hackclub · skyfallwastaken · May 21, 2026 · May 21, 2026 · May 21, 2026 · May 21, 2026
diff --git a/Gemfile b/Gemfile
@@ -41,6 +41,9 @@ gem "sentry-rails"
 
 gem "good_job"
 
+# Bitmask flag column on AR models — used for User#event_participation.
+gem "active_flag"
+
 # Slack client
 gem "slack-ruby-client"
 

diff --git a/Gemfile.lock b/Gemfile.lock
@@ -47,6 +47,8 @@ GEM
       erubi (~> 1.11)
       rails-dom-testing (~> 2.2)
       rails-html-sanitizer (~> 1.6)
+    active_flag (2.1.1)
+      activerecord (>= 5)
     activejob (8.1.3)
       activesupport (= 8.1.3)
       globalid (>= 0.3.6)
@@ -659,6 +661,7 @@ PLATFORMS
   x86_64-linux-musl
 
 DEPENDENCIES
+  active_flag
   activerecord-import
   autotuner (~> 1.0)
   aws-sdk-s3

diff --git a/app/controllers/inertia_controller.rb b/app/controllers/inertia_controller.rb
@@ -148,7 +148,9 @@ def inertia_nav_current_user
       country_code: current_user.country_code,
       country_name: country&.common_name,
       streak_days: current_user.streak_days,
-      admin_level: current_user.admin_level
+      admin_level: current_user.admin_level,
+      created_at: current_user.created_at&.iso8601,
+      event_participation: current_user.event_participation_backfilled? ? current_user.event_participation.to_a.map(&:to_s) : nil
     }
   end
 

diff --git a/app/javascript/pages/Home/signedIn/IntervalSelect.svelte b/app/javascript/pages/Home/signedIn/IntervalSelect.svelte
@@ -1,8 +1,18 @@
 <script lang="ts">
   import { Popover, RadioGroup } from "bits-ui";
+  import { page } from "@inertiajs/svelte";
   import Button from "../../../components/Button.svelte";
+  import eventsConfig from "$config/events.json";
 
-  const INTERVALS = [
+  type EventConfig = {
+    human_name: string;
+    starts_at: string;
+    ends_at: string;
+    timezone: string;
+  };
+  const EVENT_RANGES = eventsConfig as Record<string, EventConfig>;
+
+  const STANDARD_INTERVALS = [
     { key: "today", label: "Today" },
     { key: "yesterday", label: "Yesterday" },
     { key: "this_week", label: "This Week" },
@@ -11,13 +21,16 @@
     { key: "last_30_days", label: "Last 30 Days" },
     { key: "this_year", label: "This Year" },
     { key: "last_12_months", label: "Last 12 Months" },
-    { key: "flavortown", label: "Flavortown" },
-    { key: "summer_of_making", label: "Summer of Making" },
-    { key: "high_seas", label: "High Seas" },
-    { key: "low_skies", label: "Low Skies" },
-    { key: "scrapyard", label: "Scrapyard Global" },
+  ];
+  const EVENT_INTERVALS = Object.entries(EVENT_RANGES).map(([key, cfg]) => ({
+    key,
+    label: cfg.human_name,
+  }));
+  const INTERVALS = [
+    ...STANDARD_INTERVALS,
+    ...EVENT_INTERVALS,
     { key: "", label: "All Time" },
-  ] as const;
+  ];
 
   let {
     selected,
@@ -31,6 +44,29 @@
     onchange: (interval: string, from: string, to: string) => void;
   } = $props();
 
+  const currentUser = page.props.layout.nav.current_user!;
+  const userCreatedAt = Date.parse(currentUser.created_at!);
+  // null = user hasn't been backfilled yet, so we can't trust the bitmap
+  const participated = currentUser.event_participation
+    ? new Set(currentUser.event_participation)
+    : null;
+
+  const visibleIntervals = $derived(
+    INTERVALS.filter((interval) => {
+      const range = EVENT_RANGES[interval.key];
+      if (!range) return true;
+      if (interval.key === selected) return true;
+      const endsAt = Date.parse(range.ends_at);
+      // Ended event + backfilled: show only if the user actually participated.
+      // Otherwise (active/future event, or not-yet-backfilled user) fall back
+      // to the cheap "did the user exist before the event ended" check.
+      if (endsAt < Date.now() && participated) {
+        return participated.has(interval.key);
+      }
+      return userCreatedAt <= endsAt;
+    }),
+  );
+
   let open = $state(false);
   let customFrom = $state("");
   let customTo = $state("");
@@ -132,7 +168,7 @@
             onValueChange={selectInterval}
             class="flex flex-col gap-1 overflow-hidden"
           >
-            {#each INTERVALS as interval}
+            {#each visibleIntervals as interval (interval.key)}
               <RadioGroup.Item
                 value={interval.key}
                 class="flex w-full items-center rounded-md px-3 py-2 text-left text-sm text-muted outline-none transition-all duration-150 hover:bg-surface-100/60 hover:text-surface-content data-[highlighted]:bg-surface-100/70 data-[state=checked]:bg-primary/12 data-[state=checked]:text-surface-content"

diff --git a/app/javascript/types/index.ts b/app/javascript/types/index.ts
@@ -3,7 +3,9 @@ export type FlashData = {
   alert?: string;
 };
 
