diff --git a/Cargo.lock b/Cargo.lock
index 3084e9b01af..e6285fbb408 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -569,16 +569,6 @@ dependencies = [
  "serde",
 ]
 
-[[package]]
-name = "buf_redux"
-version = "0.8.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b953a6887648bb07a535631f2bc00fbdb2a2216f135552cb3f534ed136b9c07f"
-dependencies = [
- "memchr",
- "safemem",
-]
-
 [[package]]
 name = "bumpalo"
 version = "3.4.0"
@@ -750,7 +740,6 @@ dependencies = [
  "eth2_ssz",
  "futures 0.3.5",
  "genesis",
- "http_api",
  "lazy_static",
  "lighthouse_metrics",
  "network",
@@ -2136,31 +2125,6 @@ dependencies = [
  "tokio 0.2.22",
 ]
 
-[[package]]
-name = "headers"
-version = "0.3.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ed18eb2459bf1a09ad2d6b1547840c3e5e62882fa09b9a6a20b1de8e3228848f"
-dependencies = [
- "base64 0.12.3",
- "bitflags 1.2.1",
- "bytes 0.5.6",
- "headers-core",
- "http 0.2.1",
- "mime 0.3.16",
- "sha-1",
- "time 0.1.43",
-]
-
-[[package]]
-name = "headers-core"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e7f66481bfee273957b1f20485a4ff3362987f85b2c236580d81b4eb7a326429"
-dependencies = [
- "http 0.2.1",
-]
-
 [[package]]
 name = "heck"
 version = "0.3.1"
@@ -2282,19 +2246,6 @@ dependencies = [
  "http 0.2.1",
 ]
 
-[[package]]
-name = "http_api"
-version = "0.1.0"
-dependencies = [
- "beacon_chain",
- "hex 0.4.2",
- "parking_lot 0.11.0",
- "serde",
- "tokio 0.2.22",
- "types",
- "warp",
-]
-
 [[package]]
 name = "httparse"
 version = "1.3.4"
@@ -2468,15 +2419,6 @@ dependencies = [
  "hashbrown 0.8.2",
 ]
 
-[[package]]
-name = "input_buffer"
-version = "0.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "19a8a95243d5a0398cae618ec29477c6e3cb631152be5c19481f80bc71559754"
-dependencies = [
- "bytes 0.5.6",
-]
-
 [[package]]
 name = "instant"
 version = "0.1.6"
@@ -3162,18 +3104,6 @@ version = "0.3.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2a60c7ce501c71e03a9c9c0d35b861413ae925bd979cc7a4e30d060069aaac8d"
 
-[[package]]
-name = "mime_guess"
-version = "1.8.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "216929a5ee4dd316b1702eedf5e74548c123d370f47841ceaac38ca154690ca3"
-dependencies = [
- "mime 0.2.6",
- "phf",
- "phf_codegen",
- "unicase 1.4.2",
-]
-
 [[package]]
 name = "mime_guess"
 version = "2.0.3"
@@ -3290,24 +3220,6 @@ version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1255076139a83bb467426e7f8d0134968a8118844faa755985e077cf31850333"
 
-[[package]]
-name = "multipart"
-version = "0.16.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "136eed74cadb9edd2651ffba732b19a450316b680e4f48d6c79e905799e19d01"
-dependencies = [
- "buf_redux",
- "httparse",
- "log 0.4.11",
- "mime 0.2.6",
- "mime_guess 1.8.8",
- "quick-error 1.2.3",
- "rand 0.6.5",
- "safemem",
- "tempfile",
- "twoway",
-]
-
 [[package]]
 name = "multistream-select"
 version = "0.8.2"
@@ -3809,45 +3721,6 @@ dependencies = [
  "indexmap",
 ]
 
