Add smart notification reminder system with frequency-aware scheduling

Replaces one-size-fits-all "2 days before" reminders with intelligent
scheduling based on task frequency. Infrequent tasks (annual) get 30-day
advance notice while frequent tasks (weekly) only get day-of reminders.

Key features:
- Frequency-aware pre-reminders: annual (30d, 14d, 7d), quarterly (7d, 3d),
  monthly (3d), bi-weekly (1d), daily/weekly/once (day-of only)
- Overdue tapering: daily for 3 days, then every 3 days, stops after 14 days
- Reminder log table prevents duplicate notifications per due date/stage
- Admin endpoint displays notification schedules for all frequencies
- Comprehensive test suite (100 random tasks, 61 days each, 10 test functions)

New files:
- internal/notifications/reminder_config.go - Editable schedule configuration
- internal/notifications/reminder_schedule.go - Schedule lookup logic
- internal/notifications/reminder_schedule_test.go - Dynamic test suite
- internal/models/reminder_log.go - TaskReminderLog model
- internal/repositories/reminder_repo.go - Reminder log repository
- migrations/010_add_task_reminder_log.{up,down}.sql

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

admin/src/app/(dashboard)/lookups/page.tsx

@@ -2,10 +2,10 @@
 
 import { useState } from 'react';
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
-import { Plus, Pencil, Trash2, GripVertical, X, Check } from 'lucide-react';
+import { Plus, Pencil, Trash2, GripVertical, X, Check, Bell, Info } from 'lucide-react';
 import { toast } from 'sonner';
 
-import { lookupsApi, type LookupItem, type CreateLookupRequest, type UpdateLookupRequest } from '@/lib/api';
+import { lookupsApi, type LookupItem, type CreateLookupRequest, type UpdateLookupRequest, type FrequencyItem, type OverduePolicy } from '@/lib/api';
 import { Button } from '@/components/ui/button';
 import { Input } from '@/components/ui/input';
 import { Tabs, TabsContent, TabsList, TabsTrigger } from '@/components/ui/tabs';
@@ -34,11 +34,18 @@ import {
   AlertDialogHeader,
   AlertDialogTitle,
 } from '@/components/ui/alert-dialog';
+import { Badge } from '@/components/ui/badge';
+import {
+  Tooltip,
+  TooltipContent,
+  TooltipProvider,
+  TooltipTrigger,
+} from '@/components/ui/tooltip';
 
 const lookupTabs = [
   { key: 'categories', label: 'Task Categories', api: lookupsApi.categories },
   { key: 'priorities', label: 'Task Priorities', api: lookupsApi.priorities },
-  { key: 'frequencies', label: 'Task Frequencies', api: lookupsApi.frequencies },
+  { key: 'frequencies', label: 'Task Frequencies', api: null }, // Handled separately
   { key: 'residenceTypes', label: 'Residence Types', api: lookupsApi.residenceTypes },
   { key: 'specialties', label: 'Contractor Specialties', api: lookupsApi.specialties },
 ];
@@ -305,6 +312,311 @@ function LookupTable({ lookupKey, api }: LookupTableProps) {
   );
 }
 
+// Specialized table for frequencies that shows notification schedules
+function FrequenciesTable() {
+  const queryClient = useQueryClient();
+  const [editingId, setEditingId] = useState<number | null>(null);
+  const [editingName, setEditingName] = useState('');
+  const [editingOrder, setEditingOrder] = useState(0);
+  const [isAdding, setIsAdding] = useState(false);
+  const [newName, setNewName] = useState('');
+  const [newOrder, setNewOrder] = useState(0);
+  const [deleteItem, setDeleteItem] = useState<FrequencyItem | null>(null);
+
+  const { data, isLoading } = useQuery({
+    queryKey: ['lookups', 'frequencies'],
+    queryFn: () => lookupsApi.frequencies.listWithPolicy(),
+  });
+
+  const items = data?.data ?? [];
+  const overduePolicy = data?.overdue_policy;
+
+  const createMutation = useMutation({
+    mutationFn: (data: CreateLookupRequest) => lookupsApi.frequencies.create(data),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ['lookups', 'frequencies'] });
+      setIsAdding(false);
+      setNewName('');
+      setNewOrder(0);
+      toast.success('Frequency created successfully');
+    },
+    onError: () => {
+      toast.error('Failed to create frequency');
+    },
+  });
+
+  const updateMutation = useMutation({
+    mutationFn: ({ id, data }: { id: number; data: UpdateLookupRequest }) => lookupsApi.frequencies.update(id, data),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ['lookups', 'frequencies'] });
+      setEditingId(null);
+      toast.success('Frequency updated successfully');
+    },
+    onError: () => {
+      toast.error('Failed to update frequency');
+    },
+  });
+
+  const deleteMutation = useMutation({
+    mutationFn: (id: number) => lookupsApi.frequencies.delete(id),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ['lookups', 'frequencies'] });
+      setDeleteItem(null);
+      toast.success('Frequency deleted successfully');
+    },
+    onError: () => {
+      toast.error('Failed to delete frequency');
+    },
+  });
+
+  const handleEdit = (item: FrequencyItem) => {
+    setEditingId(item.id);
+    setEditingName(item.name);
+    setEditingOrder(item.display_order);
+  };
+
+  const handleSave = () => {
+    if (!editingId) return;
+    updateMutation.mutate({
+      id: editingId,
+      data: {
+        name: editingName,
+        display_order: editingOrder,
+      },
+    });
+  };
+
+  const handleCreate = () => {
+    if (!newName.trim()) return;
+    createMutation.mutate({
+      name: newName,
+      display_order: newOrder,
+    });
+  };
+
+  const sortedItems = [...items].sort((a, b) => a.display_order - b.display_order);
+
+  if (isLoading) {
+    return <div className="flex items-center justify-center h-32 text-muted-foreground">Loading...</div>;
+  }
+
+  return (
+    <div className="space-y-4">
+      {/* Overdue Policy Info */}
+      {overduePolicy && (
+        <div className="p-4 bg-muted/50 rounded-lg border">
+          <div className="flex items-center gap-2 mb-2">
+            <Bell className="h-4 w-4 text-muted-foreground" />
+            <span className="font-medium text-sm">Overdue Reminder Policy</span>
+          </div>
+          <p className="text-sm text-muted-foreground">{overduePolicy.description}</p>
+          <div className="mt-2 flex flex-wrap gap-1">
+            {overduePolicy.overdue_days.map((day) => (
+              <Badge key={day} variant="secondary" className="text-xs">
+                Day {day}
+              </Badge>
+            ))}
+          </div>
+        </div>
+      )}
+
+      <div className="flex justify-end">
+        <Button onClick={() => setIsAdding(true)} disabled={isAdding}>
+          <Plus className="h-4 w-4 mr-2" />
+          Add Item
+        </Button>
+      </div>
+
+      <Table>
+        <TableHeader>
+          <TableRow>
+            <TableHead className="w-12">#</TableHead>
+            <TableHead>Name</TableHead>
+            <TableHead>Notification Schedule</TableHead>
+            <TableHead className="w-24">Order</TableHead>
+            <TableHead className="w-32">Actions</TableHead>
+          </TableRow>
+        </TableHeader>
+        <TableBody>
+          {isAdding && (
+            <TableRow>
+              <TableCell>
+                <GripVertical className="h-4 w-4 text-muted-foreground" />
+              </TableCell>
+              <TableCell>
+                <Input
+                  value={newName}
+                  onChange={(e) => setNewName(e.target.value)}
+                  placeholder="Enter name..."
+                  className="h-8"
+                  autoFocus
+                />
+              </TableCell>
+              <TableCell>
+                <span className="text-muted-foreground text-sm">Auto-assigned based on interval</span>
+              </TableCell>
+              <TableCell>
+                <Input
+                  type="number"
+                  value={newOrder}
+                  onChange={(e) => setNewOrder(parseInt(e.target.value) || 0)}
+                  className="h-8 w-16"
+                />
+              </TableCell>
+              <TableCell>
+                <div className="flex items-center gap-1">
+                  <Button
+                    variant="ghost"
+                    size="icon"
+                    className="h-8 w-8"
+                    onClick={handleCreate}
+                    disabled={createMutation.isPending || !newName.trim()}
+                  >
+                    <Check className="h-4 w-4 text-green-600" />
+                  </Button>
+                  <Button
+                    variant="ghost"
+                    size="icon"
+                    className="h-8 w-8"
+                    onClick={() => {
+                      setIsAdding(false);
+                      setNewName('');
+                      setNewOrder(0);
+                    }}
+                  >
+                    <X className="h-4 w-4 text-red-600" />
+                  </Button>
+                </div>
+              </TableCell>
+            </TableRow>
+          )}
+          {sortedItems.map((item) => (
+            <TableRow key={item.id}>
+              <TableCell>
+                <GripVertical className="h-4 w-4 text-muted-foreground" />
+              </TableCell>
+              <TableCell>
+                {editingId === item.id ? (
+                  <Input
+                    value={editingName}
+                    onChange={(e) => setEditingName(e.target.value)}
+                    className="h-8"
+                  />
+                ) : (
+                  <div>
+                    <div className="font-medium">{item.name}</div>
+                    {item.days !== null && (
+                      <div className="text-xs text-muted-foreground">
+                        {item.days} day{item.days !== 1 ? 's' : ''} interval
+                      </div>
+                    )}
+                  </div>
+                )}
+              </TableCell>
+              <TableCell>
+                <TooltipProvider>
+                  <Tooltip>
+                    <TooltipTrigger asChild>
+                      <div className="flex items-center gap-2">
+                        <Bell className="h-3 w-3 text-muted-foreground" />
+                        <span className="text-sm">{item.notification_schedule}</span>
+                      </div>
+                    </TooltipTrigger>
+                    <TooltipContent>
+                      <p className="text-xs">Reminder days before due: {item.reminder_days.join(', ') || 'Day-of only'}</p>
+                    </TooltipContent>
+                  </Tooltip>
+                </TooltipProvider>
+              </TableCell>
+              <TableCell>
+                {editingId === item.id ? (
+                  <Input
+                    type="number"
+                    value={editingOrder}
+                    onChange={(e) => setEditingOrder(parseInt(e.target.value) || 0)}
+                    className="h-8 w-16"
+                  />
+                ) : (
+                  item.display_order
+                )}
+              </TableCell>
+              <TableCell>
+                {editingId === item.id ? (
+                  <div className="flex items-center gap-1">
+                    <Button
+                      variant="ghost"
+                      size="icon"
+                      className="h-8 w-8"
+                      onClick={handleSave}
+                      disabled={updateMutation.isPending}
+                    >
+                      <Check className="h-4 w-4 text-green-600" />
+                    </Button>
+                    <Button
+                      variant="ghost"
+                      size="icon"
+                      className="h-8 w-8"
+                      onClick={() => setEditingId(null)}
+                    >
+                      <X className="h-4 w-4 text-red-600" />
+                    </Button>
+                  </div>
+                ) : (
+                  <div className="flex items-center gap-1">
+                    <Button
+                      variant="ghost"
+                      size="icon"
+                      className="h-8 w-8"
+                      onClick={() => handleEdit(item)}
+                    >
+                      <Pencil className="h-4 w-4" />
+                    </Button>
+                    <Button
+                      variant="ghost"
+                      size="icon"
+                      className="h-8 w-8"
+                      onClick={() => setDeleteItem(item)}
+                    >
+                      <Trash2 className="h-4 w-4 text-red-600" />
+                    </Button>
+                  </div>
+                )}
+              </TableCell>
+            </TableRow>
+          ))}
+          {sortedItems.length === 0 && !isAdding && (
+            <TableRow>
+              <TableCell colSpan={5} className="text-center text-muted-foreground py-8">
+                No frequencies found. Click &quot;Add Item&quot; to create one.
+              </TableCell>
+            </TableRow>
+          )}
+        </TableBody>
+      </Table>
+
+      <AlertDialog open={!!deleteItem} onOpenChange={(open) => !open && setDeleteItem(null)}>
+        <AlertDialogContent>
+          <AlertDialogHeader>
+            <AlertDialogTitle>Delete Frequency</AlertDialogTitle>
+            <AlertDialogDescription>
+              Are you sure you want to delete &quot;{deleteItem?.name}&quot;? This action cannot be undone.
+            </AlertDialogDescription>
+          </AlertDialogHeader>
+          <AlertDialogFooter>
+            <AlertDialogCancel>Cancel</AlertDialogCancel>
+            <AlertDialogAction
+              onClick={() => deleteItem && deleteMutation.mutate(deleteItem.id)}
+              className="bg-red-600 hover:bg-red-700"
+            >
+              {deleteMutation.isPending ? 'Deleting...' : 'Delete'}
+            </AlertDialogAction>
+          </AlertDialogFooter>
+        </AlertDialogContent>
+      </AlertDialog>
+    </div>
+  );
+}
+
 export default function LookupsPage() {
   return (
     <div className="space-y-6">
@@ -333,7 +645,11 @@ export default function LookupsPage() {
             </TabsList>
             {lookupTabs.map((tab) => (
               <TabsContent key={tab.key} value={tab.key} className="mt-4">
-                <LookupTable lookupKey={tab.key} api={tab.api} />
+                {tab.key === 'frequencies' ? (
+                  <FrequenciesTable />
+                ) : (
+                  <LookupTable lookupKey={tab.key} api={tab.api!} />
+                )}
               </TabsContent>
             ))}
           </Tabs>