-export type SharedProps = {};
+export type SharedProps = {
+  layout: LayoutProps;
+};
 
 export type NavLink = {
   label: string;
@@ -29,6 +31,9 @@ export type NavCurrentUser = {
   country_name?: string | null;
   streak_days?: number | null;
   admin_level: AdminLevel;
+  created_at?: string | null;
+  // null until the user has been backfilled — fall back to created_at then.
+  event_participation: string[] | null;
 };
 
 export type LayoutNav = {

diff --git a/app/models/concerns/time_range_filterable.rb b/app/models/concerns/time_range_filterable.rb
@@ -1,7 +1,7 @@
 module TimeRangeFilterable
   extend ActiveSupport::Concern
 
-  RANGES = {
+  STANDARD_RANGES = {
     today: {
       human_name: "Today",
       calculate: -> { Time.current.beginning_of_day..Time.current.end_of_day }
@@ -33,63 +33,32 @@ module TimeRangeFilterable
     last_12_months: {
       human_name: "Last 12 Months",
       calculate: -> { (Time.current - 12.months).beginning_of_day..Time.current.end_of_day }
-    },
-    flavortown: {
-      human_name: "Flavortown",
-      calculate: -> {
-        timezone = "America/New_York"
-        Time.use_zone(timezone) do
-          from = Time.parse("2025-12-15").beginning_of_day
-          to = Time.parse("2026-04-30").end_of_day
-          from.beginning_of_day..to.end_of_day
-        end
-      }
-    },
-    summer_of_making: {
-      human_name: "Summer of Making",
-      calculate: -> {
-        timezone = "America/New_York"
-        Time.use_zone(timezone) do
-          from = Time.parse("2025-06-16").beginning_of_day
-          to = Time.parse("2025-09-30").end_of_day
-          from.beginning_of_day..to.end_of_day
-        end
-      }
-    },
-    high_seas: {
-      human_name: "High Seas",
-      calculate: -> {
-        timezone = "America/New_York"
-        Time.use_zone(timezone) do
-          from = Time.parse("2024-10-30").beginning_of_day
-          to = Time.parse("2025-01-31").end_of_day
-          from.beginning_of_day..to.end_of_day
-        end
-      }
-    },
-    low_skies: {
-      human_name: "Low Skies",
-      calculate: -> {
-        timezone = "America/New_York"
-        Time.use_zone(timezone) do
-          from = Time.parse("2024-10-3").beginning_of_day
-          to = Time.parse("2025-01-12").end_of_day
-          from.beginning_of_day..to.end_of_day
-        end
-      }
-    },
-    scrapyard: {
-      human_name: "Scrapyard Global",
+    }
+  }.freeze
+
+  EVENTS_CONFIG_PATH = Rails.root.join("config", "events.json").freeze
+
+  EVENT_DEFINITIONS = JSON.parse(File.read(EVENTS_CONFIG_PATH)).freeze
+
+  # mahad says: NEVER remove entries from the events JSON
+  # if you need to get rid of an event, add a retired flag or something
+  EVENT_KEYS = EVENT_DEFINITIONS.keys.sort.map(&:to_sym).freeze
+
+  EVENT_RANGES = EVENT_DEFINITIONS.each_with_object({}) do |(key, cfg), memo|
+    timezone = cfg["timezone"]
+    starts_at = cfg["starts_at"]
+    ends_at = cfg["ends_at"]
+    memo[key.to_sym] = {
+      human_name: cfg["human_name"],
       calculate: -> {
-        timezone = "America/New_York"
         Time.use_zone(timezone) do
-          from = Time.parse("2025-03-14").beginning_of_day
-          to = Time.parse("2025-03-17").end_of_day
-          from.beginning_of_day..to.end_of_day
+          Time.zone.parse(starts_at).beginning_of_day..Time.zone.parse(ends_at).end_of_day
         end
       }
     }
-  }.freeze
+  end.freeze
+
+  RANGES = STANDARD_RANGES.merge(EVENT_RANGES).freeze
 
   class_methods do
     def time_range_filterable_field(field_name)

