diff --git a/src/config.rs b/src/config.rs
new file mode 100644
index 00000000..99ae3106
--- /dev/null
+++ b/src/config.rs
@@ -0,0 +1,76 @@
+use ethers::prelude::{Block, TxHash};
+use governor::clock::QuantaClock;
+use serde::Deserialize;
+use std::collections::{BTreeMap, HashMap};
+use std::num::NonZeroU32;
+use std::sync::Arc;
+use tokio::sync::mpsc;
+
+use crate::block_watcher::BlockWatcherSender;
+// use crate::block_watcher::BlockWatcher;
+use crate::connection::Web3Connection;
+use crate::Web3ProxyApp;
+
+#[derive(Deserialize)]
+pub struct RootConfig {
+    pub config: Web3ProxyConfig,
+    pub balanced_rpc_tiers: BTreeMap<String, HashMap<String, Web3ConnectionConfig>>,
+    pub private_rpcs: HashMap<String, Web3ConnectionConfig>,
+}
+
+#[derive(Deserialize)]
+pub struct Web3ProxyConfig {
+    pub listen_port: u16,
+}
+
+#[derive(Deserialize)]
+pub struct Web3ConnectionConfig {
+    url: String,
+    soft_limit: u32,
+    hard_limit: Option<u32>,
+}
+
+impl RootConfig {
+    pub async fn try_build(self) -> anyhow::Result<Web3ProxyApp> {
+        let balanced_rpc_tiers = self
+            .balanced_rpc_tiers
+            .into_values()
+            .map(|x| x.into_values().collect())
+            .collect();
+        let private_rpcs = self.private_rpcs.into_values().collect();
+
+        Web3ProxyApp::try_new(balanced_rpc_tiers, private_rpcs).await
+    }
+}
+
+impl Web3ConnectionConfig {
+    pub async fn try_build(
+        self,
+        clock: &QuantaClock,
+        block_watcher_sender: BlockWatcherSender,
+        http_client: Option<reqwest::Client>,
+    ) -> anyhow::Result<Arc<Web3Connection>> {
+        let hard_rate_limiter = if let Some(hard_limit) = self.hard_limit {
+            let quota = governor::Quota::per_second(NonZeroU32::new(hard_limit).unwrap());
+
+            let rate_limiter = governor::RateLimiter::direct_with_clock(quota, clock);
+
+            Some(rate_limiter)
+        } else {
+            None
+        };
+
+        Web3Connection::try_new(
+            self.url,
+            http_client,
+            block_watcher_sender,
+            hard_rate_limiter,
+            self.soft_limit,
+        )
+        .await
+    }
+
+    pub fn url(&self) -> &str {
+        &self.url
+    }
+}