diff --git a/.github/pull_request_template.md b/.github/pull_request_template.md
index 94f5eecc..29af0e09 100644
--- a/.github/pull_request_template.md
+++ b/.github/pull_request_template.md
@@ -10,8 +10,16 @@ Screenshots/screencasts of the pull request introduced functionality.
 
 List of steps to manually test introduced functionality:
 
-- Log in
-- Go to http://localhost:3000
+- Go to http://localhost:3000/graphiql
+- Make request using schema:
+```graphql
+  query {
+    me {
+      id
+      name
+    }
+  }
+```
 
 ### Deploy notes
 
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index b9342684..8693b440 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -34,4 +34,7 @@ jobs:
 
       - name: Run rubocop
         run: bin/rubocop
+
+      - name: Run tests
+        run: bin/rspec
 ...
diff --git a/.rubocop.yml b/.rubocop.yml
index 924e11d2..da1f3d02 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -8,6 +8,14 @@ require:
 
 AllCops:
   NewCops: enable
+  Exclude:
+    - bin/**/*
+    - db/**/*
+    - vendor/**/*
+    - tmp/**/*
+    - app/controllers/graphql_controller.rb
+    - app/graphql/task_tracker_itis_schema.rb
+    - app/graphql/types/mutation_type.rb
 
 I18n/GetText/DecorateString:
   Enabled: false
diff --git a/Gemfile b/Gemfile
index b2b828f2..8a834768 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,6 +6,7 @@ ruby "2.7.4"
 gem "action_policy"
 gem "active_model_serializers"
 gem "enumerize"
+gem "graphql"
 gem "interactor", "~> 3.0"
 # Bundle edge Rails instead: gem "rails", github: "rails/rails", branch: "main"
 gem "rails", "~> 6.1.7"
@@ -60,6 +61,7 @@ group :development do
   gem "listen", "~> 3.3"
   gem "rack-mini-profiler", "~> 2.0"
   # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
+  gem "graphiql-rails"
   gem "spring"
 end
 