-[[package]]
-name = "phf"
-version = "0.7.24"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b3da44b85f8e8dfaec21adae67f95d93244b2ecf6ad2a692320598dcc8e6dd18"
-dependencies = [
- "phf_shared",
-]
-
-[[package]]
-name = "phf_codegen"
-version = "0.7.24"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b03e85129e324ad4166b06b2c7491ae27fe3ec353af72e72cd1654c7225d517e"
-dependencies = [
- "phf_generator",
- "phf_shared",
-]
-
-[[package]]
-name = "phf_generator"
-version = "0.7.24"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "09364cc93c159b8b06b1f4dd8a4398984503483891b0c26b867cf431fb132662"
-dependencies = [
- "phf_shared",
- "rand 0.6.5",
-]
-
-[[package]]
-name = "phf_shared"
-version = "0.7.24"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "234f71a15de2288bcb7e3b6515828d22af7ec8598ee6d24c3b526fa0a80b67a0"
-dependencies = [
- "siphasher",
- "unicase 1.4.2",
-]
-
 [[package]]
 name = "pin-project"
 version = "0.4.23"
@@ -4185,25 +4058,6 @@ dependencies = [
  "winapi 0.3.9",
 ]
 
-[[package]]
-name = "rand"
-version = "0.6.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6d71dacdc3c88c1fde3885a3be3fbab9f35724e6ce99467f7d9c5026132184ca"
-dependencies = [
- "autocfg 0.1.7",
- "libc",
- "rand_chacha 0.1.1",
- "rand_core 0.4.2",
- "rand_hc 0.1.0",
- "rand_isaac",
- "rand_jitter",
- "rand_os",
- "rand_pcg",
- "rand_xorshift 0.1.1",
- "winapi 0.3.9",
-]
-
 [[package]]
 name = "rand"
 version = "0.7.3"
@@ -4212,19 +4066,9 @@ checksum = "6a6b1679d49b24bbfe0c803429aa1874472f50d9b363131f0e89fc356b544d03"
 dependencies = [
  "getrandom",
  "libc",
- "rand_chacha 0.2.2",
+ "rand_chacha",
  "rand_core 0.5.1",
- "rand_hc 0.2.0",
-]
-
-[[package]]
-name = "rand_chacha"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "556d3a1ca6600bfcbab7c7c91ccb085ac7fbbcd70e008a98742e7847f4f7bcef"
-dependencies = [
- "autocfg 0.1.7",
- "rand_core 0.3.1",
+ "rand_hc",
 ]
 
 [[package]]
@@ -4261,15 +4105,6 @@ dependencies = [
  "getrandom",
 ]
 
-[[package]]
-name = "rand_hc"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7b40677c7be09ae76218dc623efbf7b18e34bced3f38883af07bb75630a21bc4"
-dependencies = [
- "rand_core 0.3.1",
-]
-
 [[package]]
 name = "rand_hc"
 version = "0.2.0"
@@ -4279,59 +4114,6 @@ dependencies = [
  "rand_core 0.5.1",
 ]
 
-[[package]]
-name = "rand_isaac"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ded997c9d5f13925be2a6fd7e66bf1872597f759fd9dd93513dd7e92e5a5ee08"
-dependencies = [
- "rand_core 0.3.1",
-]
-
-[[package]]
-name = "rand_jitter"
-version = "0.1.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1166d5c91dc97b88d1decc3285bb0a99ed84b05cfd0bc2341bdf2d43fc41e39b"
-dependencies = [
- "libc",
- "rand_core 0.4.2",
- "winapi 0.3.9",
-]
-
-[[package]]
-name = "rand_os"
-version = "0.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7b75f676a1e053fc562eafbb47838d67c84801e38fc1ba459e8f180deabd5071"
-dependencies = [
- "cloudabi 0.0.3",
- "fuchsia-cprng",
- "libc",
- "rand_core 0.4.2",
- "rdrand",
- "winapi 0.3.9",
-]
-
-[[package]]
-name = "rand_pcg"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "abf9b09b01790cfe0364f52bf32995ea3c39f4d2dd011eac241d2914146d0b44"
-dependencies = [
- "autocfg 0.1.7",
- "rand_core 0.4.2",
-]
-
-[[package]]
-name = "rand_xorshift"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cbf7e9e623549b0e21f6e97cf8ecf247c1a8fd2e8a992ae265314300b2455d5c"
-dependencies = [
- "rand_core 0.3.1",
-]
-
 [[package]]
 name = "rand_xorshift"
 version = "0.2.0"
@@ -4466,7 +4248,7 @@ dependencies = [
  "lazy_static",
  "log 0.4.11",
  "mime 0.3.16",
- "mime_guess 2.0.3",
+ "mime_guess",
  "native-tls",
  "percent-encoding 2.1.0",
  "pin-project-lite",
@@ -5011,12 +4793,6 @@ dependencies = [
  "validator_client",
 ]
 
