diff --git a/.drone.yml b/.drone.yml
index 9567f82..efde520 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -2,6 +2,7 @@
 kind: pipeline
 type: docker
 name: default
+
 steps:
   - name: shellcheck
     image: koalaman/shellcheck-alpine
@@ -13,6 +14,7 @@ steps:
 kind: pipeline
 type: docker
 name: backend
+
 steps:
   - name: ameba
     image: veelenga/ameba
@@ -23,6 +25,25 @@ steps:
     image: boechat107/pgsanity
     commands:
       - pgsanity docker/backend/db/**/*.sql
+  - name: deps
+    image: crystallang/crystal:1.3-alpine
+    volumes:
+      - name: lib
+        path: /drone/src/docker/backend/lib
+    commands:
+      - cd docker/backend/
+      - shards install
+  - name: documentation
+    image: crystallang/crystal:1.3-alpine
+    volumes:
+      - name: lib
+        path: /drone/src/docker/backend/lib
+    commands:
+      - cd docker/backend/
+      - make docs
+    depends_on:
+      - ameba
+      - deps
   - name: build
     image: tmaier/docker-compose
     volumes:
@@ -34,10 +55,15 @@ steps:
     depends_on:
       - ameba
       - pgsanity
+      - documentation
+
 volumes:
+  - name: lib
+    temp: {}
   - name: dockersock
     host:
       path: /var/run/docker.sock
+
 depends_on:
   - default
 
@@ -45,6 +71,7 @@ depends_on:
 kind: pipeline
 type: docker
 name: frontend
+
 steps:
   - name: prettier
     image: elnebuloso/prettier
@@ -61,9 +88,11 @@ steps:
       - docker-compose build --build-arg BUILD_ENV=development frontend
     depends_on:
       - prettier
+
 volumes:
   - name: dockersock
     host:
       path: /var/run/docker.sock
+
 depends_on:
   - default
diff --git a/.example.env b/.example.env
index 63efdce..c38cd7f 100644
--- a/.example.env
+++ b/.example.env
@@ -23,6 +23,6 @@ BACKEND_SMTP_PASSWORD=
 BACKEND_LDAP_HOST=
 BACKEND_LDAP_PORT=
 BACKEND_LDAP_BASE_DN=
+BACKEND_LDAP_BASE_USER_DN=
 BACKEND_BIND_DN=
 BACKEND_BIND_PASSWORD=
-BACKEND_LDAP_USER_DN=
diff --git a/README.md b/README.md
index 4825a1c..ce73aae 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,7 @@
 # mentorenwahl
 
 A fullstack application for assigning mentors to students based on their whishes.
+
+# Documentation
+
+To build the documentation, run `make docs` in `docker/backend/`.
diff --git a/docker-compose.yml b/docker-compose.yml
index 7a5a5cf..71ba61b 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -74,9 +74,9 @@ services:
       BACKEND_LDAP_HOST: ${BACKEND_LDAP_HOST}
       BACKEND_LDAP_PORT: ${BACKEND_LDAP_PORT}
       BACKEND_LDAP_BASE_DN: ${BACKEND_LDAP_BASE_DN}
+      BACKEND_LDAP_BASE_USER_DN: ${BACKEND_LDAP_BASE_USER_DN}
       BACKEND_LDAP_BIND_DN: ${BACKEND_LDAP_BIND_DN}
       BACKEND_LDAP_BIND_PASSWORD: ${BACKEND_LDAP_BIND_PASSWORD}
-      BACKEND_LDAP_USER_DN: ${BACKEND_LDAP_USER_DN}
 
   frontend:
     build:
diff --git a/docker/backend/Dockerfile b/docker/backend/Dockerfile
index 0063221..ffbf2b5 100644
--- a/docker/backend/Dockerfile
+++ b/docker/backend/Dockerfile
@@ -9,12 +9,13 @@ ARG BUILD_ENV
 WORKDIR /app/backend
 COPY --from=deps /app/shard.yml /app/shard.lock ./
 COPY --from=deps /app/lib ./lib
+COPY ./Makefile ./Makefile
 COPY ./LICENSE ./LICENSE
 COPY ./src ./src
 RUN if [ "${BUILD_ENV}" = "development" ]; then \
-  time shards build -Ddevelopment --static --verbose -s -p -t; \
+  make dev; \
   else \
-  time shards build --static --release --no-debug --verbose -s -p -t; \
+  make; \
   fi
 
