diff --git a/.gitignore b/.gitignore
index 5ac8c1859..dbfa0f999 100644
--- a/.gitignore
+++ b/.gitignore
@@ -35,3 +35,6 @@ spec/examples.txt
 public/commit_id.txt
 vendor/cache/
 vendor/bundle/
+
+# Local docker-compose overrides (port mappings, volume mounts)
+docker-compose.override.yml
diff --git a/Gemfile b/Gemfile
index d1c112662..bfe0a21f1 100644
--- a/Gemfile
+++ b/Gemfile
@@ -16,7 +16,8 @@ gem 'dalli'
 gem 'deep_cloneable', '~> 3.2.0'
 gem 'devise', '~> 4.9'
 gem 'doorkeeper', '~> 5.8'
-gem 'doorkeeper-jwt', '~> 0.2.1'
+gem 'doorkeeper-jwt', '~> 0.4'
+gem 'doorkeeper-openid_connect', '~> 1.9'
 gem 'faraday', '~> 1.10'
 gem 'faraday-http-cache', '~> 2.4'
 gem 'faraday_middleware', '~> 1.2'
@@ -33,7 +34,7 @@ gem 'librato-metrics', '~> 2.1.2'
 gem 'lograge'
 gem 'mime-types'
 gem 'p3p', '~> 2.0'
-gem 'panoptes-client'
+gem 'panoptes-client', '~> 1.3'
 gem 'pg', '~> 1.4'
 gem 'pg_search'
 gem 'puma', '~> 6.4.3'
diff --git a/config/initializers/doorkeeper.rb b/config/initializers/doorkeeper.rb
index b6b576f6c..6d2489160 100644
--- a/config/initializers/doorkeeper.rb
+++ b/config/initializers/doorkeeper.rb
@@ -20,11 +20,12 @@ def self.force_secure_scheme?(host)
   orm :active_record
 
   use_refresh_token
+  use_pkce
 
   enable_application_owner :confirmation => true
 
   default_scopes  :public
-  optional_scopes *Doorkeeper::Panoptes::Scopes.optional
+  optional_scopes :openid, *Doorkeeper::Panoptes::Scopes.optional
 
   realm "Panoptes"
 
@@ -99,5 +100,5 @@ def self.force_secure_scheme?(host)
   secret_key_path Rails.root.join("config", "keys", "doorkeeper-jwt-#{Rails.env}.pem")
 
   # Sign using RSA SHA-512
-  encryption_method :rs512
+  signing_method :rs512
 end
diff --git a/config/initializers/doorkeeper_openid_connect.rb b/config/initializers/doorkeeper_openid_connect.rb
new file mode 100644
index 000000000..79a9e36fe
--- /dev/null
+++ b/config/initializers/doorkeeper_openid_connect.rb
@@ -0,0 +1,80 @@
+# frozen_string_literal: true
+
+# rubocop:disable Metrics/BlockLength
+Doorkeeper::OpenidConnect.configure do
+  issuer do |_resource_owner, _application|
+    if Rails.env.production?
+      'https://panoptes.zooniverse.org'
+    elsif Rails.env.staging? # rubocop:disable Rails/UnknownEnv
+      'https://panoptes-staging.zooniverse.org'
+    else
+      'http://localhost:3000'
+    end
+  end
+
+  # Use the same RSA key that Doorkeeper::JWT uses for signing access tokens.
+  signing_key lambda {
+    key_path = Rails.root.join('config', 'keys', "doorkeeper-jwt-#{Rails.env}.pem")
+    File.read(key_path)
+  }
+
+  signing_algorithm :rs512
+
+  # Resolve the resource owner (User) from a Doorkeeper access token.
+  resource_owner_from_access_token do |access_token|
+    User.find_by(id: access_token.resource_owner_id)
+  end
+
+  # Return the time the user last authenticated. Devise's current_sign_in_at tracks this.
+  auth_time_from_resource_owner do |resource_owner|
+    resource_owner.current_sign_in_at&.to_i
+  end
+
+  # Re-authentication handler. For the password grant flow used in development,
+  # the user is always freshly authenticated so we return them directly.
+  reauthenticate_resource_owner do |resource_owner, _return_to|
+    resource_owner
+  end
+
+  # OIDC subject identifier - unique, stable user ID.
+  subject do |resource_owner, _application|
+    resource_owner.id
+  end
+
+  subject_types_supported %i[public]
+
+  claims do
+    claim :login, scope: :openid do |resource_owner, _scopes, _access_token|
+      resource_owner.login
+    end
+
+    claim :name, scope: :openid do |resource_owner, _scopes, _access_token|
+      resource_owner.display_name
+    end
+
+    claim :credited_name, scope: :openid do |resource_owner, _scopes, _access_token|
+      resource_owner.credited_name
+    end
+
+    claim :email, scope: :openid, response: %i[id_token user_info] do |resource_owner, _scopes, _access_token|
+      resource_owner.email
+    end
+
+    claim :email_verified, scope: :openid, response: %i[id_token user_info] do |resource_owner, _scopes, _access_token|
+      resource_owner.confirmed_at.present?
+    end
+
+    claim :admin, scope: :openid do |resource_owner, _scopes, _access_token|
+      resource_owner.admin?
+    end
+
+    claim :created_at, scope: :openid do |resource_owner, _scopes, _access_token|
+      resource_owner.created_at.to_i
+    end
+
+    claim :zooniverse_id, scope: :openid do |resource_owner, _scopes, _access_token|
+      resource_owner.zooniverse_id
+    end
+  end
+end
+# rubocop:enable Metrics/BlockLength
diff --git a/config/routes.rb b/config/routes.rb
index 803a1fe5d..5dc908e1c 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -21,6 +21,8 @@
                 applications: 'applications'
   end
 
