diff --git a/Cargo.lock b/Cargo.lock
index ddbe4f280..a83447acf 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,3 +1,5 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
 [[package]]
 name = "arrayvec"
 version = "0.4.10"
@@ -16,6 +18,11 @@ name = "bitflags"
 version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "byteorder"
+version = "1.2.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "cfg-if"
 version = "0.1.6"
@@ -109,6 +116,15 @@ name = "fuchsia-zircon-sys"
 version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "hashbrown"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "byteorder 1.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "scopeguard 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "itoa"
 version = "0.4.3"
@@ -133,20 +149,12 @@ dependencies = [
  "scopeguard 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "log"
-version = "0.4.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "medea"
 version = "0.1.0"
 dependencies = [
  "chrono 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "hashbrown 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "slog 2.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "slog-async 2.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "slog-json 2.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -457,6 +465,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum arrayvec 0.4.10 (registry+https://github.com/rust-lang/crates.io-index)" = "92c7fb76bc8826a8b33b4ee5bb07a247a81e76764ab4d55e8f73e3a4d8808c71"
 "checksum autocfg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "a6d640bee2da49f60a4068a7fae53acde8982514ab7bae8b8cea9e88cbcfd799"
 "checksum bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "228047a76f468627ca71776ecdebd732a3423081fcf5125585bcd7c49886ce12"
+"checksum byteorder 1.2.7 (registry+https://github.com/rust-lang/crates.io-index)" = "94f88df23a25417badc922ab0f5716cc1330e87f71ddd9203b3a3ccd9cedf75d"
 "checksum cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "082bb9b28e00d3c9d39cc03e64ce4cea0f1bb9b3fde493f0cbc008472d22bdf4"
 "checksum chrono 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "45912881121cb26fad7c38c17ba7daa18764771836b34fab7d3fbd93ed633878"
 "checksum cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "ddfc5b9aa5d4507acaf872de71051dfd0e309860e88966e1051e462a077aac4f"
@@ -467,11 +476,11 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum crossbeam-utils 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)" = "41ee4864f4797060e52044376f7d107429ce1fb43460021b126424b7180ee21a"
 "checksum fuchsia-zircon 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2e9763c69ebaae630ba35f74888db465e49e259ba1bc0eda7d06f4a067615d82"
 "checksum fuchsia-zircon-sys 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "3dcaa9ae7725d12cdb85b3ad99a434db70b468c09ded17e012d86b5c1010f7a7"
+"checksum hashbrown 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "3bae29b6653b3412c2e71e9d486db9f9df5d701941d86683005efb9f2d28e3da"
 "checksum itoa 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "1306f3464951f30e30d12373d31c79fbd52d236e5e896fd92f96ec7babbbe60b"
 "checksum lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a374c89b9db55895453a74c1e38861d9deec0b01b405a82516e9d5de4820dea1"
 "checksum libc 0.2.47 (registry+https://github.com/rust-lang/crates.io-index)" = "48450664a984b25d5b479554c29cc04e3150c97aa4c01da5604a2d4ed9151476"
 "checksum lock_api 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "62ebf1391f6acad60e5c8b43706dde4582df75c06698ab44511d15016bc2442c"
-"checksum log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "c84ec4b527950aa83a329754b01dbe3f58361d1c5efacd1f6d68c494d08a17c6"
 "checksum memoffset 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "0f9dc261e2b62d7a622bf416ea3c5245cdd5d9a7fcc428c0d06804dfce1775b3"
 "checksum nodrop 0.1.13 (registry+https://github.com/rust-lang/crates.io-index)" = "2f9667ddcc6cc8a43afc9b7917599d7216aa09c463919ea32c59ed6cac8bc945"
 "checksum num-integer 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)" = "e83d528d2677f0518c570baf2b7abdcf0cd2d248860b68507bdcb3e91d4c0cea"
diff --git a/Cargo.toml b/Cargo.toml
index 1f2a22047..7281bb4ae 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,8 +11,8 @@ repository = "https://github.com/instrumentisto/medea"
 
