feat: signup nudge email sequence for members without a chapter

app/controllers/check_ins_controller.rb

@@ -102,9 +102,9 @@ def find_invitation
 
   def find_or_create_invitation(role)
     if @check_in_target.is_a?(Event)
-      Invitation.create_or_find_by(event: @check_in_target, member: current_user, role: role)
+      Invitation.create_or_find_by(event: @check_in_target, member: current_user, role:)
     else
-      WorkshopInvitation.create_or_find_by(workshop: @check_in_target, member: current_user, role: role)
+      WorkshopInvitation.create_or_find_by(workshop: @check_in_target, member: current_user, role:)
     end
   end
 

app/jobs/send_signup_nudge_email_job.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+class SendSignupNudgeEmailJob < ApplicationJob
+  queue_as :default
+
+  def perform
+    SignupNudgeEmailService.send_nudges
+  end
+end

app/mailers/member_mailer.rb

@@ -2,7 +2,27 @@ class MemberMailer < ApplicationMailer
   include EmailHeaderHelper
   include EmailDelivery
 
-  after_deliver :log_sent_email, only: [:chaser]
+  after_deliver :log_sent_email, only: %i[chaser signup_nudge signup_nudge_followup]
+
+  # Placeholder copy — replace with Kimberley's copy (issue #2384) before merge.
+  def signup_nudge
+    @member = params[:member]
+    subject = 'Pick a codebar chapter'
+
+    mail_to_member(@member, subject, 'hello@codebar.io') do |format|
+      format.html { render 'signup_nudge' }
+    end
+  end
+
+  # Placeholder copy — replace with Kimberley's copy (issue #2384) before merge.
+  def signup_nudge_followup
+    @member = params[:member]
+    subject = 'Still thinking about codebar?'
+
+    mail_to_member(@member, subject, 'hello@codebar.io') do |format|
+      format.html { render 'signup_nudge_followup' }
+    end
+  end
 
   def chaser
     @member = params[:member]

app/services/signup_nudge_email_service.rb

@@ -0,0 +1,42 @@
+class SignupNudgeEmailService
+  NUDGE = 'signup_nudge'.freeze
+  FOLLOWUP = 'signup_nudge_followup'.freeze
+
+  def self.send_nudges
+    send_signup_nudge
+    send_signup_nudge_followup
+  end
+
+  def self.send_signup_nudge
+    Member.not_banned
+          .where(created_at: nudge_window)
+          .merge(unemailed(NUDGE))
+          .merge(never_subscribed)
+          .find_each { |member| MemberMailer.with(member:).signup_nudge.deliver_later }
+  end
+
+  def self.send_signup_nudge_followup
+    Member.not_banned
+          .joins(:member_email_deliveries)
+          .where(member_email_deliveries: { email_type: NUDGE, created_at: ..1.month.ago })
+          .merge(unemailed(FOLLOWUP))
+          .merge(never_subscribed)
+          .distinct
+          .find_each { |member| MemberMailer.with(member:).signup_nudge_followup.deliver_later }
+  end
+
+  def self.unemailed(email_type)
+    Member.where.not(id: MemberEmailDelivery.where(email_type:).select(:member_id))
+  end
+
+  def self.never_subscribed
+    Member.where.not(id: Subscription.select(:member_id))
+  end
+
+  def self.nudge_window
+    14.days.ago.beginning_of_day..7.days.ago.end_of_day
+  end
+
+  private_class_method :send_signup_nudge, :send_signup_nudge_followup, :unemailed, :never_subscribed,
+                       :nudge_window
+end

app/views/member_mailer/signup_nudge.html.haml

@@ -0,0 +1,13 @@
+/ Placeholder copy — replace with Kimberley's copy (issue #2384) before merge.
+%h1 Hi #{@member.name},
+
+%p
+  Thanks for signing up to codebar! You’ve created your account, but you haven’t picked a chapter yet.
+
+%p
+  Head to your dashboard, choose the chapter closest to you, and subscribe as a student or a coach — then we can start inviting you to workshops.
+
+%p
+  #{"-- "}
+%br
+The codebar team