diff --git a/Gemfile.lock b/Gemfile.lock
index 0e859d0c..f1e1f7a8 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -111,6 +111,11 @@ GEM
     ffi (1.15.5)
     globalid (1.2.1)
       activesupport (>= 6.1)
+    graphiql-rails (1.9.0)
+      railties
+      sprockets-rails
+    graphql (2.1.6)
+      racc (~> 1.4)
     i18n (1.14.1)
       concurrent-ruby (~> 1.0)
     interactor (3.1.2)
@@ -346,6 +351,8 @@ DEPENDENCIES
   enumerize
   factory_bot_rails
   faker
+  graphiql-rails
+  graphql
   interactor (~> 3.0)
   jbuilder (~> 2.7)
   jwt
diff --git a/app/controllers/graphql_controller.rb b/app/controllers/graphql_controller.rb
new file mode 100644
index 00000000..a62c440e
--- /dev/null
+++ b/app/controllers/graphql_controller.rb
@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+class GraphqlController < ApplicationController
+  # If accessing from outside this domain, nullify the session
+  # This allows for outside API access while preventing CSRF attacks,
+  # but you'll have to authenticate your user separately
+  protect_from_forgery with: :null_session
+
+  skip_verify_authorized
+
+  def execute
+    variables = prepare_variables(params[:variables])
+    query = params[:query]
+    operation_name = params[:operationName]
+    context = {
+      current_user: current_user
+    }
+    result = TaskTrackerItisSchema.execute(query, variables: variables, context: context, operation_name: operation_name)
+    render json: result
+  rescue StandardError => e
+    raise e unless Rails.env.development?
+    handle_error_in_development(e)
+  end
+
+  private
+
+  # Handle variables in form data, JSON body, or a blank value
+  def prepare_variables(variables_param)
+    case variables_param
+    when String
+      if variables_param.present?
+        JSON.parse(variables_param) || {}
+      else
+        {}
+      end
+    when Hash
+      variables_param
+    when ActionController::Parameters
+      variables_param.to_unsafe_hash # GraphQL-Ruby will validate name and type of incoming variables.
+    when nil
+      {}
+    else
+      raise ArgumentError, "Unexpected parameter: #{variables_param}"
+    end
+  end
+
+  def handle_error_in_development(e)
+    logger.error e.message
+    logger.error e.backtrace.join("\n")
+
+    render json: { errors: [{ message: e.message, backtrace: e.backtrace }], data: {} }, status: 500
+  end
+end
diff --git a/app/graphql/concerns/graphql_errors.rb b/app/graphql/concerns/graphql_errors.rb
new file mode 100644
index 00000000..92a24ec5
--- /dev/null
+++ b/app/graphql/concerns/graphql_errors.rb
@@ -0,0 +1,11 @@
+module GraphqlErrors
+  def formatted_errors(model)
+    model.errors.map do |error|
+      path = ["attributes", error.attribute.to_s.camelize(:lower)]
+      {
+        path: path,
+        message: error.message
+      }
+    end
+  end
+end
diff --git a/app/graphql/mutations/.keep b/app/graphql/mutations/.keep
new file mode 100644
index 00000000..e69de29b
diff --git a/app/graphql/mutations/base_mutation.rb b/app/graphql/mutations/base_mutation.rb
new file mode 100644
index 00000000..f733c75e
--- /dev/null
+++ b/app/graphql/mutations/base_mutation.rb
@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+module Mutations
+  class BaseMutation < GraphQL::Schema::Mutation
+    include GraphqlErrors
+
+    argument_class Types::BaseArgument
+    field_class Types::BaseField
+    object_class Types::BaseObject
+
+    def current_user
+      @context[:current_user]
+    end
+  end
+end
diff --git a/app/graphql/mutations/create_project.rb b/app/graphql/mutations/create_project.rb
new file mode 100644
index 00000000..e7421804
--- /dev/null
+++ b/app/graphql/mutations/create_project.rb
@@ -0,0 +1,13 @@
+module Mutations
+  class CreateProject < BaseMutation
+    argument :input, Types::Inputs::CreateProjectInput, required: true
+
+    type Types::Payloads::CreateProjectPayload
+
+    def resolve(input:)
+      result = Projects::Create.call(project_params: input.to_h, user: current_user)
+
+      result.to_h.merge(errors: formatted_errors(result.project))
+    end
+  end
+end
diff --git a/app/graphql/resolvers/base.rb b/app/graphql/resolvers/base.rb
new file mode 100644
index 00000000..e5162987
--- /dev/null
+++ b/app/graphql/resolvers/base.rb
@@ -0,0 +1,9 @@
+module Resolvers
+  class Base < GraphQL::Schema::Resolver
+    argument_class Types::BaseArgument
+
+    def current_user
+      @context[:current_user]
+    end
+  end
+end
diff --git a/app/graphql/resolvers/project.rb b/app/graphql/resolvers/project.rb
new file mode 100644
index 00000000..7e50ad5d
--- /dev/null
+++ b/app/graphql/resolvers/project.rb
@@ -0,0 +1,11 @@
+module Resolvers
+  class Project < Resolvers::Base
+    argument :id, ID, required: true
+
+    type Types::ProjectType, null: true
+
+    def resolve(**options)
+      ::Project.find_by(id: options[:id])
+    end
+  end
+end
diff --git a/app/graphql/resolvers/projects.rb b/app/graphql/resolvers/projects.rb
new file mode 100644
index 00000000..ab5d2eed
--- /dev/null
+++ b/app/graphql/resolvers/projects.rb
@@ -0,0 +1,9 @@
+module Resolvers
+  class Projects < Resolvers::Base
+    type [Types::ProjectType], null: false
+
+    def resolve(**_options)
+      ::Project.all
+    end
+  end
+end
diff --git a/app/graphql/task_tracker_itis_schema.rb b/app/graphql/task_tracker_itis_schema.rb
new file mode 100644
index 00000000..3c0798c8