admin/src/lib/api.ts

@@ -473,6 +473,29 @@ export interface LookupItem {
   color?: string;
 }
 
+// Frequency Item with notification schedule
+export interface FrequencyItem extends LookupItem {
+  days: number | null;
+  notification_schedule: string;
+  reminder_days: number[];
+}
+
+// Overdue Policy
+export interface OverduePolicy {
+  daily_reminder_days: number;
+  taper_interval_days: number;
+  max_overdue_days: number;
+  description: string;
+  overdue_days: number[];
+}
+
+// Frequencies List Response
+export interface FrequenciesListResponse {
+  data: FrequencyItem[];
+  total: number;
+  overdue_policy: OverduePolicy;
+}
+
 export interface CreateLookupRequest {
   name: string;
   display_order?: number;
@@ -517,7 +540,27 @@ const createLookupApi = (endpoint: string) => ({
 export const lookupsApi = {
   categories: createLookupApi('categories'),
   priorities: createLookupApi('priorities'),
-  frequencies: createLookupApi('frequencies'),
+  frequencies: {
+    list: async (): Promise<FrequencyItem[]> => {
+      const response = await api.get<FrequenciesListResponse>('/lookups/frequencies');
+      return response.data.data;
+    },
+    listWithPolicy: async (): Promise<FrequenciesListResponse> => {
+      const response = await api.get<FrequenciesListResponse>('/lookups/frequencies');
+      return response.data;
+    },
+    create: async (data: CreateLookupRequest): Promise<FrequencyItem> => {
+      const response = await api.post<FrequencyItem>('/lookups/frequencies', data);
+      return response.data;
+    },
+    update: async (id: number, data: UpdateLookupRequest): Promise<FrequencyItem> => {
+      const response = await api.put<FrequencyItem>(`/lookups/frequencies/${id}`, data);
+      return response.data;
+    },
+    delete: async (id: number): Promise<void> => {
+      await api.delete(`/lookups/frequencies/${id}`);
+    },
+  },
   residenceTypes: createLookupApi('residence-types'),
   specialties: createLookupApi('specialties'),
 };

internal/admin/handlers/lookup_handler.go

@@ -11,6 +11,7 @@ import (
 
 	"github.com/treytartt/casera-api/internal/admin/dto"
 	"github.com/treytartt/casera-api/internal/models"
+	"github.com/treytartt/casera-api/internal/notifications"
 	"github.com/treytartt/casera-api/internal/services"
 )
 
@@ -412,10 +413,12 @@ func (h *AdminLookupHandler) DeletePriority(c echo.Context) error {
 // ========== Task Frequencies ==========
 
 type TaskFrequencyResponse struct {
-	ID           uint  `json:"id"`
+	ID                   uint   `json:"id"`
-	Name         string `json:"name"`
+	Name                 string `json:"name"`
-	Days         *int   `json:"days"`
+	Days                 *int   `json:"days"`
-	DisplayOrder int    `json:"display_order"`
+	DisplayOrder         int    `json:"display_order"`
+	NotificationSchedule string `json:"notification_schedule"`
+	ReminderDays         []int  `json:"reminder_days"`
 }
 
 type CreateUpdateFrequencyRequest struct {
@@ -432,15 +435,34 @@ func (h *AdminLookupHandler) ListFrequencies(c echo.Context) error {
 
 	responses := make([]TaskFrequencyResponse, len(frequencies))
 	for i, f := range frequencies {
+		// Get notification schedule for this frequency
+		schedule := notifications.GetScheduleForFrequency(f.Days)
+		humanReadable := notifications.GetHumanReadableSchedule(f.Days)
+
 		responses[i] = TaskFrequencyResponse{
-			ID:           f.ID,
+			ID:                   f.ID,
-			Name:         f.Name,
+			Name:                 f.Name,
-			Days:         f.Days,
+			Days:                 f.Days,
-			DisplayOrder: f.DisplayOrder,
+			DisplayOrder:         f.DisplayOrder,
+			NotificationSchedule: humanReadable,
+			ReminderDays:         schedule,
 		}
 	}
 
