_lib/src/storage.rs
@@ -2,47 +2,59 @@
 
 //! SQLite storage bootstrap and persistence helpers.
 
+fn extract_sqlite_file_path(
+    database_url: &str,
+) -> core::result::Result<std::option::Option<std::path::PathBuf>, crate::KhbbError> {
+    if database_url == "sqlite::memory:" {
+        return Ok(None);
+    }
+    if let Some(value) = database_url.strip_prefix("sqlite://") {
+        return Ok(Some(std::path::PathBuf::from(value)));
+    }
+    if let Some(value) = database_url.strip_prefix("sqlite:") {
+        return Ok(Some(std::path::PathBuf::from(value)));
+    }
+    Err(crate::KhbbError::Config {
+        message: std::format!("invalid sqlite database url `{database_url}`"),
+    })
+}
+
 /// Creates a SQLite pool for the khbb runtime.
 pub async fn create_sqlite_pool(
     database_url: &str,
 ) -> core::result::Result<sqlx::SqlitePool, crate::KhbbError> {
-    let sqlite_path = if let Some(value) = database_url.strip_prefix("sqlite://") {
-        value
-    } else if let Some(value) = database_url.strip_prefix("sqlite:") {
-        value
-    } else {
-        ""
+    let sqlite_path_result = extract_sqlite_file_path(database_url);
+    let sqlite_path = match sqlite_path_result {
+        Ok(value) => value,
+        Err(error) => {
+            return Err(error);
+        },
     };
-    if !sqlite_path.is_empty() {
-        let path = std::path::Path::new(sqlite_path);
+    if let Some(path) = sqlite_path {
         if let Some(parent) = path.parent() {
             if !parent.as_os_str().is_empty() {
                 let create_dir_result = tokio::fs::create_dir_all(parent).await;
                 match create_dir_result {
-                    Ok(()) => {}
+                    Ok(()) => {},
                     Err(error) => {
                         return Err(crate::KhbbError::Io {
                             context: "create sqlite parent directory",
                             message: error.to_string(),
                         });
-                    }
+                    },
                 }
             }
         }
     }
-    let parse_result = <sqlx::sqlite::SqliteConnectOptions as std::str::FromStr>::from_str(
-        database_url,
-    );
+    let parse_result =
+        <sqlx::sqlite::SqliteConnectOptions as std::str::FromStr>::from_str(database_url);
     let connect_options = match parse_result {
         Ok(value) => value.create_if_missing(true),
         Err(error) => {
             return Err(crate::KhbbError::Config {
-                message: std::format!(
-                    "invalid sqlite database url `{database_url}`: {}",
-                    error
-                ),
+                message: std::format!("invalid sqlite database url `{database_url}`: {}", error),
             });
-        }
+        },
     };
     let connect_result = sqlx::sqlite::SqlitePoolOptions::new()
         .max_connections(1)
@@ -266,3 +278,130 @@ WHERE id = ?2;
         }),
     }
 }
+
+#[cfg(test)]
+mod tests {
+    fn build_test_config(database_url: std::string::String) -> crate::KhbbAppConfig {
+        crate::KhbbAppConfig {
+            database_url,
+            solana_http_rpc_url: std::string::String::from(
+                "https://mainnet.helius-rpc.com/?api-key=test",
+            ),
+            solana_ws_rpc_url: std::string::String::from(
+                "wss://mainnet.helius-rpc.com/?api-key=test",
+            ),
+            yellowstone_grpc_url: Some(std::string::String::from(
+                "https://mainnet.helius-rpc.com:443",
+            )),
+            log_filter: std::string::String::from("info"),
+            bootstrap_database: true,
+            listener_poll_interval_ms: 1000,
+        }
+    }
+
+    fn build_temp_sqlite_url() -> std::string::String {
+        let temp_dir =
+            std::env::temp_dir().join(std::format!("khbb_storage_test_{}", uuid::Uuid::new_v4()));
+        let db_path = temp_dir.join("app.db");