--- /dev/null
+++ b/app/graphql/task_tracker_itis_schema.rb
@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+class TaskTrackerItisSchema < GraphQL::Schema
+  mutation(Types::MutationType)
+  query(Types::QueryType)
+
+  # For batch-loading (see https://graphql-ruby.org/dataloader/overview.html)
+  use GraphQL::Dataloader
+
+  # GraphQL-Ruby calls this when something goes wrong while running a query:
+  def self.type_error(err, context)
+    # if err.is_a?(GraphQL::InvalidNullError)
+    #   # report to your bug tracker here
+    #   return nil
+    # end
+    super
+  end
+
+  # Union and Interface Resolution
+  def self.resolve_type(abstract_type, obj, ctx)
+    # TODO: Implement this method
+    # to return the correct GraphQL object type for `obj`
+    raise(GraphQL::RequiredImplementationMissingError)
+  end
+
+  # Stop validating when it encounters this many errors:
+  validate_max_errors(100)
+
+  # Relay-style Object Identification:
+
+  # Return a string UUID for `object`
+  def self.id_from_object(object, type_definition, query_ctx)
+    # For example, use Rails' GlobalID library (https://github.com/rails/globalid):
+    object.to_gid_param
+  end
+
+  # Given a string UUID, find the object
+  def self.object_from_id(global_id, query_ctx)
+    # For example, use Rails' GlobalID library (https://github.com/rails/globalid):
+    GlobalID.find(global_id)
+  end
+end
diff --git a/app/graphql/types/.keep b/app/graphql/types/.keep
new file mode 100644
index 00000000..e69de29b
diff --git a/app/graphql/types/base_argument.rb b/app/graphql/types/base_argument.rb
new file mode 100644
index 00000000..2e2278c5
--- /dev/null
+++ b/app/graphql/types/base_argument.rb
@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+module Types
+  class BaseArgument < GraphQL::Schema::Argument
+  end
+end
diff --git a/app/graphql/types/base_connection.rb b/app/graphql/types/base_connection.rb
new file mode 100644
index 00000000..366c69e8
--- /dev/null
+++ b/app/graphql/types/base_connection.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module Types
+  class BaseConnection < Types::BaseObject
+    # add `nodes` and `pageInfo` fields, as well as `edge_type(...)` and `node_nullable(...)` overrides
+    include GraphQL::Types::Relay::ConnectionBehaviors
+  end
+end
diff --git a/app/graphql/types/base_edge.rb b/app/graphql/types/base_edge.rb
new file mode 100644
index 00000000..e0d2f79c
--- /dev/null
+++ b/app/graphql/types/base_edge.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module Types
+  class BaseEdge < Types::BaseObject
+    # add `node` and `cursor` fields, as well as `node_type(...)` override
+    include GraphQL::Types::Relay::EdgeBehaviors
+  end
+end
diff --git a/app/graphql/types/base_enum.rb b/app/graphql/types/base_enum.rb
new file mode 100644
index 00000000..cf43fea4
--- /dev/null
+++ b/app/graphql/types/base_enum.rb
@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+module Types
+  class BaseEnum < GraphQL::Schema::Enum
+  end
+end
diff --git a/app/graphql/types/base_field.rb b/app/graphql/types/base_field.rb
new file mode 100644
index 00000000..611eb056
--- /dev/null
+++ b/app/graphql/types/base_field.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+module Types
+  class BaseField < GraphQL::Schema::Field
+    argument_class Types::BaseArgument
+  end
+end
diff --git a/app/graphql/types/base_input_object.rb b/app/graphql/types/base_input_object.rb
new file mode 100644
index 00000000..27951132
--- /dev/null
+++ b/app/graphql/types/base_input_object.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+module Types
+  class BaseInputObject < GraphQL::Schema::InputObject
+    argument_class Types::BaseArgument
+  end
+end
diff --git a/app/graphql/types/base_interface.rb b/app/graphql/types/base_interface.rb
new file mode 100644
index 00000000..18899387
--- /dev/null
+++ b/app/graphql/types/base_interface.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+module Types
+  module BaseInterface
+    include GraphQL::Schema::Interface
+    edge_type_class(Types::BaseEdge)
+    connection_type_class(Types::BaseConnection)
+
+    field_class Types::BaseField
+  end
+end
diff --git a/app/graphql/types/base_object.rb b/app/graphql/types/base_object.rb
new file mode 100644
index 00000000..487af2f5
--- /dev/null
+++ b/app/graphql/types/base_object.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Types
+  class BaseObject < GraphQL::Schema::Object
+    edge_type_class(Types::BaseEdge)
+    connection_type_class(Types::BaseConnection)
+    field_class Types::BaseField
+  end
+end
diff --git a/app/graphql/types/base_scalar.rb b/app/graphql/types/base_scalar.rb
new file mode 100644
index 00000000..719bc808
--- /dev/null
+++ b/app/graphql/types/base_scalar.rb
@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+module Types
+  class BaseScalar < GraphQL::Schema::Scalar
+  end
+end
diff --git a/app/graphql/types/base_union.rb b/app/graphql/types/base_union.rb
new file mode 100644
index 00000000..95941696
--- /dev/null
+++ b/app/graphql/types/base_union.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module Types
+  class BaseUnion < GraphQL::Schema::Union
+    edge_type_class(Types::BaseEdge)
+    connection_type_class(Types::BaseConnection)
+  end
+end
diff --git a/app/graphql/types/inputs/create_project_input.rb b/app/graphql/types/inputs/create_project_input.rb
new file mode 100644