 FROM alpine as runner
diff --git a/docker/backend/Makefile b/docker/backend/Makefile
new file mode 100644
index 0000000..c27b736
--- /dev/null
+++ b/docker/backend/Makefile
@@ -0,0 +1,12 @@
+.PHONY: all dev prod docs
+
+all: prod
+
+dev:
+	shards build -Ddevelopment --static --verbose -s -p -t
+
+prod:
+	shards build --static --release --no-debug --verbose -s -p -t
+
+docs:
+	crystal docs --project-name "Mentorenwahl Backend" -D granite_docs
diff --git a/docker/backend/src/backend.cr b/docker/backend/src/backend.cr
index 417e3ef..4295edf 100644
--- a/docker/backend/src/backend.cr
+++ b/docker/backend/src/backend.cr
@@ -1 +1,5 @@
 require "./backend/*"
+
+# Base module
+module Backend
+end
diff --git a/docker/backend/src/backend/api.cr b/docker/backend/src/backend/api.cr
index f2c0573..34e5d53 100644
--- a/docker/backend/src/backend/api.cr
+++ b/docker/backend/src/backend/api.cr
@@ -1 +1,5 @@
 require "./api/*"
+
+# Api module
+module Backend::Api
+end
diff --git a/docker/backend/src/backend/api/auth.cr b/docker/backend/src/backend/api/auth.cr
index 533e303..6d2fd0f 100644
--- a/docker/backend/src/backend/api/auth.cr
+++ b/docker/backend/src/backend/api/auth.cr
@@ -2,28 +2,36 @@ require "jwt"
 
 module Backend
   module Api
+    # Authorization and authentication utilities
     module Auth
       extend self
 
+      # Bearer token header
       BEARER = "Bearer "
 
+      # Creates raw JWT token
+      #
+      # WARNING: Always use a wrapper for this method
       private def create_jwt(data, expiration : Int) : String
         JWT.encode({"data" => data.to_h, "exp" => expiration}, Backend.config.api.jwt_secret, JWT::Algorithm::HS256)
       end
 
-      def create_user_jwt(user_id : Int, expiration : Int) : String
-        create_jwt({user_id: user_id}, expiration)
-      end
-
+      # Decodes JWT token
       def decode_jwt(jwt : String) : JSON::Any
         JWT.decode(jwt, Backend.config.api.jwt_secret, JWT::Algorithm::HS256)[0]
       end
 
+      # :ditto:
       def decode_jwt?(jwt : String) : JSON::Any?
         decode_jwt(jwt)
       rescue
         nil
       end
+
+      # Creates JWT token for user
+      def create_user_jwt(user_id : Int, expiration : Int) : String
+        create_jwt({user_id: user_id}, expiration)
+      end
     end
   end
 end
diff --git a/docker/backend/src/backend/api/context.cr b/docker/backend/src/backend/api/context.cr
index 73d6675..b935eca 100644
--- a/docker/backend/src/backend/api/context.cr
+++ b/docker/backend/src/backend/api/context.cr
@@ -4,10 +4,18 @@ require "granite"
 
 module Backend
   module Api
+    # GraphQL request context class
     class Context < GraphQL::Context
+      # Authenticated user
       getter user : Db::User?
+
+      # User is admin
       getter admin : Bool?
+
+      # User's role
       getter role : Schema::UserRole?
+
+      # User's external object
       getter external : (Db::Teacher | Db::Student)?
 
       def initialize(request : HTTP::Request, max_complexity : Int32? = nil)
@@ -36,26 +44,31 @@ module Backend
         end
       end
 
+      # User is authenticated
       def authenticated? : Bool
         !!@user
       end
 
+      # :ditto:
       def authenticated! : Bool
         raise "Not authenticated" unless authenticated?
 
         true
       end
 
+      # User is admin
       def admin? : Bool
         authenticated? && !!@admin
       end
 
+      # :ditto:
       def admin! : Bool
         raise "Invalid permissions" unless admin?
 
         true
       end
 
+      # User's is one of *roles*
       def role?(external = true, *roles : Schema::UserRole) : Bool
         return false unless authenticated?
 
@@ -75,51 +88,32 @@ module Backend
         false
       end
 
+      # :ditto:
       def role!(external = true, *roles : Schema::UserRole) : Bool
         raise "Invalid permissions" unless role? external, *roles
 
         true
       end
 
+      # User is teacher
       def teacher?(external = false) : Bool
         role? external, Schema::UserRole::Teacher
       end
 
+      # :ditto:
       def teacher! : Bool
         role! external, Schema::UserRole::Teacher
       end
 
+      # User is student
       def student?(external = false) : Bool
         role? external, Schema::UserRole::Student
       end
 
+      # :ditto:
       def student! : Bool
         role! external, Schema::UserRole::Student
       end
-
-      # private macro role_check(*roles)
-      #   {% for role in roles %}
-      #     {% name = role.names.last.underscore %}
-      #       def {{ name }}?(external = true) : Bool
-      #         role? external, {{ role }}
-      #       end
-
-      #       def {{ name }}!(external = true) : Bool
-      #         role! external, {{ role }}
-      #       end
-      #   {% end %}
-      # end
-
-      # role_check Schema::UserRole::Teacher, Schema::UserRole::Student
-
-      # def self.db_eq_role?(external : Granite::Base, role : Schema::UserRole) : Bool
-      #   role == case external
-      #   when Db::Teacher
-      #     Schema::UserRole::Teacher
-      #   when Db::Student
-      #     Schema::UserRole::Student
-      #   end
-      # end
     end
   end
 end
diff --git a/docker/backend/src/backend/api/run.cr b/docker/backend/src/backend/api/run.cr
index 5dc71bc..4b1a733 100644
--- a/docker/backend/src/backend/api/run.cr
+++ b/docker/backend/src/backend/api/run.cr
@@ -4,6 +4,7 @@ module Backend
   module Api
     extend self
 