-	return c.JSON(http.StatusOK, map[string]interface{}{"data": responses, "total": len(responses)})
+	// Include overdue policy in response
+	overduePolicy := map[string]interface{}{
+		"daily_reminder_days": notifications.OverdueConfig.DailyReminderDays,
+		"taper_interval_days": notifications.OverdueConfig.TaperIntervalDays,
+		"max_overdue_days":    notifications.OverdueConfig.MaxOverdueDays,
+		"description":         "Daily for first " + strconv.Itoa(notifications.OverdueConfig.DailyReminderDays) + " days, then every " + strconv.Itoa(notifications.OverdueConfig.TaperIntervalDays) + " days, stops after " + strconv.Itoa(notifications.OverdueConfig.MaxOverdueDays) + " days",
+		"overdue_days":        notifications.GetOverdueReminderDays(),
+	}
+
+	return c.JSON(http.StatusOK, map[string]interface{}{
+		"data":           responses,
+		"total":          len(responses),
+		"overdue_policy": overduePolicy,
+	})
 }
 
 func (h *AdminLookupHandler) CreateFrequency(c echo.Context) error {
@@ -464,11 +486,17 @@ func (h *AdminLookupHandler) CreateFrequency(c echo.Context) error {
 	// Refresh cache after creating
 	h.refreshFrequenciesCache(c.Request().Context())
 
+	// Get notification schedule for this frequency
+	schedule := notifications.GetScheduleForFrequency(frequency.Days)
+	humanReadable := notifications.GetHumanReadableSchedule(frequency.Days)
+
 	return c.JSON(http.StatusCreated, TaskFrequencyResponse{
-		ID:           frequency.ID,
+		ID:                   frequency.ID,
-		Name:         frequency.Name,
+		Name:                 frequency.Name,
-		Days:         frequency.Days,
+		Days:                 frequency.Days,
-		DisplayOrder: frequency.DisplayOrder,
+		DisplayOrder:         frequency.DisplayOrder,
+		NotificationSchedule: humanReadable,
+		ReminderDays:         schedule,
 	})
 }
 
@@ -504,11 +532,17 @@ func (h *AdminLookupHandler) UpdateFrequency(c echo.Context) error {
 	// Refresh cache after updating
 	h.refreshFrequenciesCache(c.Request().Context())
 
+	// Get notification schedule for this frequency
+	schedule := notifications.GetScheduleForFrequency(frequency.Days)
+	humanReadable := notifications.GetHumanReadableSchedule(frequency.Days)
+
 	return c.JSON(http.StatusOK, TaskFrequencyResponse{
-		ID:           frequency.ID,
+		ID:                   frequency.ID,
-		Name:         frequency.Name,
+		Name:                 frequency.Name,
-		Days:         frequency.Days,
+		Days:                 frequency.Days,
-		DisplayOrder: frequency.DisplayOrder,
+		DisplayOrder:         frequency.DisplayOrder,
+		NotificationSchedule: humanReadable,
+		ReminderDays:         schedule,
 	})
 }
 
@@ -770,5 +804,73 @@ func (h *AdminLookupHandler) DeleteSpecialty(c echo.Context) error {
 	return c.JSON(http.StatusOK, map[string]interface{}{"message": "Specialty deleted successfully"})
 }
 
+// ========== Notification Schedules ==========
+
+// FrequencyScheduleResponse represents a frequency with its notification schedule
+type FrequencyScheduleResponse struct {
+	ID                   uint   `json:"id"`
+	Name                 string `json:"name"`
+	Days                 *int   `json:"days"`
+	NotificationSchedule string `json:"notification_schedule"`
+	ReminderDays         []int  `json:"reminder_days"`
+}
+
+// OverduePolicyResponse represents the overdue reminder policy
+type OverduePolicyResponse struct {
+	DailyReminderDays int    `json:"daily_reminder_days"`
+	TaperIntervalDays int    `json:"taper_interval_days"`
+	MaxOverdueDays    int    `json:"max_overdue_days"`
+	Description       string `json:"description"`
+	OverdueDays       []int  `json:"overdue_days"`
+}
+
+// NotificationSchedulesResponse is the full response for notification schedules
+type NotificationSchedulesResponse struct {
+	Frequencies   []FrequencyScheduleResponse `json:"frequencies"`
+	OverduePolicy OverduePolicyResponse       `json:"overdue_policy"`
+}
+
+// GetNotificationSchedules handles GET /api/admin/lookups/notification-schedules
+// Returns the notification schedule configuration for all frequencies
+func (h *AdminLookupHandler) GetNotificationSchedules(c echo.Context) error {
+	// Get all frequencies from database
+	var frequencies []models.TaskFrequency
+	if err := h.db.Order("display_order ASC, name ASC").Find(&frequencies).Error; err != nil {
+		return c.JSON(http.StatusInternalServerError, map[string]interface{}{"error": "Failed to fetch frequencies"})
+	}
+
+	// Build frequency schedules with notification info
+	frequencyResponses := make([]FrequencyScheduleResponse, len(frequencies))
+	for i, f := range frequencies {
+		// Get the notification schedule for this frequency's days
+		schedule := notifications.GetScheduleForFrequency(f.Days)
+		humanReadable := notifications.GetHumanReadableSchedule(f.Days)
+
+		frequencyResponses[i] = FrequencyScheduleResponse{
+			ID:                   f.ID,
+			Name:                 f.Name,
+			Days:                 f.Days,
+			NotificationSchedule: humanReadable,
+			ReminderDays:         schedule,
+		}
+	}
+
+	// Build overdue policy response
+	overduePolicy := OverduePolicyResponse{
+		DailyReminderDays: notifications.OverdueConfig.DailyReminderDays,
+		TaperIntervalDays: notifications.OverdueConfig.TaperIntervalDays,
+		MaxOverdueDays:    notifications.OverdueConfig.MaxOverdueDays,
+		Description:       "Daily for first " + strconv.Itoa(notifications.OverdueConfig.DailyReminderDays) + " days, then every " + strconv.Itoa(notifications.OverdueConfig.TaperIntervalDays) + " days, stops after " + strconv.Itoa(notifications.OverdueConfig.MaxOverdueDays) + " days",
+		OverdueDays:       notifications.GetOverdueReminderDays(),
+	}
+
+	response := NotificationSchedulesResponse{
+		Frequencies:   frequencyResponses,
+		OverduePolicy: overduePolicy,
+	}
+
+	return c.JSON(http.StatusOK, response)
+}
+
 // Ensure dto import is used
 var _ = dto.PaginationParams{}

internal/admin/routes.go

@@ -274,6 +274,9 @@ func SetupRoutes(router *echo.Echo, db *gorm.DB, cfg *config.Config, deps *Depen
 				frequencies.DELETE("/:id", lookupHandler.DeleteFrequency)
 			}
 
+			// Notification Schedules (read-only, shows schedule for each frequency)
+			protected.GET("/lookups/notification-schedules", lookupHandler.GetNotificationSchedules)
+
 			// Residence Types
 			residenceTypes := protected.Group("/lookups/residence-types")
 			{