index 00000000..4f1d69fa
--- /dev/null
+++ b/app/graphql/types/inputs/create_project_input.rb
@@ -0,0 +1,8 @@
+module Types
+  module Inputs
+    class CreateProjectInput < Types::BaseInputObject
+      argument :name, String, required: true
+      argument :description, String, required: false
+    end
+  end
+end
diff --git a/app/graphql/types/mutation_type.rb b/app/graphql/types/mutation_type.rb
new file mode 100644
index 00000000..0b8c4060
--- /dev/null
+++ b/app/graphql/types/mutation_type.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+module Types
+  class MutationType < Types::BaseObject
+    field :create_project, mutation: Mutations::CreateProject
+  end
+end
diff --git a/app/graphql/types/node_type.rb b/app/graphql/types/node_type.rb
new file mode 100644
index 00000000..c71ec3ee
--- /dev/null
+++ b/app/graphql/types/node_type.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Types
+  module NodeType
+    include Types::BaseInterface
+    # Add the `id` field
+    include GraphQL::Types::Relay::NodeBehaviors
+  end
+end
diff --git a/app/graphql/types/payloads/create_project_payload.rb b/app/graphql/types/payloads/create_project_payload.rb
new file mode 100644
index 00000000..11f52716
--- /dev/null
+++ b/app/graphql/types/payloads/create_project_payload.rb
@@ -0,0 +1,8 @@
+module Types
+  module Payloads
+    class CreateProjectPayload < Types::BaseObject
+      field :project, ProjectType, null: true
+      field :errors, [Types::UserError], null: true
+    end
+  end
+end
diff --git a/app/graphql/types/project_type.rb b/app/graphql/types/project_type.rb
new file mode 100644
index 00000000..843e332f
--- /dev/null
+++ b/app/graphql/types/project_type.rb
@@ -0,0 +1,10 @@
+module Types
+  class ProjectType < Types::BaseObject
+    field :id, ID, null: false
+    field :name, String, null: false
+    field :description, String, null: false
+    field :created_at, GraphQL::Types::ISO8601DateTime, null: false
+    field :updated_at, GraphQL::Types::ISO8601DateTime, null: false
+    field :tasks, [TaskType], null: false
+  end
+end
diff --git a/app/graphql/types/query_type.rb b/app/graphql/types/query_type.rb
new file mode 100644
index 00000000..2d71e00c
--- /dev/null
+++ b/app/graphql/types/query_type.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module Types
+  class QueryType < Types::BaseObject
+    field :project, resolver: Resolvers::Project
+    field :projects, resolver: Resolvers::Projects
+  end
+end
diff --git a/app/graphql/types/task_status_type.rb b/app/graphql/types/task_status_type.rb
new file mode 100644
index 00000000..6dc53ed0
--- /dev/null
+++ b/app/graphql/types/task_status_type.rb
@@ -0,0 +1,7 @@
+module Types
+  class TaskStatusType < Types::BaseEnum
+    value "UNSTARTED", value: "unstarted", description: "Unstarted"
+    value "STARTED", value: "started", description: "Started"
+    value "FINISHED", value: "finished", description: "Finished"
+  end
+end
diff --git a/app/graphql/types/task_type.rb b/app/graphql/types/task_type.rb
new file mode 100644
index 00000000..9b5f169e
--- /dev/null
+++ b/app/graphql/types/task_type.rb
@@ -0,0 +1,13 @@
+module Types
+  class TaskType < Types::BaseObject
+    field :id, ID, null: false
+    field :name, String, null: false
+    field :description, String
+    field :deadline_at, GraphQL::Types::ISO8601DateTime
+    field :project_id, Integer, null: false
+    field :created_at, GraphQL::Types::ISO8601DateTime, null: false
+    field :updated_at, GraphQL::Types::ISO8601DateTime, null: false
+    field :status, TaskStatusType, null: false
+    field :project, ProjectType, null: false
+  end
+end
diff --git a/app/graphql/types/user_error.rb b/app/graphql/types/user_error.rb
new file mode 100644
index 00000000..49a5952d
--- /dev/null
+++ b/app/graphql/types/user_error.rb
@@ -0,0 +1,8 @@
+module Types
+  class UserError < Types::BaseObject
+    description "A user-readable error"
+
+    field :message, String, null: false, description: "A description of the error"
+    field :path, [String], description: "Which input value this error came from"
+  end
+end
diff --git a/bin/rspec b/bin/rspec
new file mode 100755
index 00000000..a6c78521
--- /dev/null
+++ b/bin/rspec
@@ -0,0 +1,29 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'rspec' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require "pathname"
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../../Gemfile",
+  Pathname.new(__FILE__).realpath)
+
+bundle_binstub = File.expand_path("../bundle", __FILE__)
+
+if File.file?(bundle_binstub)
+  if File.read(bundle_binstub, 300) =~ /This file was generated by Bundler/
+    load(bundle_binstub)
+  else
+    abort("Your `bin/bundle` was not generated by Bundler, so this binstub cannot run.
+Replace `bin/bundle` by running `bundle binstubs bundler --force`, then run this command again.")
+  end
+end
+
+require "rubygems"
+require "bundler/setup"
+
+load Gem.bin_path("rspec-core", "rspec")
diff --git a/config/routes.rb b/config/routes.rb
index 995a9fdf..6a51dae0 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -2,6 +2,9 @@
 
 Rails.application.routes.draw do
   mount Sidekiq::Web => "/sidekiq"
+  mount GraphiQL::Rails::Engine, at: "/graphiql", graphql_path: "/graphql" if Rails.env.development?
+
+  post "/graphql", to: "graphql#execute"
 
   namespace :api, defaults: { format: :json } do
     namespace :v1 do