+    # Runs API
     def run : Nil
       WebServer.new.run
     end
diff --git a/docker/backend/src/backend/api/schema.cr b/docker/backend/src/backend/api/schema.cr
index 9468dda..106f396 100644
--- a/docker/backend/src/backend/api/schema.cr
+++ b/docker/backend/src/backend/api/schema.cr
@@ -5,7 +5,9 @@ require "./schema/*"
 
 module Backend
   module Api
+    # GraphQL schema definitions
     module Schema
+      # Compiled GraphQL schema
       SCHEMA = GraphQL::Schema.new(Query.new, Mutation.new)
     end
   end
diff --git a/docker/backend/src/backend/api/schema/helpers.cr b/docker/backend/src/backend/api/schema/helpers.cr
index aace3b7..736d050 100644
--- a/docker/backend/src/backend/api/schema/helpers.cr
+++ b/docker/backend/src/backend/api/schema/helpers.cr
@@ -1,8 +1,11 @@
 module Backend
   module Api
     module Schema
+      # Schema helper macros
       module Helpers
+        # Object helpers
         module ObjectMacros
+          # Defines field property and GraphQL specific getter
           macro field(type)
             property {{ type.var }} {% if type.value %} = {{ type.value }}{% end %}
 
@@ -13,7 +16,9 @@ module Backend
           end
         end
 
+        # DB model leverage helpers
         module ObjectDbInit
+          # Defines a DB model specific initializer
           macro db_init(type)
             def initialize(obj : {{ type }})
               initialize(obj.id.not_nil!)
@@ -21,12 +26,16 @@ module Backend
           end
         end
 
+        # DB model finder helpers
         module ObjectFinders
+          # Defines finder
           macro finders(type)
+            # Finds object by ID
             def find : {{ type }}?
               {{ type }}.find(@id)
             end
 
+            # :ditto:
             def find! : {{ type }}
               obj = find
               raise "#{{{ type }}} not found" unless obj
@@ -36,8 +45,12 @@ module Backend
           end
         end
 
+        # DB model field helpers
         module DbObject
+          # Defines DB model field helper functions
           macro db_object(type)
+            {% space_name = type.names.last.underscore.gsub(/_/, " ").capitalize %}
+
             include ::Backend::Api::Schema::Helpers::ObjectDbInit
             include ::Backend::Api::Schema::Helpers::ObjectFinders
 
@@ -54,6 +67,7 @@ module Backend
             end
 
             @[GraphQL::Field]
+            # {{ space_name }}'s ID
             def id : Int32
               @id
             end
diff --git a/docker/backend/src/backend/api/schema/mutation.cr b/docker/backend/src/backend/api/schema/mutation.cr
index 219d931..4557f75 100644
--- a/docker/backend/src/backend/api/schema/mutation.cr
+++ b/docker/backend/src/backend/api/schema/mutation.cr
@@ -6,6 +6,7 @@ module Backend
       @[GraphQL::Object]
       class Mutation < GraphQL::BaseMutation
         @[GraphQL::Field]
+        # Logs in as *username* with credential *password*
         def login(username : String, password : String) : LoginPayload
           raise "Auth failed" if username.empty? || password.empty?
 
@@ -22,6 +23,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # Creates user
         def create_user(context : Context, input : UserCreateInput, check_ldap : Bool = true) : User
           context.admin!
 
@@ -36,6 +38,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # Deletes user by ID
         def delete_user(context : Context, id : Int32) : Int32
           context.admin!
 
@@ -46,6 +49,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # Sends all unregistered teachers a registration email
         def send_teachers_registration_email(context : Context) : Bool
           context.admin!
 
@@ -55,6 +59,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # Creates teacher
         def create_teacher(context : Context, input : TeacherCreateInput) : Teacher
           context.admin!
 
@@ -63,6 +68,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # Deletes teacher by ID
         def delete_teacher(context : Context, id : Int32) : Int32
           context.admin!
 
@@ -73,6 +79,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # Self register as teacher
         def register_teacher(context : Context, input : TeacherInput) : Teacher
           context.teacher? external: false
 
@@ -82,6 +89,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # Creates student
         def create_student(context : Context, input : StudentCreateInput) : Student
           context.admin!
 
@@ -93,6 +101,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # Deletes student by ID
         def delete_student(context : Context, id : Int32) : Int32
           context.admin!
 
@@ -103,6 +112,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # Creates vote for authenticated user's student
         def create_vote(context : Context, input : VoteCreateInput) : Vote
           context.student!
 
diff --git a/docker/backend/src/backend/api/schema/query.cr b/docker/backend/src/backend/api/schema/query.cr
index 2ee95af..7b3a8cc 100644
--- a/docker/backend/src/backend/api/schema/query.cr
+++ b/docker/backend/src/backend/api/schema/query.cr
@@ -4,11 +4,13 @@ module Backend
       @[GraphQL::Object]
       class Query < GraphQL::BaseQuery
         @[GraphQL::Field]
+        # Retuns true
         def ok : Bool
           true
         end
 
         @[GraphQL::Field]
+        # Current authenticated user
         def me(context : Context) : User
           context.authenticated!
 
