diff --git a/Cargo.lock b/Cargo.lock
index ddb43149..43b45c2f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1386,6 +1386,9 @@ dependencies = [
 [[package]]
 name = "entities"
 version = "0.1.0"
+dependencies = [
+ "sea-orm",
+]
 
 [[package]]
 name = "eth-keystore"
diff --git a/README.md b/README.md
index 7c87e47d..dc6388e8 100644
--- a/README.md
+++ b/README.md
@@ -59,6 +59,14 @@ $ websocat ws://127.0.0.1:8544
 
 You can copy `config/example.toml` to `config/production-$CHAINNAME.toml` and then run `docker-compose up --build -d` start proxies for many chains.
 
+## Database entities
+
+Types for database entities are generated from a development database.
+
+```
+sea-orm-cli generate entity -u mysql://root:dev_web3_proxy@127.0.0.1:3306/dev_web3_proxy -o entities/src
+```
+
 ## Flame Graphs
 
 Flame graphs make finding slow code painless:
diff --git a/entities/Cargo.toml b/entities/Cargo.toml
index f9763dd4..65563b06 100644
--- a/entities/Cargo.toml
+++ b/entities/Cargo.toml
@@ -3,6 +3,11 @@ name = "entities"
 version = "0.1.0"
 edition = "2021"
 
+[lib]
+name = "entities"
+path = "src/mod.rs"
+
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+sea-orm = { version = "0.9.1" }
diff --git a/entities/src/block_list.rs b/entities/src/block_list.rs
index 203f3aec..cbe82db3 100644
--- a/entities/src/block_list.rs
+++ b/entities/src/block_list.rs
@@ -7,8 +7,8 @@ use sea_orm::entity::prelude::*;
 pub struct Model {
     #[sea_orm(primary_key)]
     pub id: i64,
+    #[sea_orm(unique)]
     pub address: String,
-    pub chain: i32,
     pub description: String,
 }
 
diff --git a/entities/src/user.rs b/entities/src/user.rs
index 64b50fe0..b75bf964 100644
--- a/entities/src/user.rs
+++ b/entities/src/user.rs
@@ -10,7 +10,7 @@ pub struct Model {
     #[sea_orm(unique)]
     pub address: String,
     pub description: String,
-    pub email: String,
+    pub email: Option<String>,
 }
 
 #[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
diff --git a/entities/src/user_keys.rs b/entities/src/user_keys.rs
index 2df86a89..660e88fa 100644
--- a/entities/src/user_keys.rs
+++ b/entities/src/user_keys.rs
@@ -8,6 +8,7 @@ pub struct Model {
     #[sea_orm(primary_key)]
     pub id: i64,
     pub user_id: i64,
+    #[sea_orm(unique)]
     pub api_key: String,
     pub description: String,
     pub private_txs: i8,
diff --git a/migration/src/m20220101_000001_create_table.rs b/migration/src/m20220101_000001_create_table.rs
index 3448c9c3..fcdaf83f 100644
--- a/migration/src/m20220101_000001_create_table.rs
+++ b/migration/src/m20220101_000001_create_table.rs
@@ -25,7 +25,7 @@ impl MigrationTrait for Migration {
                             .unique_key(),
                     )
                     .col(ColumnDef::new(User::Description).string().not_null())
-                    .col(ColumnDef::new(User::Email).string().not_null())
+                    .col(ColumnDef::new(User::Email).string())
                     .to_owned(),
             )
             .await?;
diff --git a/web3-proxy/src/app.rs b/web3-proxy/src/app.rs
index bf5a46ce..138bc26f 100644
--- a/web3-proxy/src/app.rs
+++ b/web3-proxy/src/app.rs
@@ -465,7 +465,7 @@ impl Web3ProxyApp {
 
         // TODO: this only needs to be unique per connection. we don't need it globably unique
         let subscription_id = subscription_count.fetch_add(1, atomic::Ordering::SeqCst);
-        let subscription_id = format!("{:#x}", subscription_id);
+        let subscription_id = U64::from(subscription_id);
 