internal/models/reminder_log.go

@@ -0,0 +1,91 @@
+package models
+
+import (
+	"fmt"
+	"time"
+)
+
+// ReminderStage represents the stage of a task reminder
+type ReminderStage string
+
+const (
+	// Pre-due date reminders (days before)
+	ReminderStage30Days ReminderStage = "reminder_30d"
+	ReminderStage14Days ReminderStage = "reminder_14d"
+	ReminderStage7Days  ReminderStage = "reminder_7d"
+	ReminderStage3Days  ReminderStage = "reminder_3d"
+	ReminderStage1Day   ReminderStage = "reminder_1d"
+	ReminderStageDayOf  ReminderStage = "day_of"
+
+	// Overdue reminders (days after)
+	ReminderStageOverdue1  ReminderStage = "overdue_1"
+	ReminderStageOverdue2  ReminderStage = "overdue_2"
+	ReminderStageOverdue3  ReminderStage = "overdue_3"
+	ReminderStageOverdue4  ReminderStage = "overdue_4"
+	ReminderStageOverdue7  ReminderStage = "overdue_7"
+	ReminderStageOverdue10 ReminderStage = "overdue_10"
+	ReminderStageOverdue13 ReminderStage = "overdue_13"
+)
+
+// GetReminderStageForDaysBefore returns the reminder stage for days before due date
+func GetReminderStageForDaysBefore(days int) ReminderStage {
+	switch days {
+	case 30:
+		return ReminderStage30Days
+	case 14:
+		return ReminderStage14Days
+	case 7:
+		return ReminderStage7Days
+	case 3:
+		return ReminderStage3Days
+	case 1:
+		return ReminderStage1Day
+	case 0:
+		return ReminderStageDayOf
+	default:
+		// For any other number of days, create a custom stage
+		return ReminderStage(fmt.Sprintf("reminder_%dd", days))
+	}
+}
+
+// GetReminderStageForDaysOverdue returns the reminder stage for days overdue
+func GetReminderStageForDaysOverdue(days int) ReminderStage {
+	switch days {
+	case 1:
+		return ReminderStageOverdue1
+	case 2:
+		return ReminderStageOverdue2
+	case 3:
+		return ReminderStageOverdue3
+	case 4:
+		return ReminderStageOverdue4
+	case 7:
+		return ReminderStageOverdue7
+	case 10:
+		return ReminderStageOverdue10
+	case 13:
+		return ReminderStageOverdue13
+	default:
+		// For any other overdue day, format as overdue_N
+		return ReminderStage(fmt.Sprintf("overdue_%d", days))
+	}
+}
+
+// TaskReminderLog tracks which reminders have been sent to prevent duplicates
+type TaskReminderLog struct {
+	ID             uint          `gorm:"primaryKey" json:"id"`
+	TaskID         uint          `gorm:"column:task_id;not null;index:idx_reminderlog_task_user_date" json:"task_id"`
+	Task           *Task         `gorm:"foreignKey:TaskID" json:"-"`
+	UserID         uint          `gorm:"column:user_id;not null;index:idx_reminderlog_task_user_date" json:"user_id"`
+	User           *User         `gorm:"foreignKey:UserID" json:"-"`
+	DueDate        time.Time     `gorm:"column:due_date;type:date;not null;index:idx_reminderlog_task_user_date" json:"due_date"`
+	ReminderStage  ReminderStage `gorm:"column:reminder_stage;size:20;not null" json:"reminder_stage"`
+	SentAt         time.Time     `gorm:"column:sent_at;default:CURRENT_TIMESTAMP;index:idx_reminderlog_sent_at" json:"sent_at"`
+	NotificationID *uint         `gorm:"column:notification_id" json:"notification_id"`
+	Notification   *Notification `gorm:"foreignKey:NotificationID" json:"-"`
+}
+
+// TableName returns the table name for GORM
+func (TaskReminderLog) TableName() string {
+	return "task_reminderlog"
+}

internal/notifications/reminder_config.go

@@ -0,0 +1,63 @@
+package notifications
+
+// ============================================================
+// REMINDER CONFIGURATION
+// Edit these values to adjust notification behavior
+// ============================================================
+
+// OverdueConfig controls when and how often overdue reminders are sent
+var OverdueConfig = struct {
+	DailyReminderDays int // Send daily reminders for first N days overdue
+	TaperIntervalDays int // After daily period, remind every N days
+	MaxOverdueDays    int // Stop reminding after N days overdue
+}{
+	DailyReminderDays: 3,  // Daily for days 1-3
+	TaperIntervalDays: 3,  // Then every 3 days (4, 7, 10, 13)
+	MaxOverdueDays:    14, // Stop after 14 days
+}
+
+// FrequencySchedules - EXPLICIT entry for each of the 9 seeded frequencies
+// Key: interval days (matches TaskFrequency.days in DB, 0 = Once/null)
+// Value: array of days before due date to send reminders (0 = day-of)
+//
+// To add a reminder: append the number of days before to the slice
+// Example: FrequencySchedules[30] = []int{7, 3, 0} adds 7-day warning to Monthly
+var FrequencySchedules = map[int][]int{
+	0:   {0},             // 1. Once (null/0): day-of only
+	1:   {0},             // 2. Daily: day-of only
+	7:   {0},             // 3. Weekly: day-of only
+	14:  {1, 0},          // 4. Bi-Weekly: 1 day before, day-of
+	30:  {3, 0},          // 5. Monthly: 3 days before, day-of
+	90:  {7, 3, 0},       // 6. Quarterly: 7d, 3d, day-of
+	180: {14, 7, 0},      // 7. Semi-Annually: 14d, 7d, day-of
+	365: {30, 14, 7, 0},  // 8. Annually: 30d, 14d, 7d, day-of
+}
+
+// HumanReadableSchedule returns admin-friendly description for each frequency
+// Key: interval days (matches FrequencySchedules keys)
+// Value: human-readable description of the reminder schedule
+var HumanReadableSchedule = map[int]string{
+	0:   "Day-of → Overdue (tapering)",
+	1:   "Day-of → Overdue (tapering)",
+	7:   "Day-of → Overdue (tapering)",
+	14:  "1 day before → Day-of → Overdue",
+	30:  "3 days before → Day-of → Overdue",
+	90:  "7d → 3d → Day-of → Overdue",
+	180: "14d → 7d → Day-of → Overdue",
+	365: "30d → 14d → 7d → Day-of → Overdue",
+}
+
+// FrequencyNames maps interval days to frequency names for display
+var FrequencyNames = map[int]string{
+	0:   "Once",
+	1:   "Daily",
+	7:   "Weekly",
+	14:  "Bi-Weekly",
+	30:  "Monthly",
+	90:  "Quarterly",
+	180: "Semi-Annually",
+	365: "Annually",
+}
+
+// OrderedFrequencies defines the display order for frequencies
+var OrderedFrequencies = []int{0, 1, 7, 14, 30, 90, 180, 365}