app/views/member_mailer/signup_nudge_followup.html.haml

@@ -0,0 +1,13 @@
+/ Placeholder copy — replace with Kimberley's copy (issue #2384) before merge.
+%h1 Hi #{@member.name},
+
+%p
+  A little while ago we nudged you about picking a codebar chapter — you still haven’t subscribed, so we wanted to check in once more.
+
+%p
+  It only takes a minute: choose your nearest chapter, subscribe, and you’ll hear about every upcoming workshop there.
+
+%p
+  #{"-- "}
+%br
+The codebar team

docs/plans/2026-08-31-signup-nudge-email-sequence-plan.md

@@ -0,0 +1,81 @@
+---
+type: feat
+origin: none
+issue: codebar/planner#2384
+artifact_readiness: implementation-ready
+---
+
+# Signup nudge email sequence (issue #2384)
+
+Automated emails to members who signed up via the website but never subscribed to a chapter: a nudge 7–14 days after signup and a follow-up one month later, then the sequence ends. Built on the typed `member_email_deliveries` log shipped in #2832 (`email_type` column + unique index on `(member_id, email_type)`).
+
+## Key Technical Decisions
+
+- **Shared typed log as sequence state** — `session-settled: user-approved` (class: user-approved; rejected alternative: dedicated `signup_nudges` table; also rejected: boolean flags on `members`). Stage eligibility is derived from `member_email_deliveries` rows; no new state store.
+- **Stage 1 window 7–14 days after signup** — `session-settled: user-approved` (class: user-approved; rejected alternatives: strict one-day window, rolling `<= 7 days` window). Wide enough to absorb scheduler gaps, narrow enough to exclude the historical never-subscribed backlog from the day of deploy.
+- **Stage 2 anchored to stage 1's send time** — `session-settled: user-approved` (class: user-approved; rejected alternative: fixed member age). Follow-up lands exactly one month after the nudge regardless of when a run picked up the member.
+- **Audience includes abandoned signups** — `session-settled: user-directed` (class: user-directed; rejected alternative: `accepted_toc`-only). Members who never completed signup receive the nudge.
+- **Dedupe is delivery-confirmed** — rows are written by the `EmailDelivery` concern after delivery; there is no pre-enqueue stamping. Rejected alternative: stamp-before-enqueue (at-most-once) — loses the "lost nudge" self-healing within the stage-1 window.
+- **No `member_email_deliveries` exclusion coupling** — the chaser's exclusion is already scoped to `email_type: 'chaser'` (#2832); nudge rows cannot suppress chaser emails.
+
+## Implementation Units
+
+### U1 — Mailer actions and views
+
+- **Goal:** two member-facing emails that opt into the typed delivery log.
+- **Files:**
+  - Modify `app/mailers/member_mailer.rb`
+  - Create `app/views/member_mailer/signup_nudge.html.haml`
+  - Create `app/views/member_mailer/signup_nudge_followup.html.haml`
+- **Approach:**
+  - `def signup_nudge` — subject and copy TBD (placeholder until copy arrives from Kimberley); `mail_to_member(member, subject, 'hello@codebar.io')`; rendered via `signup_nudge.html.haml`.
+  - `def signup_nudge_followup` — same shape, second subject/copy.
+  - `after_deliver :log_sent_email, only: [:chaser, :signup_nudge, :signup_nudge_followup]`.
+- **Test scenarios:**
+  - Each action renders headers (to/from) and non-empty body containing its distinctive copy.
+  - Delivery creates a `MemberEmailDelivery` row with the action's `email_type`.
+
+### U2 — Sequence service
+
+- **Goal:** one service computes both stages' eligible members per daily run and sends.
+- **Files:**
+  - Create `app/services/signup_nudge_email_service.rb`
+- **Approach:**
+  - `def self.send_nudges`
+  - Stage 1 (nudge): `Member.not_banned` where `created_at` falls on the 7..14-days-ago window, `where.not(id: Subscription.select(:member_id))`, `where.not(id: MemberEmailDelivery.where(email_type: 'signup_nudge').select(:member_id))`; `MemberMailer.with(member:).signup_nudge.deliver_later` per member.
+  - Stage 2 (follow-up): `Member.not_banned` with a `signup_nudge` row `created_at <= 1.month.ago`, no `signup_nudge_followup` row, `where.not(id: Subscription.select(:member_id))`; `MemberMailer.with(member:).signup_nudge_followup.deliver_later`.
+  - No `accepted_toc` filter (abandoned signups included). No `unsubscribed` filter (nothing sets it; the chaser ignores it too).
+- **Test scenarios:**
+  - Sends nudge to a member created 10 days ago with no subscription; follow-up to a member whose nudge row is 6 weeks old.
+  - Skips: subscribed members, banned members, members with the stage's row already present, members younger than 7 days, members older than 14 days without a nudge row, follow-up for a member whose nudge row is 3 weeks old, follow-up for a member with no nudge row.
+  - Terminal state: a member with both rows receives nothing from either stage.
+
+### U3 — Job and rake task
+
+- **Goal:** the daily entry point, mirroring the chaser's wiring.
+- **Files:**
+  - Create `app/jobs/send_signup_nudge_email_job.rb`
+  - Modify `lib/tasks/chaser.rake`
+- **Approach:** `SendSignupNudgeEmailJob` (queue `:default`) calls `SignupNudgeEmailService.send_nudges`; rake task `chaser:signup_nudges` enqueues the job; the namespace description is updated to cover both emails.
+- **Test scenarios:**
+  - The rake task enqueues the job (existing chaser rake-task spec pattern).
+
+### U4 — Ops handoff
+
+- **Goal:** the sequence actually runs daily in production.
+- **Files:** none (dashboard-side).
+- **Approach:** PR description carries an ops note: add a Heroku Scheduler entry `rake chaser:signup_nudges` (daily), same as the existing `rake chaser:three_months` entry; without it the feature ships dark.
+- **Test scenarios:** none.
+
+## Verification
+
+- `make test` (parallel RSpec) green; new specs for U1–U3; existing `three_month_email_service` specs unaffected (chaser exclusion already typed).
+- Manual letter-opener check of both emails in development.
+- After merge: confirm the first scheduled run creates `signup_nudge` rows for the current 7–14-day cohort. Owner: Morgan.
+
+## Risks & Dependencies
+
+- **Copy dependency:** both subjects/bodies are placeholders until Kimberley provides copy via Slack (per the issue). The PR can be reviewed and held; copy lands as a follow-up commit before merge.
+- **Volume:** cohorts are 0–3 members/day (verified against the production dump). A stage-1 catch-up run is bounded by the 8 daily cohorts in the 7–14-day window (≤ ~24 emails); a stage-2 catch-up after a long outage is bounded by the accumulated `signup_nudge` population rather than the two-week window.
+- **Deploy-time boundary:** members older than 14 days at merge never enter the sequence — accepted, bounded.
+- **Edge cases accepted:** a member who subscribes and unsubscribes within the month re-enters stage 2; a member whose stage-1 send failed (e.g. invalid email → `SkippedEmail`) gets no stage-1 row and therefore no stage 2 (under-send bias).