-[[package]]
-name = "siphasher"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0b8de496cf83d4ed58b6be86c3a275b8602f6ffe98d3024a869e124147a9a3ac"
-
 [[package]]
 name = "slab"
 version = "0.3.0"
@@ -5914,19 +5690,6 @@ dependencies = [
  "tokio 0.2.22",
 ]
 
-[[package]]
-name = "tokio-tungstenite"
-version = "0.10.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b8b8fe88007ebc363512449868d7da4389c9400072a3f666f212c7280082882a"
-dependencies = [
- "futures 0.3.5",
- "log 0.4.11",
- "pin-project",
- "tokio 0.2.22",
- "tungstenite",
-]
-
 [[package]]
 name = "tokio-udp"
 version = "0.1.6"
@@ -6027,16 +5790,6 @@ dependencies = [
  "lazy_static",
 ]
 
-[[package]]
-name = "tracing-futures"
-version = "0.2.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ab7bb6f14721aa00656086e9335d363c5c8747bae02ebe32ea2c7dece5689b4c"
-dependencies = [
- "pin-project",
- "tracing",
-]
-
 [[package]]
 name = "trackable"
 version = "1.0.0"
@@ -6090,34 +5843,6 @@ version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "59547bce71d9c38b83d9c0e92b6066c4253371f15005def0c30d9657f50c7642"
 
-[[package]]
-name = "tungstenite"
-version = "0.10.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cfea31758bf674f990918962e8e5f07071a3161bd7c4138ed23e416e1ac4264e"
-dependencies = [
- "base64 0.11.0",
- "byteorder",
- "bytes 0.5.6",
- "http 0.2.1",
- "httparse",
- "input_buffer",
- "log 0.4.11",
- "rand 0.7.3",
- "sha-1",
- "url 2.1.1",
- "utf-8",
-]
-
-[[package]]
-name = "twoway"
-version = "0.1.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "59b11b2b5241ba34be09c3cc85a36e56e48f9888862e19cedf23336d35316ed1"
-dependencies = [
- "memchr",
-]
-
 [[package]]
 name = "typeable"
 version = "0.1.2"
@@ -6153,7 +5878,7 @@ dependencies = [
  "log 0.4.11",
  "merkle_proof",
  "rand 0.7.3",
- "rand_xorshift 0.2.0",
+ "rand_xorshift",
  "rayon",
  "rusqlite",
  "safe_arith",
@@ -6321,18 +6046,6 @@ dependencies = [
  "percent-encoding 2.1.0",
 ]
 
-[[package]]
-name = "urlencoding"
-version = "1.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c9232eb53352b4442e40d7900465dfc534e8cb2dc8f18656fcb2ac16112b5593"
-
-[[package]]
-name = "utf-8"
-version = "0.7.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "05e42f7c18b8f902290b009cde6d651262f956c98bc51bca4cd1d511c9cd85c7"
-
 [[package]]
 name = "uuid"
 version = "0.8.1"
@@ -6462,34 +6175,6 @@ dependencies = [
  "try-lock",
 ]
 