@@ -16,6 +18,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # User by ID
         def user(context : Context, id : Int32) : User
           context.admin!
 
@@ -23,6 +26,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # All users
         def users(context : Context) : Array(User)
           context.admin!
 
@@ -30,6 +34,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # All admins
         def admins(context : Context) : Array(User)
           context.admin!
 
@@ -37,16 +42,19 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # Teacher by ID
         def teacher(id : Int32) : Teacher
           Teacher.new(Db::Teacher.find!(id))
         end
 
         @[GraphQL::Field]
+        # All teachers
         def teachers : Array(Teacher)
           Db::Teacher.all.map { |teacher| Teacher.new(teacher) }
         end
 
         @[GraphQL::Field]
+        # Student by ID
         def student(context : Context, id : Int32) : Student
           context.admin!
 
@@ -54,6 +62,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # All students
         def students(context : Context) : Array(Student)
           context.admin!
 
@@ -61,6 +70,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # Vote by ID
         def vote(context : Context, id : Int32) : Vote
           context.admin!
 
@@ -68,6 +78,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # All votes
         def votes(context : Context) : Array(Vote)
           context.admin!
 
diff --git a/docker/backend/src/backend/api/schema/student.cr b/docker/backend/src/backend/api/schema/student.cr
index cf851d2..5c5b6d2 100644
--- a/docker/backend/src/backend/api/schema/student.cr
+++ b/docker/backend/src/backend/api/schema/student.cr
@@ -2,31 +2,35 @@ module Backend
   module Api
     module Schema
       @[GraphQL::Object]
+      # Student model
       class Student < GraphQL::BaseObject
         include Helpers::DbObject
 
         db_object Db::Student
 
         @[GraphQL::Field]
+        # Student's user
         def user : User
           User.new(find!.user)
         end
 
         @[GraphQL::Field]
+        # Student at SKIF
         def skif : Bool
           find!.skif
         end
 
         @[GraphQL::Field]
+        # Student's vote
         def vote : Vote?
-          vote = find!.vote
-
-          Vote.new(vote) if vote
+          find!.vote.try { |v| Vote.new(v) }
         end
       end
 
       @[GraphQL::InputObject]
+      # Student base input
       class StudentInput < GraphQL::BaseInputObject
+        # Student at SKIF
         getter skif
 
         @[GraphQL::Field]
@@ -35,7 +39,9 @@ module Backend
       end
 
       @[GraphQL::InputObject]
+      # Student creation input
       class StudentCreateInput < StudentInput
+        # Student's user ID
         getter user_id
 
         @[GraphQL::Field]
diff --git a/docker/backend/src/backend/api/schema/teacher.cr b/docker/backend/src/backend/api/schema/teacher.cr
index 5ebc88a..b4e47b2 100644
--- a/docker/backend/src/backend/api/schema/teacher.cr
+++ b/docker/backend/src/backend/api/schema/teacher.cr
@@ -2,30 +2,38 @@ module Backend
   module Api
     module Schema
       @[GraphQL::Object]
+      # Teacher model
       class Teacher < GraphQL::BaseObject
         include Helpers::DbObject
 
         db_object Db::Teacher
 
         @[GraphQL::Field]
+        # Teacher's user
         def user : User
           User.new(find!.user)
         end
 
         @[GraphQL::Field]
+        # Teacher's max students
         def max_students : Int32
           find!.max_students
         end
 
         @[GraphQL::Field]
+        # Teacher is at SKIF
         def skif : Bool
           find!.skif
         end
       end
 
       @[GraphQL::InputObject]
+      # Base teacher input
       class TeacherInput < GraphQL::BaseInputObject
+        # Teacher's max students
         getter max_students
+
+        # Teacher at SKIF
         getter skif
 
         @[GraphQL::Field]
@@ -34,7 +42,9 @@ module Backend
       end
 
       @[GraphQL::InputObject]
+      # Teacher creation input
       class TeacherCreateInput < TeacherInput
+        # Teacher's user ID
         getter user_id
 
         @[GraphQL::Field]
diff --git a/docker/backend/src/backend/api/schema/teacher_vote.cr b/docker/backend/src/backend/api/schema/teacher_vote.cr
index cb54697..bcf61e0 100644
--- a/docker/backend/src/backend/api/schema/teacher_vote.cr
+++ b/docker/backend/src/backend/api/schema/teacher_vote.cr
@@ -2,26 +2,35 @@ module Backend
   module Api
     module Schema
       @[GraphQL::Object]
+      # Teacher vote model
       class TeacherVote < GraphQL::BaseObject
         include Helpers::DbObject
 
         db_object Db::TeacherVote
 
         @[GraphQL::Field]
+        # Voted teacher
         def teacher : Teacher
           Teacher.new(find!.teacher.not_nil!)
         end
 
         @[GraphQL::Field]
+        # Teacher vote's priority
         def priority : Int32
           find!.priority
         end
       end
 
       @[GraphQL::InputObject]
+      # Teacher vote creation input
       class TeacherVoteCreateInput < GraphQL::BaseInputObject
+        # Teacher vote's vote ID
         getter vote_id
+
+        # Teacher vote's teacher ID
         getter teacher_id
+
+        # Teacher vote's priority
         getter priority
 