lib/tasks/chaser.rake

@@ -1,7 +1,11 @@
 namespace :chaser do
   desc "Send emails to users who've not attended in a while"
-
   task three_months: :environment do
     SendThreeMonthEmailJob.perform_later
   end
+
+  desc 'Send emails to new members who have not subscribed to a chapter'
+  task signup_nudges: :environment do
+    SendSignupNudgeEmailJob.perform_later
+  end
 end

spec/controllers/check_ins_controller_spec.rb

@@ -35,7 +35,7 @@
 
       it 'creates an invitation with source=check_in' do
         post :create, params: { code: event.check_in_code, role: 'Student' }
-        invitation = Invitation.find_by(event: event, member: member)
+        invitation = Invitation.find_by(event:, member:)
         expect(invitation.source).to eq(InvitationConcerns::SOURCE_CHECK_IN)
         expect(invitation.attending).to be true
         expect(invitation.verified).to be true
@@ -56,28 +56,28 @@
 
       it 'ignores unpermitted parameters' do
         post :create, params: { code: event.check_in_code, role: 'Student', hacker_field: 'malicious' }
-        invitation = Invitation.find_by(event: event, member: member)
+        invitation = Invitation.find_by(event:, member:)
         expect(invitation.source).to eq(InvitationConcerns::SOURCE_CHECK_IN)
         expect(response).to redirect_to(check_in_e_confirm_path(code: event.check_in_code))
       end
 
