diff --git a/README.md b/README.md
index 518a9bf..c8d6b60 100644
--- a/README.md
+++ b/README.md
@@ -4,8 +4,9 @@
 
 MultiAuth is a library that standardizes multi-provider authentication for web applications. Currently supported providers:
 
-- Github
-- Facebook
+- Github.com
+- Facebook.com
+- Vk.com
 
 ## Installation
 
diff --git a/spec/providers/vk_spec.cr b/spec/providers/vk_spec.cr
new file mode 100644
index 0000000..a067711
--- /dev/null
+++ b/spec/providers/vk_spec.cr
@@ -0,0 +1,45 @@
+require "../spec_helper"
+
+describe MultiAuth do
+  context "vk" do
+    it "generates authorize_uri" do
+      uri = MultiAuth.make("vk", "/callback").authorize_uri
+      uri.should eq("https://oauth.vk.com/authorize?client_id=vk_id&redirect_uri=%2Fcallback&response_type=code&scope=email")
+    end
+
+    it "fetch user" do
+      WebMock.wrap do
+        WebMock
+          .stub(:post, "https://oauth.vk.com/access_token")
+          .with(
+          body: "client_id=vk_id&client_secret=vk_secret&redirect_uri=%2Fcallback&grant_type=authorization_code&code=123",
+          headers: {"Accept" => "application/json", "Content-Length" => "103", "Host" => "oauth.vk.com", "Content-type" => "application/x-www-form-urlencoded"})
+          .to_return(
+          body: %({
+                  "access_token" : "1111",
+                  "expires_in" : 899,
+                  "refresh_token" : null,
+                  "scope" : "email",
+                  "user_id" : "3333",
+                  "email" : "s@msa7.ru"
+                })
+        )
+
+        WebMock
+          .stub(:get, %(https://api.vk.com/method/users.get?fields=about,photo_max_orig,city,country,domain,contacts,site&user_id="3333"&v=5.52))
+          .to_return(
+          body: %({"response": [{
+            "first_name" : "Sergey",
+            "last_name" : "Makridenkov",
+            "id" : 3333
+          }]})
+        )
+
+        user = MultiAuth.make("vk", "/callback").user({"code" => "123"}).as(MultiAuth::User)
+
+        user.name.should eq("Makridenkov Sergey")
+        user.uid.should eq("3333")
+      end
+    end
+  end
+end
diff --git a/spec/spec_helper.cr b/spec/spec_helper.cr
index 74c4acf..42728e0 100644
--- a/spec/spec_helper.cr
+++ b/spec/spec_helper.cr
@@ -5,3 +5,4 @@ require "../src/multi_auth"
 MultiAuth.config("google", "google_id", "google_secret")
 MultiAuth.config("github", "github_id", "github_secret")
 MultiAuth.config("facebook", "facebook_id", "facebook_secret")
+MultiAuth.config("vk", "vk_id", "vk_secret")
diff --git a/src/crystal_std_patch/access_token.cr b/src/crystal_std_patch/access_token.cr
new file mode 100644
index 0000000..8e24083
--- /dev/null
+++ b/src/crystal_std_patch/access_token.cr
@@ -0,0 +1,70 @@
+# TODO remove hack after release
+# https://github.com/crystal-lang/crystal/commit/31099237c87a3851c8cb2a78df5ff00bac7364c6
+
+# Base class for the two possible access tokens: Bearer and Mac.
+#
+# Use `#authenticate` to authenticate an `HTTP::Client`.
+abstract class OAuth2::AccessToken
+  def self.new(pull : JSON::PullParser)
+    token_type = nil
+    access_token = nil
+    expires_in = nil
+    refresh_token = nil
+    scope = nil
+    mac_algorithm = nil
+    mac_key = nil
+    extra = nil
+
+    pull.read_object do |key|
+      case key
+      when "token_type"    then token_type = pull.read_string
+      when "access_token"  then access_token = pull.read_string
+      when "expires_in"    then expires_in = pull.read_int
+      when "refresh_token" then refresh_token = pull.read_string_or_null
+      when "scope"         then scope = pull.read_string_or_null
+      when "mac_algorithm" then mac_algorithm = pull.read_string
+      when "mac_key"       then mac_key = pull.read_string
+      else
+        extra ||= {} of String => String
+        extra[key] = pull.read_raw
+      end
+    end
+
+    access_token = access_token.not_nil!
+    token_type ||= "bearer"
+
+    case token_type.downcase
+    when "bearer"
+      Bearer.new(access_token, expires_in, refresh_token, scope, extra)
+    when "mac"