internal/notifications/reminder_schedule.go

@@ -0,0 +1,198 @@
+package notifications
+
+import (
+	"slices"
+	"time"
+)
+
+// GetScheduleForFrequency returns the reminder schedule (days before due date)
+// based on the task's frequency interval days.
+// Returns nil or 0 interval as Once schedule.
+func GetScheduleForFrequency(intervalDays *int) []int {
+	if intervalDays == nil || *intervalDays == 0 {
+		return FrequencySchedules[0] // Once schedule
+	}
+
+	days := *intervalDays
+
+	// Check for exact match first
+	if schedule, exists := FrequencySchedules[days]; exists {
+		return schedule
+	}
+
+	// For Custom frequencies, find the nearest tier
+	return GetScheduleForCustomInterval(days)
+}
+
+// GetScheduleForCustomInterval looks up schedule for Custom frequency
+// based on CustomIntervalDays value - finds nearest tier
+func GetScheduleForCustomInterval(days int) []int {
+	// Ordered tiers from smallest to largest
+	tiers := []int{1, 7, 14, 30, 90, 180, 365}
+
+	for _, tier := range tiers {
+		if days <= tier {
+			return FrequencySchedules[tier]
+		}
+	}
+
+	// Fallback to annual schedule for intervals > 365 days
+	return FrequencySchedules[365]
+}
+
+// ShouldSendOverdueReminder checks if we should send an overdue reminder
+// for a task that is daysOverdue days past its due date.
+//
+// Returns true if:
+// - Days 1 to DailyReminderDays: every day
+// - Days DailyReminderDays+1 to MaxOverdueDays: every TaperIntervalDays
+// - After MaxOverdueDays: never
+func ShouldSendOverdueReminder(daysOverdue int) bool {
+	if daysOverdue <= 0 {
+		return false
+	}
+
+	// Phase 1: Daily reminders for first N days
+	if daysOverdue <= OverdueConfig.DailyReminderDays {
+		return true
+	}
+
+	// Phase 2: Tapered reminders (every N days)
+	if daysOverdue <= OverdueConfig.MaxOverdueDays {
+		// Calculate which day in the taper phase
+		daysSinceDaily := daysOverdue - OverdueConfig.DailyReminderDays
+		// Send on days that are multiples of TaperIntervalDays after daily phase
+		// e.g., with DailyReminderDays=3, TaperIntervalDays=3:
+		// Day 4 (daysSinceDaily=1): 1 % 3 = 1 (no)
+		// Day 5 (daysSinceDaily=2): 2 % 3 = 2 (no)
+		// Day 6 (daysSinceDaily=3): 3 % 3 = 0 (yes) -> but we want day 4, 7, 10, 13
+		// Correcting: we want to send on daysSinceDaily = 1, 4, 7, 10...
+		// So (daysSinceDaily - 1) % TaperIntervalDays == 0
+		return (daysSinceDaily-1)%OverdueConfig.TaperIntervalDays == 0
+	}
+
+	// Phase 3: No more reminders
+	return false
+}
+
+// GetOverdueReminderDays returns all the days on which overdue reminders
+// should be sent, based on the current OverdueConfig.
+func GetOverdueReminderDays() []int {
+	var days []int
+
+	// Add daily reminder days
+	for i := 1; i <= OverdueConfig.DailyReminderDays; i++ {
+		days = append(days, i)
+	}
+
+	// Add tapered reminder days
+	for i := OverdueConfig.DailyReminderDays + 1; i <= OverdueConfig.MaxOverdueDays; i++ {
+		if ShouldSendOverdueReminder(i) {
+			days = append(days, i)
+		}
+	}
+
+	return days
+}
+
+// GetReminderStageForToday determines which reminder stage applies today
+// for a task with the given due date and frequency.
+//
+// Returns:
+// - "reminder_Nd" if task is N days away and in schedule
+// - "day_of" if task is due today
+// - "overdue_N" if task is N days overdue and should be reminded
+// - empty string if no reminder should be sent today
+func GetReminderStageForToday(dueDate time.Time, frequencyDays *int, today time.Time) string {
+	// Normalize to date only (midnight)
+	dueDate = time.Date(dueDate.Year(), dueDate.Month(), dueDate.Day(), 0, 0, 0, 0, time.UTC)
+	today = time.Date(today.Year(), today.Month(), today.Day(), 0, 0, 0, 0, time.UTC)
+
+	// Calculate days difference
+	diff := int(dueDate.Sub(today).Hours() / 24)
+
+	if diff > 0 {
+		// Task is in the future - check pre-due reminders
+		schedule := GetScheduleForFrequency(frequencyDays)
+		if slices.Contains(schedule, diff) {
+			return formatDaysBeforeStage(diff)
+		}
+		return ""
+	} else if diff == 0 {
+		// Task is due today
+		return "day_of"
+	} else {
+		// Task is overdue
+		daysOverdue := -diff
+		if ShouldSendOverdueReminder(daysOverdue) {
+			return formatOverdueStage(daysOverdue)
+		}
+		return ""
+	}
+}
+
+// formatDaysBeforeStage returns the stage string for days before due date
+func formatDaysBeforeStage(days int) string {
+	if days == 0 {
+		return "day_of"
+	}
+	return "reminder_" + itoa(days) + "d"
+}
+
+// formatOverdueStage returns the stage string for days overdue
+func formatOverdueStage(days int) string {
+	return "overdue_" + itoa(days)
+}
+
+// itoa is a simple int to string helper
+func itoa(i int) string {
+	if i == 0 {
+		return "0"
+	}
+	if i < 0 {
+		return "-" + itoa(-i)
+	}
+	s := ""
+	for i > 0 {
+		s = string(rune('0'+i%10)) + s
+		i /= 10
+	}
+	return s
+}
+
+// GetHumanReadableSchedule returns a human-readable description of the
+// notification schedule for a given frequency interval.
+func GetHumanReadableSchedule(intervalDays *int) string {
+	days := 0
+	if intervalDays != nil {
+		days = *intervalDays
+	}
+
+	if desc, exists := HumanReadableSchedule[days]; exists {
+		return desc
+	}
+
+	// For custom intervals, find the nearest tier
+	tiers := []int{1, 7, 14, 30, 90, 180, 365}
+	for _, tier := range tiers {
+		if days <= tier {
+			return HumanReadableSchedule[tier] + " (custom)"
+		}
+	}
+
+	return HumanReadableSchedule[365] + " (custom)"
+}
+
+// GetFrequencyName returns the human-readable name for a frequency interval
+func GetFrequencyName(intervalDays *int) string {
+	days := 0
+	if intervalDays != nil {
+		days = *intervalDays
+	}
+
+	if name, exists := FrequencyNames[days]; exists {
+		return name
+	}
+
+	return "Custom"
+}