         @[GraphQL::Field]
diff --git a/docker/backend/src/backend/api/schema/user.cr b/docker/backend/src/backend/api/schema/user.cr
index 017f173..7cd9646 100644
--- a/docker/backend/src/backend/api/schema/user.cr
+++ b/docker/backend/src/backend/api/schema/user.cr
@@ -2,42 +2,50 @@ module Backend
   module Api
     module Schema
       @[GraphQL::Object]
+      # User model
       class User < GraphQL::BaseObject
         include Helpers::DbObject
 
         db_object Db::User
 
         @[GraphQL::Field]
+        # User's first name
         def firstname : String
           find!.firstname
         end
 
         @[GraphQL::Field]
+        # User's last name
         def lastname : String
           find!.lastname
         end
 
         @[GraphQL::Field]
+        # User's full name
         def name : String
           find!.name
         end
 
         @[GraphQL::Field]
+        # User's LDAP username
         def username : String
           find!.username
         end
 
         @[GraphQL::Field]
+        # User's email
         def email : String
           find!.email
         end
 
         @[GraphQL::Field]
+        # User is admin
         def admin : Bool
           find!.admin
         end
 
         @[GraphQL::Field]
+        # User's role
         def role : UserRole
           role = Db::UserRole.parse(find!.role)
           case role
@@ -51,6 +59,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # User's external ID
         def external_id : Int32?
           case Db::UserRole.parse(find!.role)
           when .teacher?
@@ -63,6 +72,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # User's external teacher object
         def teacher : Teacher?
           teacher = find!.teacher
           if teacher
@@ -71,6 +81,7 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # User's external student object
         def student : Student?
           student = find!.student
           if student
@@ -80,6 +91,7 @@ module Backend
       end
 
       @[GraphQL::InputObject]
+      # User creation input
       class UserCreateInput < GraphQL::BaseInputObject
         getter username
         getter role
@@ -93,8 +105,12 @@ module Backend
       end
 
       @[GraphQL::Object]
+      # Login payload returned after successful login
       class LoginPayload < GraphQL::BaseObject
+        # Logged in user
         property user
+
+        # JWT token
         property token
 
         def initialize(
@@ -104,16 +120,19 @@ module Backend
         end
 
         @[GraphQL::Field]
+        # Logged in user
         def user : User
           @user
         end
 
         @[GraphQL::Field]
+        # Raw bearer token
         def token : String
           @token
         end
 
         @[GraphQL::Field]
+        # Ready to use bearer token
         def bearer : String
           Auth::BEARER + @token
         end
diff --git a/docker/backend/src/backend/api/schema/user_role.cr b/docker/backend/src/backend/api/schema/user_role.cr
index 3e469b1..f828688 100644
--- a/docker/backend/src/backend/api/schema/user_role.cr
+++ b/docker/backend/src/backend/api/schema/user_role.cr
@@ -2,6 +2,7 @@ module Backend
   module Api
     module Schema
       @[GraphQL::Enum]
+      # Possible roles of a user
       enum UserRole
         Teacher
         Student
diff --git a/docker/backend/src/backend/api/schema/vote.cr b/docker/backend/src/backend/api/schema/vote.cr
index 9a69c31..cd22b8b 100644
--- a/docker/backend/src/backend/api/schema/vote.cr
+++ b/docker/backend/src/backend/api/schema/vote.cr
@@ -2,24 +2,29 @@ module Backend
   module Api
     module Schema
       @[GraphQL::Object]
+      # Vote model
       class Vote < GraphQL::BaseObject
         include Helpers::DbObject
 
         db_object Db::Vote
 
         @[GraphQL::Field]
+        # Student who voted
         def student : Student
           Student.new(find!.student)
         end
 
         @[GraphQL::Field]
+        # Teacher votes for student
         def teacher_votes : Array(TeacherVote)
           find!.teacher_votes.map { |tv| TeacherVote.new(tv) }
         end
       end
 
       @[GraphQL::InputObject]
+      # Vote creation input
       class VoteCreateInput < GraphQL::BaseInputObject
+        # Teacher IDs student votes for
         getter teacher_ids
 
         @[GraphQL::Field]
diff --git a/docker/backend/src/backend/api/service.cr b/docker/backend/src/backend/api/service.cr
index bc5d9c1..7f1affa 100644
--- a/docker/backend/src/backend/api/service.cr
+++ b/docker/backend/src/backend/api/service.cr
@@ -1,5 +1,6 @@
 module Backend
   module Api
+    # Api service
     SERVICE = ->do
       Log.info { "Starting Api service..." }
       run
diff --git a/docker/backend/src/backend/api/webserver.cr b/docker/backend/src/backend/api/webserver.cr
index 8ce1f5d..ff4d0be 100644
--- a/docker/backend/src/backend/api/webserver.cr
+++ b/docker/backend/src/backend/api/webserver.cr
@@ -4,11 +4,16 @@ require "json"
 
 module Backend
   module Api
+    # Api webserver
     class WebServer
       include Router
 