+      Mac.new(access_token, expires_in, mac_algorithm.not_nil!, mac_key.not_nil!, refresh_token, scope, Time.now.epoch, extra)
+    else
+      raise "Uknown token_type in access token json: #{token_type}"
+    end
+  end
+
+  property access_token : String
+  property expires_in : Int64?
+  property refresh_token : String?
+  property scope : String?
+
+  # JSON key-value pairs that are outside of the OAuth2 spec are
+  # stored in this property in case they are needed. Their value
+  # is the raw JSON string found in the JSON value (with possible
+  # changes in the string format, but preserving JSON semantic).
+  # For example if the value was `[1, 2, 3]` then the value in this hash
+  # will be the string "[1,2,3]".
+  property extra : Hash(String, String)?
+
+  def initialize(@access_token : String, expires_in : Int?, @refresh_token : String? = nil, @scope : String? = nil, @extra = nil)
+    @expires_in = expires_in.try &.to_i64
+  end
+
+  abstract def authenticate(request : HTTP::Request, tls)
+
+  def authenticate(client : HTTP::Client)
+    client.before_request do |request|
+      authenticate request, client.tls?
+    end
+  end
+end
diff --git a/src/crystal_std_patch/access_token_mac.cr b/src/crystal_std_patch/access_token_mac.cr
new file mode 100644
index 0000000..998ac6c
--- /dev/null
+++ b/src/crystal_std_patch/access_token_mac.cr
@@ -0,0 +1,76 @@
+# TODO remove hack after release
+# https://github.com/crystal-lang/crystal/commit/31099237c87a3851c8cb2a78df5ff00bac7364c6
+
+require "secure_random"
+require "openssl/hmac"
+require "base64"
+require "./access_token"
+
+class OAuth2::AccessToken::Mac < OAuth2::AccessToken
+  def self.new(pull : JSON::PullParser)
+    OAuth2::AccessToken.new(pull).as(self)
+  end
+
+  property mac_algorithm : String
+  property mac_key : String
+  property issued_at : Int64
+
+  def initialize(access_token, expires_in, @mac_algorithm, @mac_key, refresh_token = nil, scope = nil, @issued_at = Time.now.epoch, extra = nil)
+    super(access_token, expires_in, refresh_token, scope, extra)
+  end
+
+  def token_type
+    "Mac"
+  end
+
+  def authenticate(request : HTTP::Request, tls)
+    ts = Time.now.epoch
+    nonce = "#{ts - @issued_at}:#{SecureRandom.hex}"
+    method = request.method
+    uri = request.resource
+    host, port = host_and_port request, tls
+    ext = ""
+
+    mac = Mac.signature ts, nonce, method, uri, host, port, ext, mac_algorithm, mac_key
+
+    header = %(MAC id="#{access_token}", nonce="#{nonce}", ts="#{ts}", mac="#{mac}")
+    request.headers["Authorization"] = header
+  end
+
+  def self.signature(ts, nonce, method, uri, host, port, ext, mac_algorithm, mac_key)
+    normalized_request_string = "#{ts}\n#{nonce}\n#{method}\n#{uri}\n#{host}\n#{port}\n#{ext}\n"
+
+    digest = case mac_algorithm
+             when "hmac-sha-1"   then :sha1
+             when "hmac-sha-256" then :sha256
+             else                     raise "Unsupported algorithm: #{mac_algorithm}"
+             end
+    Base64.strict_encode OpenSSL::HMAC.digest(digest, mac_key, normalized_request_string)
+  end
+
+  def to_json(json : JSON::Builder)
+    json.object do
+      json.field "token_type", "mac"
+      json.field "access_token", access_token
+      json.field "expires_in", expires_in
+      json.field "refresh_token", refresh_token if refresh_token
+      json.field "scope", scope if scope
+      json.field "mac_algorithm", mac_algorithm
+      json.field "mac_key", mac_key
+    end
+  end
+
+  def_equals_and_hash access_token, expires_in, mac_algorithm, mac_key, refresh_token, scope
+
+  private def host_and_port(request, tls)
+    host_header = request.headers["Host"]
+    if colon_index = host_header.index ':'
+      host = host_header[0...colon_index]
+      port = host_header[colon_index + 1..-1].to_i
+    else
+      host = host_header
+      port = tls ? 443 : 80
+    end
+    {host, port}
+  end
+end
diff --git a/src/multi_auth.cr b/src/multi_auth.cr
index 3894c0e..12f9a91 100644
--- a/src/multi_auth.cr
+++ b/src/multi_auth.cr
@@ -1,4 +1,5 @@
 require "oauth2"
+require "./crystal_std_patch/**"
 require "./multi_auth/**"
 
