Add Flipper for feature flag management

Author: samdev-7

Gemfile

@@ -103,3 +103,7 @@ gem "vite_rails", "~> 3.0"
 gem "inertia_rails-contrib", "~> 0.5.2"
 
 gem "countries", "~> 8.1"
+
+gem "flipper", "~> 1.3"
+gem "flipper-active_record", "~> 1.3"
+gem "flipper-ui", "~> 1.3"

Gemfile.lock

@@ -167,6 +167,18 @@ GEM
     ffi (1.17.3-arm64-darwin)
     ffi (1.17.3-x86_64-linux-gnu)
     ffi (1.17.3-x86_64-linux-musl)
+    flipper (1.4.0)
+      concurrent-ruby (< 2)
+    flipper-active_record (1.4.0)
+      activerecord (>= 4.2, < 9)
+      flipper (~> 1.4.0)
+    flipper-ui (1.4.0)
+      erubi (>= 1.0.0, < 2.0.0)
+      flipper (~> 1.4.0)
+      rack (>= 1.4, < 4)
+      rack-protection (>= 1.5.3, < 5.0.0)
+      rack-session (>= 1.0.2, < 3.0.0)
+      sanitize (< 8)
     fugit (1.12.1)
       et-orbi (~> 1.4)
       raabro (~> 1.4)
@@ -324,6 +336,10 @@ GEM
     rack (3.2.4)
     rack-attack (6.8.0)
       rack (>= 1.0, < 4)
+    rack-protection (4.2.1)
+      base64 (>= 0.1.0)
+      logger (>= 1.6.0)
+      rack (>= 3.0.0, < 4)
     rack-proxy (0.7.7)
       rack
     rack-session (2.1.1)
@@ -414,6 +430,9 @@ GEM
       logger
     rubyzip (3.2.2)
     safely_block (0.5.0)
+    sanitize (7.0.0)
+      crass (~> 1.0.2)
+      nokogiri (>= 1.16.8)
     securerandom (0.4.1)
     selenium-webdriver (4.40.0)
       base64 (~> 0.2)
@@ -536,6 +555,9 @@ DEPENDENCIES
   debug
   dotenv-rails
   faraday (~> 2.13)
+  flipper (~> 1.3)
+  flipper-active_record (~> 1.3)
+  flipper-ui (~> 1.3)
   geocoder
   image_processing (~> 1.2)
   inertia_rails (~> 3.10)

app/controllers/application_controller.rb

@@ -38,6 +38,10 @@ class ApplicationController < ActionController::Base
   inertia_share sign_out_path: -> { signout_path }
   inertia_share trial_session_path: -> { trial_session_path }
   inertia_share rsvp_path: -> { rsvp_path }
+  inertia_share features: -> { # Feature flags for the frontend
+    next {} unless current_user && !current_user.trial?
+    { collaborators: Flipper.enabled?(:collaborators, current_user) }
+  }
   inertia_share has_unread_mail: -> { # Drives the envelope badge on the path page
     next false unless current_user && !current_user.trial?
     MailMessage.visible_to(current_user)
@@ -66,6 +70,11 @@ def track_page_view
     end
   end
 
+  def collaborators_enabled?
+    current_user && Flipper.enabled?(:collaborators, current_user)
+  end
+  helper_method :collaborators_enabled? # Available in views/Inertia props
+
   def user_not_authorized
     flash[:alert] = "You are not authorized to perform this action."
     redirect_back(fallback_location: root_path)

app/frontend/types/index.ts

@@ -13,6 +13,10 @@ export interface User {
 
 export type FlashData = Record<string, string>
 
+export interface Features {
+  collaborators?: boolean
+}
+
 export interface SharedProps {
   auth: { user: User | null }
   flash: FlashData

app/models/user.rb

@@ -32,6 +32,7 @@
 class User < ApplicationRecord
   include Discardable
   include PgSearch::Model
+  include Flipper::Identifier # Enables per-user feature flags via Flipper
 
   has_paper_trail
 

config/initializers/flipper.rb

@@ -0,0 +1,5 @@
+require "flipper/adapters/active_record"
+
+Flipper.configure do |config|
+  config.adapter { Flipper::Adapters::ActiveRecord.new }
+end

config/routes.rb

@@ -118,6 +118,7 @@
 
   constraints Constraints::AdminConstraint.new do
     mount MissionControl::Jobs::Engine, at: "/jobs"
+    mount Flipper::UI.app(Flipper), at: "/flipper" # Feature flag dashboard — admin-only
 
     namespace :admin do
       resources :projects, only: [ :index, :show ]

db/migrate/20260318203634_create_flipper_tables.rb

@@ -0,0 +1,22 @@
+class CreateFlipperTables < ActiveRecord::Migration[8.1]
+  def up
+    create_table :flipper_features do |t|
+      t.string :key, null: false
+      t.timestamps null: false
+    end
+    add_index :flipper_features, :key, unique: true
+
+    create_table :flipper_gates do |t|
+      t.string :feature_key, null: false
+      t.string :key, null: false
+      t.text :value
+      t.timestamps null: false
+    end
+    add_index :flipper_gates, [ :feature_key, :key, :value ], unique: true, length: { value: 255 }
+  end
+
+  def down
+    drop_table :flipper_gates
+    drop_table :flipper_features
+  end
+end