internal/notifications/reminder_schedule_test.go

@@ -0,0 +1,524 @@
+package notifications
+
+import (
+	"fmt"
+	"math/rand"
+	"slices"
+	"testing"
+	"time"
+)
+
+// TestReminderScheduleWith100RandomTasks creates 100 tasks with random frequencies
+// and validates that notifications are sent on exactly the right days according to
+// the current FrequencySchedules and OverdueConfig.
+//
+// This test is dynamic - it reads from the config, so if the config changes,
+// the test will still validate the correct behavior.
+func TestReminderScheduleWith100RandomTasks(t *testing.T) {
+	// Seed random for reproducibility in tests (use current time for variety)
+	rng := rand.New(rand.NewSource(time.Now().UnixNano()))
+
+	// Available frequency intervals (from OrderedFrequencies)
+	// We'll also add some custom intervals to test the tier mapping
+	frequencyIntervals := []int{0, 1, 7, 14, 30, 90, 180, 365}
+	customIntervals := []int{5, 10, 20, 45, 120, 200, 400} // Custom intervals to test tier mapping
+
+	allIntervals := append(frequencyIntervals, customIntervals...)
+
+	// Base date for tests - use a fixed date for deterministic behavior
+	baseDate := time.Date(2025, 6, 15, 0, 0, 0, 0, time.UTC)
+
+	// Track test statistics
+	tasksCreated := 0
+	daysSimulated := 0
+	notificationsSent := 0
+	notificationsExpected := 0
+
+	for i := 0; i < 100; i++ {
+		// Random frequency
+		intervalIdx := rng.Intn(len(allIntervals))
+		intervalDays := allIntervals[intervalIdx]
+
+		// Random due date offset (-30 to +30 days from base date)
+		dueDateOffset := rng.Intn(61) - 30
+		dueDate := baseDate.AddDate(0, 0, dueDateOffset)
+
+		// Create frequency pointer (nil for "Once" which is interval 0)
+		var frequencyDays *int
+		if intervalDays > 0 {
+			frequencyDays = &intervalDays
+		}
+
+		tasksCreated++
+
+		// Get the expected schedule for this frequency
+		expectedSchedule := GetScheduleForFrequency(frequencyDays)
+		expectedOverdueDays := GetOverdueReminderDays()
+
+		// Simulate each day from 45 days before to 15 days after due date
+		for dayOffset := -45; dayOffset <= 15; dayOffset++ {
+			today := dueDate.AddDate(0, 0, -dayOffset) // dayOffset is days until due, so we subtract
+			daysSimulated++
+
+			// Get the reminder stage for today
+			stage := GetReminderStageForToday(dueDate, frequencyDays, today)
+
+			// Calculate what we expect
+			expectedStage := calculateExpectedStage(dayOffset, expectedSchedule, expectedOverdueDays)
+
+			if stage != expectedStage {
+				t.Errorf("Task %d (interval=%d, dueDate=%s): on %s (dayOffset=%d), got stage=%q, expected=%q",
+					i+1, intervalDays, dueDate.Format("2006-01-02"),
+					today.Format("2006-01-02"), dayOffset, stage, expectedStage)
+			}
+
+			if stage != "" {
+				notificationsSent++
+			}
+			if expectedStage != "" {
+				notificationsExpected++
+			}
+		}
+	}
+
+	t.Logf("Test Summary:")
+	t.Logf("  Tasks created: %d", tasksCreated)
+	t.Logf("  Days simulated: %d", daysSimulated)
+	t.Logf("  Notifications sent: %d", notificationsSent)
+	t.Logf("  Notifications expected: %d", notificationsExpected)
+
+	if notificationsSent != notificationsExpected {
+		t.Errorf("Notification count mismatch: sent=%d, expected=%d", notificationsSent, notificationsExpected)
+	}
+}
+
+// calculateExpectedStage determines what stage should be returned based on the config
+func calculateExpectedStage(dayOffset int, preReminderDays []int, overdueDays []int) string {
+	if dayOffset > 0 {
+		// Task is in the future (dayOffset days until due)
+		if slices.Contains(preReminderDays, dayOffset) {
+			return formatDaysBeforeStage(dayOffset)
+		}
+		return ""
+	} else if dayOffset == 0 {
+		// Task is due today
+		return "day_of"
+	} else {
+		// Task is overdue (-dayOffset days overdue)
+		daysOverdue := -dayOffset
+		if slices.Contains(overdueDays, daysOverdue) {
+			return formatOverdueStage(daysOverdue)
+		}
+		return ""
+	}
+}
+
+// TestEachFrequencySchedule validates each frequency's schedule explicitly
+func TestEachFrequencySchedule(t *testing.T) {
+	dueDate := time.Date(2025, 6, 15, 0, 0, 0, 0, time.UTC)
+
+	// Test each configured frequency
+	for intervalDays, expectedSchedule := range FrequencySchedules {
+		t.Run(fmt.Sprintf("Interval_%d_days", intervalDays), func(t *testing.T) {
+			var frequencyDays *int
+			if intervalDays > 0 {
+				frequencyDays = &intervalDays
+			}
+
+			// Verify all expected reminder days trigger notifications
+			for _, reminderDay := range expectedSchedule {
+				today := dueDate.AddDate(0, 0, -reminderDay)
+				stage := GetReminderStageForToday(dueDate, frequencyDays, today)
+
+				expectedStage := formatDaysBeforeStage(reminderDay)
+				if stage != expectedStage {
+					t.Errorf("Reminder %d days before: got %q, expected %q", reminderDay, stage, expectedStage)
+				}
+			}
+
+			// Verify days NOT in the schedule don't trigger notifications (before due date)
+			for day := 1; day <= 45; day++ {
+				if !slices.Contains(expectedSchedule, day) {
+					today := dueDate.AddDate(0, 0, -day)
+					stage := GetReminderStageForToday(dueDate, frequencyDays, today)
+
+					if stage != "" {
+						t.Errorf("Day %d before due should NOT send notification for interval %d, but got %q",
+							day, intervalDays, stage)
+					}
+				}
+			}
+		})
+	}
+}
+
+// TestOverdueReminderSchedule validates the overdue tapering logic
+func TestOverdueReminderSchedule(t *testing.T) {
+	dueDate := time.Date(2025, 6, 15, 0, 0, 0, 0, time.UTC)
+
+	// Use nil frequency (Once) - overdue logic is the same for all frequencies
+	var frequencyDays *int
+
+	// Get expected overdue days from config
+	expectedOverdueDays := GetOverdueReminderDays()
+
+	t.Logf("OverdueConfig: DailyReminderDays=%d, TaperIntervalDays=%d, MaxOverdueDays=%d",
+		OverdueConfig.DailyReminderDays, OverdueConfig.TaperIntervalDays, OverdueConfig.MaxOverdueDays)
+	t.Logf("Expected overdue reminder days: %v", expectedOverdueDays)
+
+	// Test each day from 1 to MaxOverdueDays + 5
+	for daysOverdue := 1; daysOverdue <= OverdueConfig.MaxOverdueDays+5; daysOverdue++ {
+		today := dueDate.AddDate(0, 0, daysOverdue)
+		stage := GetReminderStageForToday(dueDate, frequencyDays, today)
+
+		shouldSend := slices.Contains(expectedOverdueDays, daysOverdue)
+		expectedStage := ""
+		if shouldSend {
+			expectedStage = formatOverdueStage(daysOverdue)
+		}
+
+		if stage != expectedStage {
+			t.Errorf("Day %d overdue: got %q, expected %q (shouldSend=%v)",
+				daysOverdue, stage, expectedStage, shouldSend)
+		}
+	}
+}
+
+// TestCustomIntervalTierMapping validates that custom intervals map to correct tiers
+func TestCustomIntervalTierMapping(t *testing.T) {
+	testCases := []struct {
+		customInterval  int
+		expectedTier    int
+		expectedMessage string
+	}{
+		{2, 7, "2 days should map to Weekly (7) tier"},
+		{5, 7, "5 days should map to Weekly (7) tier"},
+		{8, 14, "8 days should map to Bi-Weekly (14) tier"},
+		{10, 14, "10 days should map to Bi-Weekly (14) tier"},
+		{20, 30, "20 days should map to Monthly (30) tier"},
+		{45, 90, "45 days should map to Quarterly (90) tier"},
+		{100, 180, "100 days should map to Semi-Annually (180) tier"},
+		{200, 365, "200 days should map to Annually (365) tier"},
+		{500, 365, "500 days should map to Annually (365) tier - fallback"},
+	}
+
+	for _, tc := range testCases {
+		t.Run(fmt.Sprintf("CustomInterval_%d", tc.customInterval), func(t *testing.T) {
+			schedule := GetScheduleForCustomInterval(tc.customInterval)
+			expectedSchedule := FrequencySchedules[tc.expectedTier]
+
+			if !slices.Equal(schedule, expectedSchedule) {
+				t.Errorf("%s: got schedule %v, expected %v (tier %d)",
+					tc.expectedMessage, schedule, expectedSchedule, tc.expectedTier)
+			}
+		})
+	}
+}
+
+// TestDayOfNotification ensures day-of notifications always fire
+func TestDayOfNotification(t *testing.T) {
+	dueDate := time.Date(2025, 6, 15, 0, 0, 0, 0, time.UTC)
+	today := dueDate // Same day
+
+	// Test all frequency types - day-of should always fire
+	for intervalDays := range FrequencySchedules {
+		t.Run(fmt.Sprintf("DayOf_Interval_%d", intervalDays), func(t *testing.T) {
+			var frequencyDays *int
+			if intervalDays > 0 {
+				frequencyDays = &intervalDays
+			}
+
+			stage := GetReminderStageForToday(dueDate, frequencyDays, today)
+			if stage != "day_of" {
+				t.Errorf("Day-of notification for interval %d: got %q, expected \"day_of\"",
+					intervalDays, stage)
+			}
+		})
+	}
+}
+
+// TestNoNotificationAfterMaxOverdue ensures no notifications after MaxOverdueDays
+func TestNoNotificationAfterMaxOverdue(t *testing.T) {
+	dueDate := time.Date(2025, 6, 15, 0, 0, 0, 0, time.UTC)
+	var frequencyDays *int // Once frequency
+
+	// Test days beyond MaxOverdueDays
+	for daysOverdue := OverdueConfig.MaxOverdueDays + 1; daysOverdue <= OverdueConfig.MaxOverdueDays+30; daysOverdue++ {
