diff --git a/builtin.aqua b/builtin.aqua
index ed5d98f..c11fdf6 100644
--- a/builtin.aqua
+++ b/builtin.aqua
@@ -66,6 +66,10 @@ service Op("op"):
     string_from_b58(b: string) -> string
     bytes_to_b58(bs: []u8) -> string
     bytes_from_b58(b: string) -> []u8
+    -- Applies SHA256 to the given string
+    -- Argument: s - string to apply sha256 to
+    -- Returns: returns sha256 multihash encoded as base58
+    sha256_string(s: string) -> string
 
 service Peer("peer"):
     -- Checks if there is a direct connection to the peer identified by a given PeerId
@@ -97,6 +101,14 @@ service Kademlia("kad"):
     -- Instructs node to return the locally-known nodes
     -- in the Kademlia neighborhood for a given key
     neighborhood(key: PeerId, already_hashed: bool) -> []PeerId
+    -- Merges given lists and sorts them by distance to target
+    -- Arguments:
+    -- target – base58 string; result is sorted by XOR distance to target
+    -- left – list of base58 strings
+    -- right – list of base58 strings
+    -- count – how many items to return
+    -- Returns: list of base58 strings sorted by distance to target; list will contain at most count elements
+    merge(target: string, left: []string, right: []string, count: u32) -> []string
 
 service Srv("srv"):
     -- Used to create a service on a certain node
@@ -120,6 +132,11 @@ service Srv("srv"):
     -- service_id – ID of the service whose interface you want to name.
     add_alias(alias: string, service_id: string)
 
+    -- Resolves given alias to a service id
+    -- If there's no such alias, throws an error
+    -- Returns: service id associated with the given alias
+    resolve_alias(alias: string) -> string
+
     -- Retrieves the functional interface of a service running
     -- on the node specified in the service call
     -- Argument: service_id – ID of the service whose interface you want to retrieve.