+  use_doorkeeper_openid_connect
+
   devise_for :users,
     controllers: { confirmations: 'confirmations', passwords: 'passwords' },
     skip: [ :sessions, :registrations ]
diff --git a/db/dev_seed_data/dev_seed_noninteractive.rb b/db/dev_seed_data/dev_seed_noninteractive.rb
new file mode 100644
index 000000000..aca6f3d30
--- /dev/null
+++ b/db/dev_seed_data/dev_seed_noninteractive.rb
@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+exit unless Rails.env.development?
+
+# Non-interactive version of dev_seed_data.rb for automated setup.
+# Uses a default password for the local admin user.
+
+DEFAULT_PASSWORD = 'password1234'
+
+Rails.logger.info "\n=== Panoptes Local Dev Setup (non-interactive) ==="
+
+# Setup admin user
+attrs = {
+  admin: true,
+  password: DEFAULT_PASSWORD,
+  login: 'zooniverse_admin',
+  email: 'no-reply@zooniverse.org'
+}
+admin = User.where(login: 'zooniverse_admin').first_or_create(attrs, &:build_identity_group)
+
+if admin.persisted?
+  Rails.logger.info "Admin user: #{admin.login} (email: #{admin.email})"
+  Rails.logger.info "Password:   #{DEFAULT_PASSWORD}"
+else
+  Rails.logger.info "ERROR: Failed to create admin user: #{admin.errors.full_messages.join(', ')}"
+  exit 1
+end
+
+# Setup Doorkeeper first-party OAuth application with openid scope
+app = Doorkeeper::Application.where(name: 'DevAppClient').first_or_create do |da|
+  da.owner = admin
+  da.name = 'DevAppClient'
+  da.redirect_uri = 'urn:ietf:wg:oauth:2.0:oob'
+  da.trust_level = 2
+  da.confidential = false
+  scopes = %i[public openid] | Doorkeeper::Panoptes::Scopes.optional
+  da.default_scope = scopes.map(&:to_s)
+end
+
+if app.persisted?
+  Rails.logger.info "OAuth app:  #{app.name}"
+  Rails.logger.info "Client ID:  #{app.uid}"
+  Rails.logger.info "\nAccess at: http://localhost:3000/oauth/applications"
+else
+  Rails.logger.info "ERROR: Failed to create OAuth app: #{app.errors.full_messages.join(', ')}"
+  exit 1
+end
+
+Rails.logger.info "\n=== Setup complete ==="
diff --git a/db/migrate/20260420200000_create_doorkeeper_openid_connect_tables.rb b/db/migrate/20260420200000_create_doorkeeper_openid_connect_tables.rb
new file mode 100644
index 000000000..cd47d754d
--- /dev/null
+++ b/db/migrate/20260420200000_create_doorkeeper_openid_connect_tables.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+class CreateDoorkeeperOpenidConnectTables < ActiveRecord::Migration[7.2]
+  disable_ddl_transaction!
+
+  def change
+    safety_assured do
+      # Schema defined by doorkeeper-openid_connect; timestamps not applicable.
+      create_table :oauth_openid_requests do |t| # rubocop:disable Rails/CreateTableWithTimestamps
+        t.references :access_grant, null: false, index: true
+        t.string :nonce, null: false
+      end
+
+      add_foreign_key(
+        :oauth_openid_requests,
+        :oauth_access_grants,
+        column: :access_grant_id,
+        on_delete: :cascade
+      )
+    end
+  end
+end
diff --git a/db/migrate/20260421100000_add_pkce_to_doorkeeper_access_grants.rb b/db/migrate/20260421100000_add_pkce_to_doorkeeper_access_grants.rb
new file mode 100644
index 000000000..c1c499cd8
--- /dev/null
+++ b/db/migrate/20260421100000_add_pkce_to_doorkeeper_access_grants.rb
@@ -0,0 +1,6 @@
+class AddPkceToDoorkeeperAccessGrants < ActiveRecord::Migration[6.1]
+  def change
+    add_column :oauth_access_grants, :code_challenge, :string, null: true
+    add_column :oauth_access_grants, :code_challenge_method, :string, null: true
+  end
+end
diff --git a/docker-compose.yml b/docker-compose.yml
index 7c63d0557..8c277eb9a 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -6,7 +6,7 @@ services:
       - "POSTGRES_USER=panoptes"
       - "POSTGRES_PASSWORD=panoptes"
     ports:
-      - "5432:5432"
+      - "${PG_PORT:-5432}:5432"
 
   redis:
     image: redis
@@ -21,7 +21,7 @@ services:
       - ./:/rails_app
       - gem_cache:/usr/local/bundle
     ports:
-      - "3000:3000"
+      - "${PANOPTES_PORT:-3000}:3000"
     environment:
       - "RAILS_ENV=development"
       - "DATABASE_URL=postgresql://panoptes:panoptes@pg"