-[[package]]
-name = "warp"
-version = "0.2.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "df341dee97c9ae29dfa5e0b0fbbbf620e0d6a36686389bedf83b3daeb8b0d0ac"
-dependencies = [
- "bytes 0.5.6",
- "futures 0.3.5",
- "headers",
- "http 0.2.1",
- "hyper 0.13.7",
- "log 0.4.11",
- "mime 0.3.16",
- "mime_guess 2.0.3",
- "multipart",
- "pin-project",
- "scoped-tls 1.0.0",
- "serde",
- "serde_json",
- "serde_urlencoded",
- "tokio 0.2.22",
- "tokio-tungstenite",
- "tower-service",
- "tracing",
- "tracing-futures",
- "urlencoding",
-]
-
 [[package]]
 name = "wasi"
 version = "0.9.0+wasi-snapshot-preview1"
diff --git a/Cargo.toml b/Cargo.toml
index 449c18806da..044b6d2f818 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -26,6 +26,7 @@ members = [
     "common/eth2_testnet_config",
     "common/eth2_wallet_manager",
     "common/hashset_delay",
+    "common/http_api_common",
     "common/lighthouse_metrics",
     "common/lighthouse_version",
     "common/logging",
diff --git a/beacon_node/beacon_chain/src/beacon_chain.rs b/beacon_node/beacon_chain/src/beacon_chain.rs
index 40a441a2d79..c6b81cea39f 100644
--- a/beacon_node/beacon_chain/src/beacon_chain.rs
+++ b/beacon_node/beacon_chain/src/beacon_chain.rs
@@ -519,6 +519,20 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         f(&head_lock)
     }
 
+    /// Returns the beacon block at the head of the canonical chain.
+    ///
+    /// See `Self::head` for more information.
+    pub fn head_beacon_block(&self) -> Result<SignedBeaconBlock<T::EthSpec>, Error> {
+        self.with_head(|s| s.beacon_block.clone())
+    }
+
+    /// Returns the beacon state at the head of the canonical chain.
+    ///
+    /// See `Self::head` for more information.
+    pub fn head_beacon_state(&self) -> Result<BeaconState<T::EthSpec>, Error> {
+        self.with_head(|s| s.beacon_state.clone())
+    }
+
     /// Returns info representing the head block and state.
     ///
     /// A summarized version of `Self::head` that involves less cloning.
diff --git a/beacon_node/http_api/Cargo.toml b/beacon_node/http_api/Cargo.toml
index cb21078ba03..ed83f1919a1 100644
--- a/beacon_node/http_api/Cargo.toml
+++ b/beacon_node/http_api/Cargo.toml
@@ -14,3 +14,4 @@ parking_lot = "0.11.0"
 types = { path = "../../consensus/types" }
 hex = "0.4.2"
 beacon_chain = { path = "../beacon_chain" }
+http_api_common = { path = "../../common/http_api_common" }
diff --git a/beacon_node/http_api/src/block_id.rs b/beacon_node/http_api/src/block_id.rs
index 401f8f1d059..74e3cdfbc28 100644
--- a/beacon_node/http_api/src/block_id.rs
+++ b/beacon_node/http_api/src/block_id.rs
@@ -1,6 +1,6 @@
 use beacon_chain::{BeaconChain, BeaconChainTypes};
 use std::str::FromStr;
-use types::{Hash256, Slot};
+use types::{Hash256, SignedBeaconBlock, Slot};
 
 #[derive(Debug)]
 pub enum BlockId {
@@ -38,6 +38,25 @@ impl BlockId {
             BlockId::Root(root) => Ok(*root),
         }
     }
+
+    pub fn block<T: BeaconChainTypes>(
+        &self,
+        chain: &BeaconChain<T>,
+    ) -> Result<SignedBeaconBlock<T::EthSpec>, warp::Rejection> {
+        let block_root = match self {
+            BlockId::Head => {
+                return chain
+                    .head_beacon_block()
+                    .map_err(crate::reject::beacon_chain_error)
+            }
+            other => other.root(chain),
+        }?;
+
+        chain
+            .get_block(&block_root)
+            .map_err(crate::reject::beacon_chain_error)
+            .and_then(|root_opt| root_opt.ok_or_else(|| warp::reject::not_found()))
+    }
 }
 
 impl FromStr for BlockId {
diff --git a/beacon_node/http_api/src/lib.rs b/beacon_node/http_api/src/lib.rs
index f2e0eb7785c..74807b0b636 100644
--- a/beacon_node/http_api/src/lib.rs
+++ b/beacon_node/http_api/src/lib.rs
@@ -4,6 +4,8 @@ mod state_id;
 