       it 'redirects to confirm when already checked in' do
-        invitation = Fabricate(:invitation, event: event, member: member, role: 'Student', attending: true, verified: true)
+        invitation = Fabricate(:invitation, event:, member:, role: 'Student', attending: true, verified: true)
         post :create, params: { code: event.check_in_code, role: 'Student' }
         expect(response).to redirect_to(check_in_e_confirm_path(code: event.check_in_code))
         expect(Invitation.find(invitation.id).verified).to be true
       end
 
       it 'rejects selecting a different role than the existing invitation' do
-        Fabricate(:invitation, event: event, member: member, role: 'Student')
+        Fabricate(:invitation, event:, member:, role: 'Student')
         post :create, params: { code: event.check_in_code, role: 'Coach' }
         expect(response).to redirect_to(check_in_e_path(code: event.check_in_code))
         expect(flash[:alert]).to include('Student')
       end
 
       it 'rejects check-in when the role is at capacity' do
         event.update!(student_spaces: 1)
-        Fabricate(:invitation, event: event, member: Fabricate(:member), role: 'Student',
+        Fabricate(:invitation, event:, member: Fabricate(:member), role: 'Student',
                                attending: true, verified: true)
         post :create, params: { code: event.check_in_code, role: 'Student' }
         expect(response).to redirect_to(check_in_e_path(code: event.check_in_code))
@@ -89,7 +89,7 @@
                              date_and_time: Time.zone.now - 30.minutes,
                              ends_at: Time.zone.now + 30.minutes)
         post :create, params: { code: workshop.check_in_code, role: 'Student' }
-        invitation = WorkshopInvitation.find_by(workshop: workshop, member: member)
+        invitation = WorkshopInvitation.find_by(workshop:, member:)
         expect(invitation.source).to eq(InvitationConcerns::SOURCE_CHECK_IN)
         expect(invitation.attending).to be true
         expect(invitation.attended).to be true
@@ -101,7 +101,7 @@
         workshop = Fabricate(:workshop,
                              date_and_time: Time.zone.now - 30.minutes,
                              ends_at: Time.zone.now + 30.minutes)
-        invitation = Fabricate(:workshop_invitation, workshop: workshop, member: member, role: 'Student')
+        invitation = Fabricate(:workshop_invitation, workshop:, member:, role: 'Student')
         WaitingList.add(invitation)
         post :create, params: { code: workshop.check_in_code, role: 'Student' }
         expect(response).to redirect_to(check_in_w_path(code: workshop.check_in_code))

spec/lib/tasks/chaser_rake_spec.rb

@@ -0,0 +1,13 @@
+RSpec.describe 'rake chaser:signup_nudges', type: :task do
+  it 'preloads the Rails environment' do
+    expect(task.prerequisites).to include 'environment'
+  end
+
+  it 'enqueues the signup nudge email job' do
+    allow(SendSignupNudgeEmailJob).to receive(:perform_later)
+
+    task.invoke
+
+    expect(SendSignupNudgeEmailJob).to have_received(:perform_later)
+  end
+end

spec/mailers/member_mailer_spec.rb

@@ -196,4 +196,42 @@
       end.to change(MemberEmailDelivery, :count).by(1)
     end
   end
+
+  describe 'signup nudge' do
+    let(:mail) { described_class.with(member:).signup_nudge.deliver_now }
+
+    it 'renders the headers' do
+      expect(mail.subject).to eq('Pick a codebar chapter')
+      expect(mail.to).to eq([member.email])
+      expect(mail.from).to eq(['hello@codebar.io'])
+    end
+
+    it 'renders the body' do
+      expect(mail.body.encoded).to match('Head to your dashboard')
+    end
+
+    it 'logs with its own email_type' do
+      expect { mail }
+        .to change { MemberEmailDelivery.where(member:, email_type: 'signup_nudge').count }.by(1)
+    end
+  end
+
+  describe 'signup nudge follow-up' do
+    let(:mail) { described_class.with(member:).signup_nudge_followup.deliver_now }
+
+    it 'renders the headers' do
+      expect(mail.subject).to eq('Still thinking about codebar?')
+      expect(mail.to).to eq([member.email])
+      expect(mail.from).to eq(['hello@codebar.io'])
+    end
+
+    it 'renders the body' do
+      expect(mail.body.encoded).to match('we nudged you')
+    end
+
+    it 'logs with its own email_type' do
+      expect { mail }
+        .to change { MemberEmailDelivery.where(member:, email_type: 'signup_nudge_followup').count }.by(1)
+    end
+  end
 end