diff --git a/app/models/user.rb b/app/models/user.rb
@@ -9,6 +9,10 @@ class User < ApplicationRecord
 
   has_subscriptions
 
+  # Tracks which Hack Club events the user has coded during. EVENT_KEYS is
+  # sorted alphabetically so bit positions don't shift with events.json edits.
+  flag :event_participation, TimeRangeFilterable::EVENT_KEYS
+
   USERNAME_MAX_LENGTH = 21 # going over 21 overflows the navbar
 
   has_paper_trail

diff --git a/app/services/heartbeat_ingest.rb b/app/services/heartbeat_ingest.rb
@@ -120,7 +120,10 @@ def persist_direct_heartbeat(attrs)
       @user.heartbeats.find_by!(fields_hash: fields_hash)
     end
 
-    self.class.schedule_rollup_refresh(user: @user) if result.any? && @schedule_rollup_refresh
+    if result.any?
+      record_event_participation([ attrs[:time] ])
+      self.class.schedule_rollup_refresh(user: @user) if @schedule_rollup_refresh
+    end
     [ persisted, !result.any? ]
   end
 
@@ -194,9 +197,30 @@ def flush_import_batch(seen_hashes)
       record.merge(created_at: timestamp, updated_at: timestamp)
     end
 
-    ActiveRecord::Base.logger.silence do
+    inserted = ActiveRecord::Base.logger.silence do
       Heartbeat.insert_all(records, unique_by: [ :fields_hash ]).length
     end
+    record_event_participation(records.map { |r| r[:time] })
+    inserted
+  end
+
+  # OR each touched event's bit into the user's event_participation. The
+  # in-memory `unset?` check short-circuits before issuing any SQL once the
+  # bit is set, which is the common case after the first heartbeat per event.
+  def record_event_participation(times)
+    return if times.blank?
+
+    TimeRangeFilterable::EVENT_RANGES.each do |key, cfg|
+      next if @user.event_participation.set?(key)
+
+      range = cfg[:calculate].call
+      from_i = range.begin.to_i
+      to_i = range.end.to_i
+      next unless times.any? { |t| t >= from_i && t <= to_i }
+
+      User.where(id: @user.id).event_participations.set_all!(key)
-      User.where(id: @user.id).event_participations.set_all!(key)
+      User.where(id: @user.id).event_participation.set_all!(key)
-      User.where(id: @user.id).event_participations.set_all!(key)
+      User.where(id: @user.id).event_participation.set_all!(key)
+      @user.event_participation.set(key) # keep in-memory copy in sync for subsequent calls
+    end
   end
 
   def parse_user_agent(user_agent)

diff --git a/config/events.json b/config/events.json
@@ -0,0 +1,32 @@
+{
+  "flavortown": {
+    "human_name": "Flavortown",
+    "starts_at": "2025-12-15",
+    "ends_at": "2026-04-30",
+    "timezone": "America/New_York"
+  },
+  "summer_of_making": {
+    "human_name": "Summer of Making",
+    "starts_at": "2025-06-16",
+    "ends_at": "2025-09-30",
+    "timezone": "America/New_York"
+  },
+  "high_seas": {
+    "human_name": "High Seas",
+    "starts_at": "2024-10-30",
+    "ends_at": "2025-01-31",
+    "timezone": "America/New_York"
+  },
+  "low_skies": {
+    "human_name": "Low Skies",
+    "starts_at": "2024-10-03",
+    "ends_at": "2025-01-12",
+    "timezone": "America/New_York"
+  },
+  "scrapyard": {
+    "human_name": "Scrapyard Global",
+    "starts_at": "2025-03-14",
+    "ends_at": "2025-03-17",
+    "timezone": "America/New_York"
+  }
+}
diff --git a/db/migrate/20260521131313_add_event_participation_to_users.rb b/db/migrate/20260521131313_add_event_participation_to_users.rb
@@ -0,0 +1,5 @@
+class AddEventParticipationToUsers < ActiveRecord::Migration[8.1]
+  def change
+    add_column :users, :event_participation, :integer, default: 0, null: false
+  end
+end
diff --git a/db/migrate/20260521132654_add_event_participation_backfilled_to_users.rb b/db/migrate/20260521132654_add_event_participation_backfilled_to_users.rb
@@ -0,0 +1,12 @@
+class AddEventParticipationBackfilledToUsers < ActiveRecord::Migration[8.1]
+  def up
+    # Existing users start false (need backfill), future inserts default true
+    # (new users have no history to backfill)
+    add_column :users, :event_participation_backfilled, :boolean, default: false, null: false
+    change_column_default :users, :event_participation_backfilled, true
+  end
+
+  def down
+    remove_column :users, :event_participation_backfilled
+  end
+end