+        std::format!("sqlite://{}", db_path.to_string_lossy())
+    }
+
+    #[test]
+    fn extract_sqlite_file_path_accepts_memory_url() {
+        let result = super::extract_sqlite_file_path("sqlite::memory:");
+        assert!(result.is_ok());
+        let path = result.expect("extract memory path");
+        assert!(path.is_none());
+    }
+
+    #[test]
+    fn extract_sqlite_file_path_accepts_file_url() {
+        let result = super::extract_sqlite_file_path("sqlite://./dbdata/app.db");
+        assert!(result.is_ok());
+        let path = result.expect("extract file path");
+        assert!(path.is_some());
+    }
+
+    #[test]
+    fn extract_sqlite_file_path_rejects_invalid_scheme() {
+        let result = super::extract_sqlite_file_path("postgres://localhost/test");
+        assert!(result.is_err());
+    }
+
+    #[tokio::test]
+    async fn create_sqlite_pool_creates_file_database() {
+        let database_url = build_temp_sqlite_url();
+        let pool_result = crate::create_sqlite_pool(&database_url).await;
+        assert!(pool_result.is_ok());
+        let pool = pool_result.expect("create sqlite pool");
+        let ping_result = sqlx::query("SELECT 1;").execute(&pool).await;
+        assert!(ping_result.is_ok());
+    }
+
+    #[tokio::test]
+    async fn ensure_sqlite_schema_creates_tables() {
+        let database_url = build_temp_sqlite_url();
+        let pool_result = crate::create_sqlite_pool(&database_url).await;
+        assert!(pool_result.is_ok());
+        let pool = pool_result.expect("create sqlite pool");
+        let schema_result = crate::ensure_sqlite_schema(&pool).await;
+        assert!(schema_result.is_ok());
+        let query_result = sqlx::query(
+            r#"
+SELECT name
+FROM sqlite_master
+WHERE type = 'table'
+  AND name = 'listener_sessions';
+"#,
+        )
+        .fetch_one(&pool)
+        .await;
+        assert!(query_result.is_ok());
+    }
+
+    #[tokio::test]
+    async fn insert_listener_session_inserts_row() {
+        let database_url = build_temp_sqlite_url();
+        let pool_result = crate::create_sqlite_pool(&database_url).await;
+        assert!(pool_result.is_ok());
+        let pool = pool_result.expect("create sqlite pool");
+        let schema_result = crate::ensure_sqlite_schema(&pool).await;
+        assert!(schema_result.is_ok());
+        let config = build_test_config(database_url);
+        let insert_result = super::insert_listener_session(&pool, &config).await;
+        assert!(insert_result.is_ok());
+        let session = insert_result.expect("insert listener session");
+        assert!(session.id > 0);
+        assert_eq!(session.status, "running");
+    }
+
+    #[tokio::test]
+    async fn update_listener_session_status_updates_row() {
+        let database_url = build_temp_sqlite_url();
+        let pool_result = crate::create_sqlite_pool(&database_url).await;
+        assert!(pool_result.is_ok());
+        let pool = pool_result.expect("create sqlite pool");
+        let schema_result = crate::ensure_sqlite_schema(&pool).await;
+        assert!(schema_result.is_ok());
+        let config = build_test_config(database_url);
+        let insert_result = super::insert_listener_session(&pool, &config).await;
+        assert!(insert_result.is_ok());
+        let session = insert_result.expect("insert listener session");
+        let update_result =
+            super::update_listener_session_status(&pool, session.id, "stopped").await;
+        assert!(update_result.is_ok());
+        let fetch_result = sqlx::query_scalar::<_, std::string::String>(
+            r#"
+SELECT status
+FROM listener_sessions
+WHERE id = ?1;
+"#,
+        )
+        .bind(session.id)
+        .fetch_one(&pool)
+        .await;
+        assert!(fetch_result.is_ok());
+        let status = fetch_result.expect("fetch updated status");
+        assert_eq!(status, "stopped");
+    }
+}