 use beacon_chain::{BeaconChain, BeaconChainTypes};
 use block_id::BlockId;
+use http_api_common as api;
+use serde::Serialize;
 use state_id::StateId;
 use std::sync::Arc;
 use warp::Filter;
@@ -40,16 +42,39 @@ pub async fn serve<T: BeaconChainTypes>(ctx: Arc<Context<T>>) {
         .clone()
         .and(warp::path("root"))
         .and(warp::path::end())
-        .and_then(|state_id: StateId, chain: Arc<BeaconChain<T>>| async move {
-            state_id.root(&chain).map(|resp| warp::reply::json(&resp))
+        .and_then(|state_id: StateId, chain: Arc<BeaconChain<T>>| {
+            blocking_json_task(move || {
+                state_id
+                    .root(&chain)
+                    .map(api::RootData::from)
+                    .map(api::GenericResponse::from)
+            })
         });
 
     let beacon_state_fork = beacon_states_path
         .clone()
         .and(warp::path("fork"))
         .and(warp::path::end())
-        .and_then(|state_id: StateId, chain: Arc<BeaconChain<T>>| async move {
-            state_id.root(&chain).map(|resp| warp::reply::json(&resp))
+        .and_then(|state_id: StateId, chain: Arc<BeaconChain<T>>| {
+            blocking_json_task(move || state_id.fork(&chain).map(api::GenericResponse::from))
+        });
+
+    let beacon_state_finality_checkpoints = beacon_states_path
+        .clone()
+        .and(warp::path("finality_checkpoints"))
+        .and(warp::path::end())
+        .and_then(|state_id: StateId, chain: Arc<BeaconChain<T>>| {
+            blocking_json_task(move || {
+                state_id
+                    .map_state(&chain, |state| {
+                        Ok(api::FinalityCheckpointsData {
+                            previous_justified: state.previous_justified_checkpoint,
+                            current_justified: state.current_justified_checkpoint,
+                            finalized: state.finalized_checkpoint,
+                        })
+                    })
+                    .map(api::GenericResponse::from)
+            })
         });
 
     /*
@@ -66,13 +91,36 @@ pub async fn serve<T: BeaconChainTypes>(ctx: Arc<Context<T>>) {
         .clone()
         .and(warp::path("root"))
         .and(warp::path::end())
-        .and_then(|block_id: BlockId, chain: Arc<BeaconChain<T>>| async move {
-            block_id.root(&chain).map(|resp| warp::reply::json(&resp))
+        .and_then(|block_id: BlockId, chain: Arc<BeaconChain<T>>| {
+            blocking_json_task(move || {
+                block_id
+                    .root(&chain)
+                    .map(api::RootData::from)
+                    .map(api::GenericResponse::from)
+            })
         });
 
     let routes = beacon_state_root
         .or(beacon_state_fork)
+        .or(beacon_state_finality_checkpoints)
         .or(beacon_block_root);
 
     warp::serve(routes).run(([127, 0, 0, 1], 3030)).await;
 }
+
+async fn blocking_task<F, T>(func: F) -> T
+where
+    F: Fn() -> T,
+{
+    tokio::task::block_in_place(func)
+}
+
+async fn blocking_json_task<F, T>(func: F) -> Result<warp::reply::Json, warp::Rejection>
+where
+    F: Fn() -> Result<T, warp::Rejection>,
+    T: Serialize,
+{
+    blocking_task(func)
+        .await
+        .map(|resp| warp::reply::json(&resp))
+}
diff --git a/beacon_node/http_api/src/state_id.rs b/beacon_node/http_api/src/state_id.rs
index b1553cc3849..580a4086a7e 100644
--- a/beacon_node/http_api/src/state_id.rs
+++ b/beacon_node/http_api/src/state_id.rs
@@ -1,6 +1,7 @@
+use crate::BlockId;
 use beacon_chain::{BeaconChain, BeaconChainTypes};
 use std::str::FromStr;
-use types::{Hash256, Slot};
+use types::{BeaconState, Fork, Hash256, Slot};
 