         // save the id so we can use it in the response
         let id = payload.id.clone();
@@ -476,8 +476,6 @@ impl Web3ProxyApp {
             Some(x) if x == json!(["newHeads"]) => {
                 let head_block_receiver = self.head_block_receiver.clone();
 
-                let subscription_id = subscription_id.clone();
-
                 trace!(?subscription_id, "new heads subscription");
                 tokio::spawn(async move {
                     let mut head_block_receiver = Abortable::new(
@@ -510,8 +508,6 @@ impl Web3ProxyApp {
             Some(x) if x == json!(["newPendingTransactions"]) => {
                 let pending_tx_receiver = self.pending_tx_sender.subscribe();
 
-                let subscription_id = subscription_id.clone();
-
                 let mut pending_tx_receiver = Abortable::new(
                     BroadcastStream::new(pending_tx_receiver),
                     subscription_registration,
@@ -551,8 +547,6 @@ impl Web3ProxyApp {
                 // TODO: too much copy/pasta with newPendingTransactions
                 let pending_tx_receiver = self.pending_tx_sender.subscribe();
 
-                let subscription_id = subscription_id.clone();
-
                 let mut pending_tx_receiver = Abortable::new(
                     BroadcastStream::new(pending_tx_receiver),
                     subscription_registration,
@@ -600,8 +594,6 @@ impl Web3ProxyApp {
                     subscription_registration,
                 );
 
-                let subscription_id = subscription_id.clone();
-
                 trace!(?subscription_id, "pending transactions subscription");
 
                 // TODO: do something with this handle?
diff --git a/web3-proxy/src/frontend/users.rs b/web3-proxy/src/frontend/users.rs
index 339ba502..c80769ea 100644
--- a/web3-proxy/src/frontend/users.rs
+++ b/web3-proxy/src/frontend/users.rs
@@ -11,6 +11,10 @@ use axum::{http::StatusCode, response::IntoResponse, Json};
 use ethers::prelude::{Address, Bytes};
 use serde::{Deserialize, Serialize};
 
+use entities::user;
+
+// use entities::user::User;
+
 pub async fn create_user(
     // this argument tells axum to parse the request body
     // as JSON into a `CreateUser` type
@@ -18,28 +22,26 @@ pub async fn create_user(
 ) -> impl IntoResponse {
     // TODO: rate limit by ip
     // TODO: insert your application logic here
-    let user = User {
-        id: 1337,
-        eth_address: payload.eth_address,
+    let user = user::ActiveModel {
+        address: sea_orm::Set(payload.address.to_string()),
+        ..Default::default()
     };
 
+    // TODO: optional email
+
+    todo!();
+
     // this will be converted into a JSON response
     // with a status code of `201 Created`
-    (StatusCode::CREATED, Json(user))
+    // (StatusCode::CREATED, Json(user))
 }
 
 // the input to our `create_user` handler
 #[derive(Deserialize)]
 pub struct CreateUser {
-    eth_address: Address,
-    // TODO: validation
+    address: Address,
+    // TODO: make sure the email address is valid
     email: Option<String>,
     signature: Bytes,
-}
-
-// the output to our `create_user` handler
-#[derive(Serialize)]
-struct User {
-    id: u64,
-    eth_address: Address,
+    invite_code: String,
 }
diff --git a/web3-proxy/src/jsonrpc.rs b/web3-proxy/src/jsonrpc.rs
index 4ae5d9dc..dc81963e 100644
--- a/web3-proxy/src/jsonrpc.rs
+++ b/web3-proxy/src/jsonrpc.rs
@@ -168,7 +168,6 @@ impl JsonRpcForwardedResponse {
 
         JsonRpcForwardedResponse {
             jsonrpc: "2.0".to_string(),
-            // TODO: what id can we use? how do we make sure the incoming id gets attached to this?
             id,
             result: None,
             error: Some(JsonRpcErrorData {