+		today := dueDate.AddDate(0, 0, daysOverdue)
+		stage := GetReminderStageForToday(dueDate, frequencyDays, today)
+
+		if stage != "" {
+			t.Errorf("Day %d overdue (beyond MaxOverdueDays=%d): should not send notification, but got %q",
+				daysOverdue, OverdueConfig.MaxOverdueDays, stage)
+		}
+	}
+}
+
+// TestNoNotificationTooFarInFuture ensures no notifications for tasks far in the future
+func TestNoNotificationTooFarInFuture(t *testing.T) {
+	dueDate := time.Date(2025, 6, 15, 0, 0, 0, 0, time.UTC)
+
+	// Get the maximum pre-reminder days from all schedules
+	maxPreReminderDays := 0
+	for _, schedule := range FrequencySchedules {
+		for _, days := range schedule {
+			if days > maxPreReminderDays {
+				maxPreReminderDays = days
+			}
+		}
+	}
+
+	// Test for each frequency type - days beyond their schedule should not trigger
+	for intervalDays, schedule := range FrequencySchedules {
+		t.Run(fmt.Sprintf("FarFuture_Interval_%d", intervalDays), func(t *testing.T) {
+			var frequencyDays *int
+			if intervalDays > 0 {
+				frequencyDays = &intervalDays
+			}
+
+			// Find the max reminder day for this frequency
+			maxForFrequency := 0
+			for _, d := range schedule {
+				if d > maxForFrequency {
+					maxForFrequency = d
+				}
+			}
+
+			// Test days beyond the max reminder day for this frequency
+			for daysBefore := maxForFrequency + 1; daysBefore <= maxPreReminderDays+10; daysBefore++ {
+				// Skip if this day is actually in the schedule
+				if slices.Contains(schedule, daysBefore) {
+					continue
+				}
+
+				today := dueDate.AddDate(0, 0, -daysBefore)
+				stage := GetReminderStageForToday(dueDate, frequencyDays, today)
+
+				if stage != "" {
+					t.Errorf("Day %d before due (beyond schedule max=%d for interval %d): should not send, but got %q",
+						daysBefore, maxForFrequency, intervalDays, stage)
+				}
+			}
+		})
+	}
+}
+
+// TestConfigConsistency validates that the configuration is internally consistent
+func TestConfigConsistency(t *testing.T) {
+	// Verify GetOverdueReminderDays matches ShouldSendOverdueReminder
+	overdueDays := GetOverdueReminderDays()
+
+	for day := 1; day <= OverdueConfig.MaxOverdueDays+5; day++ {
+		shouldSend := ShouldSendOverdueReminder(day)
+		isInList := slices.Contains(overdueDays, day)
+
+		if shouldSend != isInList {
+			t.Errorf("Inconsistency at day %d: ShouldSendOverdueReminder=%v, but day in GetOverdueReminderDays=%v",
+				day, shouldSend, isInList)
+		}
+	}
+
+	// Verify all frequencies have 0 (day-of) in their schedule
+	for intervalDays, schedule := range FrequencySchedules {
+		if !slices.Contains(schedule, 0) {
+			t.Errorf("Frequency %d days is missing day-of (0) in schedule: %v", intervalDays, schedule)
+		}
+	}
+
+	// Verify schedules are sorted in descending order (most days first)
+	for intervalDays, schedule := range FrequencySchedules {
+		for i := 0; i < len(schedule)-1; i++ {
+			if schedule[i] < schedule[i+1] {
+				t.Errorf("Frequency %d schedule is not in descending order: %v", intervalDays, schedule)
+				break
+			}
+		}
+	}
+}
+
+// TestStageFormatting validates the stage string formatting
+func TestStageFormatting(t *testing.T) {
+	testCases := []struct {
+		daysBefore    int
+		expectedStage string
+	}{
+		{0, "day_of"},
+		{1, "reminder_1d"},
+		{3, "reminder_3d"},
+		{7, "reminder_7d"},
+		{14, "reminder_14d"},
+		{30, "reminder_30d"},
+	}
+
+	for _, tc := range testCases {
+		t.Run(fmt.Sprintf("Format_%d_days_before", tc.daysBefore), func(t *testing.T) {
+			stage := formatDaysBeforeStage(tc.daysBefore)
+			if stage != tc.expectedStage {
+				t.Errorf("formatDaysBeforeStage(%d) = %q, expected %q", tc.daysBefore, stage, tc.expectedStage)
+			}
+		})
+	}
+
+	// Test overdue formatting
+	overdueTestCases := []struct {
+		daysOverdue   int
+		expectedStage string
+	}{
+		{1, "overdue_1"},
+		{3, "overdue_3"},
+		{7, "overdue_7"},
+		{14, "overdue_14"},
+	}
+
+	for _, tc := range overdueTestCases {
+		t.Run(fmt.Sprintf("Format_%d_days_overdue", tc.daysOverdue), func(t *testing.T) {
+			stage := formatOverdueStage(tc.daysOverdue)
+			if stage != tc.expectedStage {
+				t.Errorf("formatOverdueStage(%d) = %q, expected %q", tc.daysOverdue, stage, tc.expectedStage)
+			}
+		})
+	}
+}
+
+// BenchmarkGetReminderStageForToday benchmarks the main function
+func BenchmarkGetReminderStageForToday(b *testing.B) {
+	dueDate := time.Date(2025, 6, 15, 0, 0, 0, 0, time.UTC)
+	today := time.Date(2025, 6, 12, 0, 0, 0, 0, time.UTC) // 3 days before
+	intervalDays := 30
+	frequencyDays := &intervalDays
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		GetReminderStageForToday(dueDate, frequencyDays, today)
+	}
+}
+
+// TestReminderScheduleTableDriven uses the config to generate a comprehensive
+// table-driven test that validates all expected notification days
+func TestReminderScheduleTableDriven(t *testing.T) {
+	dueDate := time.Date(2025, 6, 15, 0, 0, 0, 0, time.UTC)
+
+	// Build test cases from config
+	for intervalDays, preSchedule := range FrequencySchedules {
+		var frequencyDays *int
+		if intervalDays > 0 {
+			frequencyDays = &intervalDays
+		}
+
+		freqName := FrequencyNames[intervalDays]
+		if freqName == "" {
+			freqName = fmt.Sprintf("Custom_%d", intervalDays)
+		}
+
+		// Test pre-due reminders
+		for _, daysBefore := range preSchedule {
+			t.Run(fmt.Sprintf("%s_PreReminder_%dd", freqName, daysBefore), func(t *testing.T) {
+				today := dueDate.AddDate(0, 0, -daysBefore)
+				stage := GetReminderStageForToday(dueDate, frequencyDays, today)
+				expected := formatDaysBeforeStage(daysBefore)
+
+				if stage != expected {
+					t.Errorf("got %q, expected %q", stage, expected)
+				}
+			})
+		}
+
+		// Test overdue reminders (same for all frequencies)
+		overdueDays := GetOverdueReminderDays()
+		for _, daysOverdue := range overdueDays {
+			t.Run(fmt.Sprintf("%s_Overdue_%dd", freqName, daysOverdue), func(t *testing.T) {
+				today := dueDate.AddDate(0, 0, daysOverdue)
+				stage := GetReminderStageForToday(dueDate, frequencyDays, today)
+				expected := formatOverdueStage(daysOverdue)
+
+				if stage != expected {
+					t.Errorf("got %q, expected %q", stage, expected)
+				}
+			})
+		}
+	}
+}
+
+// TestFullSimulation100Tasks is the main comprehensive test that simulates
+// 100 random tasks over the full date range
+func TestFullSimulation100Tasks(t *testing.T) {
+	// Use a fixed seed for reproducible tests
+	rng := rand.New(rand.NewSource(42))
+
+	// All available frequencies including custom
+	frequencies := []int{0, 1, 7, 14, 30, 90, 180, 365, 5, 10, 20, 45, 100, 200, 500}
+
+	baseDate := time.Date(2025, 6, 15, 0, 0, 0, 0, time.UTC)
+
+	// Statistics
+	totalDays := 0
+	totalNotifications := 0
+	notificationsByStage := make(map[string]int)
+
+	for taskIdx := 0; taskIdx < 100; taskIdx++ {
+		// Random frequency
+		intervalDays := frequencies[rng.Intn(len(frequencies))]
+
+		// Random due date (within 60-day range around base)
+		dueDateOffset := rng.Intn(61) - 30
+		dueDate := baseDate.AddDate(0, 0, dueDateOffset)
+
+		var frequencyDays *int
+		if intervalDays > 0 {
+			frequencyDays = &intervalDays
+		}
+
+		// Get expected schedules from config
+		preSchedule := GetScheduleForFrequency(frequencyDays)
+		overdueDays := GetOverdueReminderDays()
+
+		// Simulate 45 days before to 15 days after due date
+		for dayOffset := -45; dayOffset <= 15; dayOffset++ {
+			// dayOffset: negative = future (before due), positive = past (overdue)
+			// So if dayOffset = -10, we're 10 days BEFORE due date
+			// If dayOffset = 5, we're 5 days AFTER due date (overdue)
+			today := dueDate.AddDate(0, 0, dayOffset)
+			totalDays++
+
+			stage := GetReminderStageForToday(dueDate, frequencyDays, today)
+
+			// Calculate expected stage
+			var expectedStage string
+			if dayOffset < 0 {
+				// Before due date: check pre-reminders
+				daysBefore := -dayOffset
+				if slices.Contains(preSchedule, daysBefore) {
+					expectedStage = formatDaysBeforeStage(daysBefore)
+				}
+			} else if dayOffset == 0 {
+				// Day of
+				expectedStage = "day_of"
+			} else {
+				// Overdue
+				if slices.Contains(overdueDays, dayOffset) {
+					expectedStage = formatOverdueStage(dayOffset)
+				}
+			}
+
+			if stage != expectedStage {
+				t.Errorf("Task %d (freq=%d, due=%s): day %s (offset=%d): got %q, expected %q",
+					taskIdx+1, intervalDays, dueDate.Format("2006-01-02"),
+					today.Format("2006-01-02"), dayOffset, stage, expectedStage)
+			}
+
+			if stage != "" {
+				totalNotifications++
+				notificationsByStage[stage]++
+			}
+		}
+	}
+
+	t.Logf("Full Simulation Results:")
+	t.Logf("  Total tasks: 100")
+	t.Logf("  Total days simulated: %d", totalDays)
+	t.Logf("  Total notifications: %d", totalNotifications)
+	t.Logf("  Notifications by stage:")
+	for stage, count := range notificationsByStage {
+		t.Logf("    %s: %d", stage, count)
+	}
+}