+      # GraphQL playground HTML code
+      #
+      # NOTE: Is minified in production
       GRAPHQL_PLAYGROUND = {{ flag?(:development) ? read_file("#{__DIR__}/playground.html") : run("./macros/minify_html.cr", read_file("#{__DIR__}/playground.html")).stringify }}
 
+      # GraphQL request data serializer
       struct GraphQLQueryData
         include JSON::Serializable
 
@@ -17,9 +22,10 @@ module Backend
         property operation_name : String?
       end
 
+      # "Draws" (creates) routes
       def draw_routes : Nil
         # enable graphql playground when in development mode or explicitly enabled
-        if Backend.config.api.graphql_playground_fully_enabled
+        if Backend.config.api.graphql_playground_fully_enabled?
           Log.info { "GraphQL playground enabled" }
 
           get "/" do |context|
@@ -47,6 +53,7 @@ module Backend
         end
       end
 
+      # Runs the webserver with according middleware
       def run : Nil
         draw_routes
 
diff --git a/docker/backend/src/backend/config.cr b/docker/backend/src/backend/config.cr
index fa3dfd2..236111a 100644
--- a/docker/backend/src/backend/config.cr
+++ b/docker/backend/src/backend/config.cr
@@ -6,90 +6,145 @@ module Backend
 
   @@config = Config.new(ENV, prefix: "BACKEND")
 
+  # Global configuration
   def config : Config
     @@config
   end
 
+  # Environment based configuration class
   class Config
     include EnvConfig
 
+    # Types of environments program can compiled for / with
     enum BuildEnv
-      Development
       Production
+      Development
     end
 
-    def development : Bool
-      {{ flag?(:development) }}
-    end
-
-    def production : Bool
-      !development
-    end
-
+    # Type of environment program is running in
     def build_env : BuildEnv
-      development ? BuildEnv::Development : BuildEnv::Production
+      {{ flag?(:development) }} ? BuildEnv::Development : BuildEnv::Production
     end
 
+    # Production mode
+    #
+    # `true` if the build environment is `BuildEnv::Development`
+    def production? : Bool
+      build_env.production?
+    end
+
+    # Development mode
+    #
+    # `true` if the build environment is `BuildEnv::Production`
+    def development? : Bool
+      build_env.development?
+    end
+
+    # Base URL of application
     getter url : String
 
     @[EnvConfig::Setting(key: "api")]
+    # Configuration for `Api`
     getter api : ApiConfig
 
     @[EnvConfig::Setting(key: "worker")]
+    # Configuration for `Worker`
     getter worker : WorkerConfig
 
     @[EnvConfig::Setting(key: "smtp")]
+    # Configuration for `Mailers`
     getter smtp : SmtpConfig
 
     @[EnvConfig::Setting(key: "db")]
+    # Configuration for `Db`
     getter db : DbConfig
 
     @[EnvConfig::Setting(key: "ldap")]
+    # Configuration for `Ldap`
     getter ldap : LdapConfig
 
+    # Configuration for `Api`
     class ApiConfig
       include EnvConfig
 
+      # GraphQL playground enable
       getter graphql_playground : Bool
+
+      # JWT signing key
       getter jwt_secret : String
 
-      def graphql_playground_fully_enabled : Bool
-        Backend.config.development || graphql_playground
+      # Helper method for enabling GraphQL playground
+      #
+      # Returns `true` if `Config#development?` or `#graphql_playground` are
+      def graphql_playground_fully_enabled? : Bool
+        Backend.config.development? || graphql_playground
       end
     end
 
+    # Configuration for `Worker`
     class WorkerConfig
       include EnvConfig
 
+      # Redis URL
       getter redis_url : String
     end
 
+    # Configuration for `Mailers`
     class SmtpConfig
       include EnvConfig
 
+      # SMTP host HELO
+      #
+      # NOTE: HELOs are [FQDNs](https://en.wikipedia.org/wiki/Fully_qualified_domain_name), so this should be a domain name
       getter helo : String
+
+      # SMTP hostname
       getter host : String
+
+      # SMTP port
       getter port : Int32
+
+      # Name to send from
       getter name : String
+
+      # SMTP username
       getter username : String
+
+      # SMTP password
       getter password : String
     end
 
+    # Configuration for `Db`
     class DbConfig
       include EnvConfig
 
+      # Database URL
       getter url : String
     end
 
+    # Configuration for `Ldap`
     class LdapConfig
       include EnvConfig
 
+      # LDAP hostname
       getter host : String
+
+      # LDAP port
       getter port : Int32
+
+      # LDAP base DN
       getter base_dn : String
+
+      # LDAP user base DN
+      getter base_user_dn : String
+
+      # LDAP bind DN
+      #
+      # NOTE: This is the DN to search with
       getter bind_dn : String
+
+      # LDAP bind password
       getter bind_password : String
-      getter user_dn : String
     end
   end
 end
diff --git a/docker/backend/src/backend/db.cr b/docker/backend/src/backend/db.cr
index 68e2f1e..25f65cf 100644
--- a/docker/backend/src/backend/db.cr
+++ b/docker/backend/src/backend/db.cr
@@ -4,6 +4,7 @@ require "granite/adapter/pg"
 require "./db/*"
 