 #[derive(Debug)]
 pub enum StateId {
@@ -17,17 +18,68 @@ impl StateId {
         &self,
         chain: &BeaconChain<T>,
     ) -> Result<Hash256, warp::Rejection> {
-        match self {
-            StateId::Head => chain
-                .head_info()
-                .map(|head| head.state_root)
-                .map_err(crate::reject::beacon_chain_error),
-            StateId::Genesis => Ok(chain.genesis_state_root),
-            StateId::Finalized => todo!(),
-            StateId::Justified => todo!(),
-            StateId::Slot(_) => todo!(),
-            StateId::Root(root) => Ok(*root),
-        }
+        let block = match self {
+            StateId::Head => {
+                return chain
+                    .head_info()
+                    .map(|head| head.state_root)
+                    .map_err(crate::reject::beacon_chain_error)
+            }
+            StateId::Genesis => return Ok(chain.genesis_state_root),
+            StateId::Finalized => BlockId::Finalized.block(chain),
+            StateId::Justified => BlockId::Justified.block(chain),
+            StateId::Slot(slot) => BlockId::Slot(*slot).block(chain),
+            StateId::Root(root) => return Ok(*root),
+        }?;
+
+        Ok(block.state_root())
+    }
+
+    pub fn fork<T: BeaconChainTypes>(
+        &self,
+        chain: &BeaconChain<T>,
+    ) -> Result<Fork, warp::Rejection> {
+        self.map_state(chain, |state| Ok(state.fork.clone()))
+    }
+
+    pub fn state<T: BeaconChainTypes>(
+        &self,
+        chain: &BeaconChain<T>,
+    ) -> Result<BeaconState<T::EthSpec>, warp::Rejection> {
+        let (state_root, slot_opt) = match self {
+            StateId::Head => {
+                return chain
+                    .head_beacon_state()
+                    .map_err(crate::reject::beacon_chain_error)
+            }
+            StateId::Slot(slot) => (self.root(chain)?, Some(*slot)),
+            other => (other.root(chain)?, None),
+        };
+
+        chain
+            .get_state(&state_root, slot_opt)
+            .map_err(crate::reject::beacon_chain_error)
+            .and_then(|opt| opt.ok_or_else(|| warp::reject::not_found()))
+    }
+
+    pub fn map_state<T: BeaconChainTypes, F, U>(
+        &self,
+        chain: &BeaconChain<T>,
+        func: F,
+    ) -> Result<U, warp::Rejection>
+    where
+        F: Fn(&BeaconState<T::EthSpec>) -> Result<U, warp::Rejection>,
+    {
+        let state = match self {
+            StateId::Head => {
+                return chain
+                    .map_head(|snapshot| func(&snapshot.beacon_state))
+                    .map_err(crate::reject::beacon_chain_error)?
+            }
+            other => other.state(chain)?,
+        };
+
+        func(&state)
     }
 }
 
diff --git a/common/http_api_common/Cargo.toml b/common/http_api_common/Cargo.toml
new file mode 100644
index 00000000000..d63e19d8ed8
--- /dev/null
+++ b/common/http_api_common/Cargo.toml
@@ -0,0 +1,12 @@
+[package]
+name = "http_api_common"
+version = "0.1.0"
+authors = ["Paul Hauner <paul@paulhauner.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+serde = { version = "1.0.110", features = ["derive"] }
+types = { path = "../../consensus/types" }
+hex = "0.4.2"
diff --git a/common/http_api_common/src/lib.rs b/common/http_api_common/src/lib.rs
new file mode 100644
index 00000000000..b1f92ebe541
--- /dev/null
+++ b/common/http_api_common/src/lib.rs
@@ -0,0 +1,31 @@
+use serde::{Deserialize, Serialize};
+use types::{Checkpoint, Hash256};
+
+#[derive(Serialize)]
+pub struct GenericResponse<T: Serialize> {
+    pub data: T,
+}
+
+impl<T: Serialize> From<T> for GenericResponse<T> {
+    fn from(data: T) -> Self {
+        Self { data }
+    }
+}
+
+#[derive(Serialize, Deserialize)]
+pub struct RootData {
+    pub root: Hash256,
+}
+
+impl From<Hash256> for RootData {
+    fn from(root: Hash256) -> Self {
+        Self { root }
+    }
+}
+
+#[derive(Serialize, Deserialize)]
+pub struct FinalityCheckpointsData {
+    pub previous_justified: Checkpoint,
+    pub current_justified: Checkpoint,
+    pub finalized: Checkpoint,
+}