 [dependencies]
 chrono = "0.4"
-log = "0.4"
-slog = { version = "2.4", features = ["max_level_info", "release_max_level_warn"] }
+hashbrown = "0.1"
+slog = { version = "2.4", features = ["max_level_debug", "release_max_level_warn"] }
 slog-async = "2.3"
 slog-json = "2.3"
 slog-scope = "4.1"
diff --git a/src/api/control/member.rs b/src/api/control/member.rs
new file mode 100644
index 000000000..162ab45b3
--- /dev/null
+++ b/src/api/control/member.rs
@@ -0,0 +1,86 @@
+//! Member definitions and implementations.
+
+use hashbrown::HashMap;
+
+use crate::log::prelude::*;
+
+/// ID of [`Member`].
+pub type Id = u64;
+
+/// Media server user with its ID and credentials.
+#[derive(Clone, Debug)]
+pub struct Member {
+    /// ID of [`Member`].
+    pub id: Id,
+    /// Credentials to authorize [`Member`] with.
+    pub credentials: String,
+}
+
+/// Repository that stores [`Member`]s.
+#[derive(Default)]
+pub struct MemberRepository {
+    members: HashMap<Id, Member>,
+}
+
+impl MemberRepository {
+    /// Creates new [`Member`]s repository with passed-in [`Member`]s.
+    pub fn new(members: HashMap<Id, Member>) -> Self {
+        MemberRepository { members }
+    }
+
+    /// Returns [`Member`] by its ID.
+    pub fn get(&self, id: Id) -> Option<Member> {
+        debug!("retrieve member by id: {}", id);
+        self.members.get(&id).map(|member| member.clone())
+    }
+
+    /// Returns [`Member`] by its credentials.
+    pub fn get_by_credentials(&self, credentials: &str) -> Option<Member> {
+        debug!("retrieve member by credentials: {}", credentials);
+        self.members
+            .values()
+            .find(|member| member.credentials.eq(credentials))
+            .map(|member| member.clone())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn test_members() -> HashMap<Id, Member> {
+        hashmap! {
+            1 => Member{id: 1, credentials: "caller_credentials".to_owned()},
+            2 => Member{id: 2, credentials: "responder_credentials".to_owned()},
+        }
+    }
+
+    #[test]
+    fn returns_member_by_id() {
+        let repo = MemberRepository::new(test_members());
+
+        let res = repo.get(1);
+        assert!(res.is_some());
+        let member = res.unwrap();
+        assert_eq!(member.id, 1);
+    }
+
+    #[test]
+    fn returns_member_by_credentials() {
+        let repo = MemberRepository::new(test_members());
+
+        let res = repo.get_by_credentials("responder_credentials");
+        assert!(res.is_some());
+        let member = res.unwrap();
+        assert_eq!(member.id, 2);
+        assert_eq!(member.credentials, "responder_credentials");
+    }
+
+    #[test]
+    fn returns_error_not_found() {
+        let repo = MemberRepository::new(test_members());
+
+        let res = repo.get(999);
+        assert!(res.is_none());
+    }
+}
diff --git a/src/api/control/mod.rs b/src/api/control/mod.rs
new file mode 100644
index 000000000..edcb52719
--- /dev/null
+++ b/src/api/control/mod.rs
@@ -0,0 +1,5 @@
+//! Implementation of Control API.
+
+pub mod member;
+
+pub use self::member::{Id, Member, MemberRepository};
diff --git a/src/api/mod.rs b/src/api/mod.rs
new file mode 100644
index 000000000..3c2414f0c
--- /dev/null
+++ b/src/api/mod.rs
@@ -0,0 +1,3 @@
+//! API implementations provided by application.
+
+pub mod control;
diff --git a/src/main.rs b/src/main.rs
index 5acb346eb..2a30589d0 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,11 +1,27 @@
-use crate::log::prelude::*;
+//! Medea media server application.
 
+use crate::{
+    api::control::{Member, MemberRepository},
+    log::prelude::*,
+};
+
+#[macro_use]
+mod utils;
+
+mod api;
 mod log;
 
 fn main() {
     let logger = log::new_dual_logger(std::io::stdout(), std::io::stderr());
     let _scope_guard = slog_scope::set_global_logger(logger);
 
-    info!("Hooray!");
-    warn!("It works");
+    let repo = MemberRepository::new(hashmap! {
+        1 => Member{id: 1, credentials: "caller_credentials".to_owned()},
+        2 => Member{id: 2, credentials: "responder_credentials".to_owned()},
+    });
+    if let Some(member) = repo.get(1) {
+        info!("{:?}", member);
+        info!("Hooray!");
+        warn!("It works");
+    }
 }
diff --git a/src/utils/mod.rs b/src/utils/mod.rs
new file mode 100644
index 000000000..cfc1b0155
--- /dev/null
+++ b/src/utils/mod.rs
@@ -0,0 +1,32 @@
+//! Helper utils used in project.
+
+/// Creates new [`::hashbrown::HashMap`] from a list of key-value pairs.
+///
+/// ## Example
+///
+/// ```rust
+/// let map = hashmap! {
+///     "a" => 1,
+///     "b" => 2,
+/// };
+/// assert_eq!(map["a"], 1);
+/// assert_eq!(map["b"], 2);
+/// assert_eq!(map.get("c"), None);
+/// ```
+#[macro_export]
+macro_rules! hashmap {
+    (@single $($x:tt)*) => (());
+    (@count $($rest:expr),*) => (<[()]>::len(&[$(hashmap!(@single $rest)),*]));
+
+    ($($key:expr => $value:expr,)+) => { hashmap!($($key => $value),+) };
+    ($($key:expr => $value:expr),*) => {
+        {
+            let _cap = hashmap!(@count $($key),*);
+            let mut _map = ::hashbrown::HashMap::with_capacity(_cap);
+            $(
+                let _ = _map.insert($key, $value);
+            )*
+            _map
+        }
+    };
+}