 module Backend
+  # Database model definitions
   module Db
     Granite::Connections << Granite::Adapter::Pg.new(name: "pg", url: Backend.config.db.url)
   end
diff --git a/docker/backend/src/backend/db/student.cr b/docker/backend/src/backend/db/student.cr
index 97d49a8..f8809a3 100644
--- a/docker/backend/src/backend/db/student.cr
+++ b/docker/backend/src/backend/db/student.cr
@@ -1,12 +1,16 @@
 module Backend
   module Db
+    # Student model
     class Student < Granite::Base
       table students
 
       belongs_to :user
       has_one :vote
 
+      # Student's ID
       column id : Int64, primary: true
+
+      # Student is at SKIF
       column skif : Bool
     end
   end
diff --git a/docker/backend/src/backend/db/teacher.cr b/docker/backend/src/backend/db/teacher.cr
index b1516ec..87b4e4d 100644
--- a/docker/backend/src/backend/db/teacher.cr
+++ b/docker/backend/src/backend/db/teacher.cr
@@ -1,13 +1,19 @@
 module Backend
   module Db
+    # Teacher model
     class Teacher < Granite::Base
       table teachers
 
       belongs_to :user
       has_many teacher_votes : TeacherVote
 
+      # Teacher's ID
       column id : Int64, primary: true
+
+      # Teacher's max students count
       column max_students : Int32
+
+      # Teacher is at SKIF
       column skif : Bool
     end
   end
diff --git a/docker/backend/src/backend/db/teacher_vote.cr b/docker/backend/src/backend/db/teacher_vote.cr
index 8a7a32b..90459fa 100644
--- a/docker/backend/src/backend/db/teacher_vote.cr
+++ b/docker/backend/src/backend/db/teacher_vote.cr
@@ -1,12 +1,16 @@
 module Backend
   module Db
+    # Teacher vote model
     class TeacherVote < Granite::Base
       table teacher_votes
 
       belongs_to :vote
       belongs_to :teacher
 
+      # Teacher votes's ID
       column id : Int64, primary: true
+
+      # Teacher vote's priority
       column priority : Int32
 
       validate :teacher, "must be vote unique" do |teacher_vote|
diff --git a/docker/backend/src/backend/db/user.cr b/docker/backend/src/backend/db/user.cr
index a5ddb2d..013308b 100644
--- a/docker/backend/src/backend/db/user.cr
+++ b/docker/backend/src/backend/db/user.cr
@@ -1,28 +1,40 @@
 module Backend
   module Db
+    # User model
     class User < Granite::Base
       table users
 
       has_one :teacher
       has_one :student
 
+      # User's ID
       column id : Int64, primary: true
+
+      # User's LDAP username
       column username : String
+
+      # User's role
       column role : String
+
+      # User is admin
       column admin : Bool = false
 
+      # User's first name
       def firstname : String
         Ldap.user(Ldap.uid(@username.not_nil!)).first["givenName"].first
       end
 
+      # User's last name
       def lastname : String
         Ldap.user(Ldap.uid(@username.not_nil!)).first["sn"].first
       end
 
+      # User's full name
       def name : String
         Ldap.user(Ldap.uid(@username.not_nil!)).first["cn"].first
       end
 
+      # User's email
       def email : String
         Ldap.user(Ldap.uid(@username.not_nil!)).first["mail"].first
       end
diff --git a/docker/backend/src/backend/db/user_role.cr b/docker/backend/src/backend/db/user_role.cr
index 1250b63..d847b98 100644
--- a/docker/backend/src/backend/db/user_role.cr
+++ b/docker/backend/src/backend/db/user_role.cr
@@ -1,5 +1,6 @@
 module Backend
   module Db
+    # Possible roles a user can have
     enum UserRole
       Teacher
       Student
diff --git a/docker/backend/src/backend/ldap.cr b/docker/backend/src/backend/ldap.cr
index 74b53f4..6740312 100644
--- a/docker/backend/src/backend/ldap.cr
+++ b/docker/backend/src/backend/ldap.cr
@@ -3,27 +3,35 @@ require "socket"
 require "ldap_escape"
 
 module Backend
+  # Provides LDAP utility functions
   module Ldap
     extend self
 
+    # Creates a new LDAP connection
     def create_client : LDAP::Client
       LDAP::Client.new(TCPSocket.new(Backend.config.ldap.host, Backend.config.ldap.port))
     end
 
+    # Constructs a CN DN from a username
     def cn(username : String) : String
       "cn=#{LdapEscape.dn(username)},#{Backend.config.ldap.user_dn}"
     end
 
+    # Constructs a UID DN from a username
     def uid(uid : String) : String
-      "uid=#{LdapEscape.dn(uid)},#{Backend.config.ldap.user_dn}"
+      "uid=#{LdapEscape.dn(uid)},#{Backend.config.ldap.base_user_dn}"
     end
 
+    # Queries the LDAP server for a user
+    #
+    # NOTE: Returns a hash of the user's attributes
     def user(dn : String) : Array(Hash(String, Array(String)))
       create_client
         .authenticate(Backend.config.ldap.bind_dn, Backend.config.ldap.bind_password)
         .search(base: dn)
     end
 