 module MultiAuth
diff --git a/src/multi_auth/engine.cr b/src/multi_auth/engine.cr
index 54d5165..c2173c1 100644
--- a/src/multi_auth/engine.cr
+++ b/src/multi_auth/engine.cr
@@ -1,10 +1,12 @@
 class MultiAuth::Engine
   def initialize(provider : String, redirect_uri : String)
     provider_class = case provider
-                     # when "google" then Provider::Google
+                     # when "google"  then Provider::Google
                      when "github"   then Provider::Github
                      when "facebook" then Provider::Facebook
-                     else                 raise "Provider #{provider} not implemented"
+                     when "vk"       then Provider::Vk
+                     else
+                       raise "Provider #{provider} not implemented"
                      end
 
     client_id, client_secret = MultiAuth.configuration[provider]
diff --git a/src/multi_auth/providers/facebook.cr b/src/multi_auth/providers/facebook.cr
index b8d5fc4..21e5d3e 100644
--- a/src/multi_auth/providers/facebook.cr
+++ b/src/multi_auth/providers/facebook.cr
@@ -52,10 +52,6 @@ class MultiAuth::Provider::Facebook < MultiAuth::Provider
     fb_user
   end
 
-  private def api(access_token)
-    api
-  end
-
   private def client
     OAuth2::Client.new(
       "www.facebook.com",
diff --git a/src/multi_auth/providers/vk.cr b/src/multi_auth/providers/vk.cr
new file mode 100644
index 0000000..57f4911
--- /dev/null
+++ b/src/multi_auth/providers/vk.cr
@@ -0,0 +1,100 @@
+class MultiAuth::Provider::Vk < MultiAuth::Provider
+  def authorize_uri(scope = nil)
+    @scope = scope || "email"
+    client.get_authorize_uri(@scope)
+  end
+
+  def user(params : Hash(String, String))
+    vk_user = fetch_vk_user(params["code"])
+
+    user = User.new("vk", vk_user.id, vk_user.name, vk_user.raw_json.not_nil!)
+
+    user.email = vk_user.email
+    user.first_name = vk_user.first_name
+    user.last_name = vk_user.last_name
+    user.nickname = vk_user.domain
+    user.description = vk_user.about
+    user.image = vk_user.photo_max_orig
+    user.phone = vk_user.mobile_phone || vk_user.home_phone
+    user.access_token = vk_user.access_token
+
+    location = [] of String
+    location << vk_user.city.not_nil!.title if vk_user.city
+    location << vk_user.country.not_nil!.title if vk_user.country
+    user.location = location.join(", ") unless location.empty?
+
+    urls = {} of String => String
+    urls["web"] = vk_user.site.not_nil! if vk_user.site
+    user.urls = urls unless urls.empty?
+
+    user
+  end
+
+  class VkTitle
+    JSON.mapping(
+      title: String
+    )
+  end
+
+  class VkUser
+    property raw_json : String?
+    property access_token : OAuth2::AccessToken?
+    property email : String?
+    property id : String?
+
+    def name
+      "#{last_name} #{first_name}"
+    end
+
+    JSON.mapping(
+      id: {type: String, converter: String::RawConverter},
+      last_name: String?,
+      first_name: String?,
+      site: String?,
+      city: VkTitle?,
+      country: VkTitle?,
+      domain: String?,
+      about: String?,
+      photo_max_orig: String?,
+      mobile_phone: String?,
+      home_phone: String?
+    )
+  end
+
+  class VkResponse
+    JSON.mapping(
+      response: Array(VkUser),
+    )
+  end
+
+  private def fetch_vk_user(code)
+    access_token = client.get_access_token_using_authorization_code(code)
+
+    api = HTTP::Client.new("api.vk.com", tls: true)
+    access_token.authenticate(api)
+
+    user_id = access_token.extra.not_nil!["user_id"]
+    user_email = access_token.extra.not_nil!["email"]
+
+    fields = "about,photo_max_orig,city,country,domain,contacts,site"
+    raw_json = api.get("/method/users.get?fields=#{fields}&user_id=#{user_id}&v=5.52").body
+
+    vk_user = VkResponse.from_json(raw_json).response.first
+    vk_user.email = user_email
+    vk_user.access_token = access_token
+    vk_user.raw_json = raw_json
+
+    vk_user
+  end
+
+  private def client
+    OAuth2::Client.new(
+      "oauth.vk.com",
+      client_id,
+      client_secret,
+      redirect_uri: redirect_uri,
+      authorize_uri: "/authorize",
+      token_uri: "/access_token"
+    )
+  end
+end