+    # Checks if credentials are valid
     def authenticate?(dn : String, password : String) : Bool
       !!create_client.authenticate(dn, password)
     rescue LDAP::Client::AuthError
diff --git a/docker/backend/src/backend/mailers.cr b/docker/backend/src/backend/mailers.cr
index 050ca25..2f74881 100644
--- a/docker/backend/src/backend/mailers.cr
+++ b/docker/backend/src/backend/mailers.cr
@@ -5,6 +5,7 @@ require "kilt"
 require "./mailers/*"
 
 module Backend
+  # Mailer definitions
   module Mailers
     Quartz.config do |config|
       config.smtp_enabled = true
diff --git a/docker/backend/src/backend/mailers/teacher_registration_mailer.cr b/docker/backend/src/backend/mailers/teacher_registration_mailer.cr
index 12e8113..4f99dde 100644
--- a/docker/backend/src/backend/mailers/teacher_registration_mailer.cr
+++ b/docker/backend/src/backend/mailers/teacher_registration_mailer.cr
@@ -1,5 +1,6 @@
 module Backend
   module Mailers
+    # Sends teacher a polite registration mail to ask if they may input their data
     class TeacherRegistrationMailer < Quartz::Composer
       def sender : Quartz::Message::Address
         address email: Backend.config.smtp.username, name: Backend.config.smtp.name
diff --git a/docker/backend/src/backend/run.cr b/docker/backend/src/backend/run.cr
index 4865f43..3d2d3b9 100644
--- a/docker/backend/src/backend/run.cr
+++ b/docker/backend/src/backend/run.cr
@@ -1,6 +1,7 @@
 module Backend
   extend self
 
+  # Runs backend services
   def run : Nil
     {% if flag?(:development) %}
       Log.warn { "Backend is running in development mode! Do not use this in production!" }
diff --git a/docker/backend/src/backend/services.cr b/docker/backend/src/backend/services.cr
index 0cbfb1e..43b2421 100644
--- a/docker/backend/src/backend/services.cr
+++ b/docker/backend/src/backend/services.cr
@@ -1,4 +1,5 @@
 module Backend
+  # Backend services to be included in the application
   SERVICES = [
     Api::SERVICE,
     Worker::SERVICE,
diff --git a/docker/backend/src/backend/worker.cr b/docker/backend/src/backend/worker.cr
index 4395346..7b3a1ff 100644
--- a/docker/backend/src/backend/worker.cr
+++ b/docker/backend/src/backend/worker.cr
@@ -1,8 +1,5 @@
 require "mosquito"
 
-module Mosquito::Serializers::Array
-end
-
 module Mosquito::Serializers::Granite
   macro serialize_granite_model(klass)
     {% method_suffix = klass.resolve.stringify.underscore.gsub(/::/, "__").id %}
@@ -21,6 +18,7 @@ end
 require "./worker/*"
 
 module Backend
+  # Worker module
   module Worker
     Mosquito.configure do |settings|
       settings.redis_url = Backend.config.worker.redis_url
diff --git a/docker/backend/src/backend/worker/jobs.cr b/docker/backend/src/backend/worker/jobs.cr
index db7012a..df74540 100644
--- a/docker/backend/src/backend/worker/jobs.cr
+++ b/docker/backend/src/backend/worker/jobs.cr
@@ -1 +1,5 @@
 require "./jobs/*"
+
+# Job definitions
+module Backend::Worker::Jobs
+end
diff --git a/docker/backend/src/backend/worker/jobs/send_teachers_registration_email_job.cr b/docker/backend/src/backend/worker/jobs/send_teachers_registration_email_job.cr
index 2137bf2..6da07b2 100644
--- a/docker/backend/src/backend/worker/jobs/send_teachers_registration_email_job.cr
+++ b/docker/backend/src/backend/worker/jobs/send_teachers_registration_email_job.cr
@@ -3,7 +3,9 @@ require "../../db/user"
 module Backend
   module Worker
     module Jobs
+      # Sends all unregistered teachers a polite registration mail to ask if they may input their data
       class SendTeachersRegistrationEmailJob < Mosquito::QueuedJob
+        # :ditto:
         def perform : Nil
           users = Db::User.where(role: Db::UserRole::Teacher.to_s, teacher_id: nil)
           count = users.count.run.as(Int64).to_i
diff --git a/docker/backend/src/backend/worker/run.cr b/docker/backend/src/backend/worker/run.cr
index 6941c91..de57b6c 100644
--- a/docker/backend/src/backend/worker/run.cr
+++ b/docker/backend/src/backend/worker/run.cr
@@ -2,6 +2,7 @@ module Backend
   module Worker
     extend self
 
+    # Runs the worker
     def run : Nil
       Mosquito::Runner.start
     end
diff --git a/docker/backend/src/backend/worker/service.cr b/docker/backend/src/backend/worker/service.cr
index d9cc71e..fc9c0bc 100644
--- a/docker/backend/src/backend/worker/service.cr
+++ b/docker/backend/src/backend/worker/service.cr
@@ -1,5 +1,6 @@
 module Backend
   module Worker
+    # Worker service
     SERVICE = ->do
       Log.info { "Starting worker service..." }
       run