internal/repositories/reminder_repo.go

@@ -0,0 +1,125 @@
+package repositories
+
+import (
+	"time"
+
+	"gorm.io/gorm"
+
+	"github.com/treytartt/casera-api/internal/models"
+)
+
+// ReminderRepository handles database operations for task reminder logs
+type ReminderRepository struct {
+	db *gorm.DB
+}
+
+// NewReminderRepository creates a new reminder repository
+func NewReminderRepository(db *gorm.DB) *ReminderRepository {
+	return &ReminderRepository{db: db}
+}
+
+// HasSentReminder checks if a reminder has already been sent for the given
+// task, user, due date, and reminder stage.
+func (r *ReminderRepository) HasSentReminder(taskID, userID uint, dueDate time.Time, stage models.ReminderStage) (bool, error) {
+	// Normalize to date only
+	dueDateOnly := time.Date(dueDate.Year(), dueDate.Month(), dueDate.Day(), 0, 0, 0, 0, time.UTC)
+
+	var count int64
+	err := r.db.Model(&models.TaskReminderLog{}).
+		Where("task_id = ? AND user_id = ? AND due_date = ? AND reminder_stage = ?",
+			taskID, userID, dueDateOnly, stage).
+		Count(&count).Error
+
+	if err != nil {
+		return false, err
+	}
+
+	return count > 0, nil
+}
+
+// LogReminder records that a reminder was sent.
+// Returns the created log entry or an error if the reminder was already sent
+// (unique constraint violation).
+func (r *ReminderRepository) LogReminder(taskID, userID uint, dueDate time.Time, stage models.ReminderStage, notificationID *uint) (*models.TaskReminderLog, error) {
+	// Normalize to date only
+	dueDateOnly := time.Date(dueDate.Year(), dueDate.Month(), dueDate.Day(), 0, 0, 0, 0, time.UTC)
+
+	log := &models.TaskReminderLog{
+		TaskID:         taskID,
+		UserID:         userID,
+		DueDate:        dueDateOnly,
+		ReminderStage:  stage,
+		SentAt:         time.Now().UTC(),
+		NotificationID: notificationID,
+	}
+
+	err := r.db.Create(log).Error
+	if err != nil {
+		return nil, err
+	}
+
+	return log, nil
+}
+
+// GetSentRemindersForTask returns all reminder logs for a specific task and user.
+func (r *ReminderRepository) GetSentRemindersForTask(taskID, userID uint) ([]models.TaskReminderLog, error) {
+	var logs []models.TaskReminderLog
+	err := r.db.Where("task_id = ? AND user_id = ?", taskID, userID).
+		Order("sent_at DESC").
+		Find(&logs).Error
+	return logs, err
+}
+
+// GetSentRemindersForDueDate returns all reminder logs for a specific task,
+// user, and due date.
+func (r *ReminderRepository) GetSentRemindersForDueDate(taskID, userID uint, dueDate time.Time) ([]models.TaskReminderLog, error) {
+	dueDateOnly := time.Date(dueDate.Year(), dueDate.Month(), dueDate.Day(), 0, 0, 0, 0, time.UTC)
+
+	var logs []models.TaskReminderLog
+	err := r.db.Where("task_id = ? AND user_id = ? AND due_date = ?",
+		taskID, userID, dueDateOnly).
+		Order("sent_at DESC").
+		Find(&logs).Error
+	return logs, err
+}
+
+// CleanupOldLogs removes reminder logs older than the specified number of days.
+// This helps keep the table from growing indefinitely.
+func (r *ReminderRepository) CleanupOldLogs(daysOld int) (int64, error) {
+	cutoff := time.Now().UTC().AddDate(0, 0, -daysOld)
+
+	result := r.db.Where("sent_at < ?", cutoff).
+		Delete(&models.TaskReminderLog{})
+
+	return result.RowsAffected, result.Error
+}
+
+// GetRecentReminderStats returns statistics about recent reminders sent.
+// Useful for admin/monitoring purposes.
+func (r *ReminderRepository) GetRecentReminderStats(sinceHours int) (map[string]int64, error) {
+	since := time.Now().UTC().Add(-time.Duration(sinceHours) * time.Hour)
+
+	stats := make(map[string]int64)
+
+	// Count by stage
+	rows, err := r.db.Model(&models.TaskReminderLog{}).
+		Select("reminder_stage, COUNT(*) as count").
+		Where("sent_at >= ?", since).
+		Group("reminder_stage").
+		Rows()
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	for rows.Next() {
+		var stage string
+		var count int64
+		if err := rows.Scan(&stage, &count); err != nil {
+			return nil, err
+		}
+		stats[stage] = count
+	}
+
+	return stats, nil
+}

internal/repositories/task_repo.go

@@ -50,6 +50,7 @@ type TaskFilterOptions struct {
 	PreloadAssignedTo  bool
 	PreloadResidence   bool
 	PreloadCompletions bool // Minimal: just id, task_id, completed_at
+	PreloadFrequency   bool // For smart notifications
 }
 
 // applyFilterOptions applies the filter options to a query.
@@ -88,6 +89,9 @@ func (r *TaskRepository) applyFilterOptions(query *gorm.DB, opts TaskFilterOptio
 			return db.Select("id", "task_id", "completed_at")
 		})
 	}
+	if opts.PreloadFrequency {
+		query = query.Preload("Frequency")
+	}
 
 	return query
 }
@@ -209,6 +213,32 @@ func (r *TaskRepository) GetCancelledTasks(opts TaskFilterOptions) ([]models.Tas
 	return tasks, err
 }
 
+// GetActiveTasksForUsers returns all active, non-completed tasks for the specified users.
+// This is used by the smart notification system to evaluate all tasks for potential reminders.
+// It includes tasks that are overdue, due soon, or upcoming - the caller determines
+// which reminders to send based on the task's frequency and due date.
+func (r *TaskRepository) GetActiveTasksForUsers(now time.Time, opts TaskFilterOptions) ([]models.Task, error) {
+	var tasks []models.Task
+
+	// Get all active, non-completed tasks
+	query := r.db.Model(&models.Task{}).
+		Scopes(task.ScopeActive, task.ScopeNotCompleted)
+
+	// Include in-progress tasks if specified
+	if !opts.IncludeInProgress {
+		query = query.Scopes(task.ScopeNotInProgress)
+	}
+
+	// Apply filters and preloads
+	query = r.applyFilterOptions(query, opts)
+
+	// Order by due date for consistent processing
+	query = query.Order("COALESCE(next_due_date, due_date) ASC NULLS LAST")
+
+	err := query.Find(&tasks).Error
+	return tasks, err
+}
+
 // === Task CRUD ===
 
 // FindByID finds a task by ID with preloaded relations

internal/worker/jobs/handler.go

@@ -12,6 +12,7 @@ import (
 
 	"github.com/treytartt/casera-api/internal/config"
 	"github.com/treytartt/casera-api/internal/models"
+	"github.com/treytartt/casera-api/internal/notifications"
 	"github.com/treytartt/casera-api/internal/push"
 	"github.com/treytartt/casera-api/internal/repositories"
 	"github.com/treytartt/casera-api/internal/services"
@@ -19,18 +20,21 @@ import (
 
 // Task types
 const (
-	TypeTaskReminder     = "notification:task_reminder"
+	TypeTaskReminder       = "notification:task_reminder"
-	TypeOverdueReminder  = "notification:overdue_reminder"
+	TypeOverdueReminder    = "notification:overdue_reminder"
-	TypeDailyDigest      = "notification:daily_digest"
+	TypeSmartReminder      = "notification:smart_reminder" // Frequency-aware reminders
-	TypeSendEmail        = "email:send"
+	TypeDailyDigest        = "notification:daily_digest"
-	TypeSendPush         = "push:send"
+	TypeSendEmail          = "email:send"
-	TypeOnboardingEmails = "email:onboarding"
+	TypeSendPush           = "push:send"
+	TypeOnboardingEmails   = "email:onboarding"
+	TypeReminderLogCleanup = "maintenance:reminder_log_cleanup"
 )
 
 // Handler handles background job processing
 type Handler struct {
 	db                   *gorm.DB
 	taskRepo             *repositories.TaskRepository
+	reminderRepo         *repositories.ReminderRepository
 	pushClient           *push.Client
 	emailService         *services.EmailService
 	notificationService  *services.NotificationService
@@ -49,6 +53,7 @@ func NewHandler(db *gorm.DB, pushClient *push.Client, emailService *services.Ema
 	return &Handler{
 		db:                  db,
 		taskRepo:            repositories.NewTaskRepository(db),
+		reminderRepo:        repositories.NewReminderRepository(db),
 		pushClient:          pushClient,
 		emailService:        emailService,
 		notificationService: notificationService,
@@ -553,3 +558,179 @@ func (h *Handler) HandleOnboardingEmails(ctx context.Context, task *asynq.Task)
 
 	return nil
 }
+
+// HandleSmartReminder processes frequency-aware task reminders.
+// Unlike the old HandleTaskReminder and HandleOverdueReminder, this handler:
+// 1. Uses frequency-based schedules (weekly = day-of only, annual = 30d, 14d, 7d, day-of)
+// 2. Tracks sent reminders to prevent duplicates
+// 3. Tapers off overdue reminders (daily for 3 days, then every 3 days, stop after 14)
+func (h *Handler) HandleSmartReminder(ctx context.Context, task *asynq.Task) error {
+	log.Info().Msg("Processing smart task reminders...")
+
+	now := time.Now().UTC()
+	today := time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, time.UTC)
+	currentHour := now.Hour()
+
+	// Use the task_due_soon hour setting for smart reminders
+	systemDefaultHour := h.config.Worker.TaskReminderHour
+
+	log.Info().
+		Int("current_hour", currentHour).
+		Int("system_default_hour", systemDefaultHour).
+		Msg("Smart reminder check")
+
+	// Step 1: Find users who should receive notifications THIS hour
+	var eligibleUserIDs []uint
+
+	query := h.db.Model(&models.NotificationPreference{}).
+		Select("user_id").
+		Where("task_due_soon = true OR task_overdue = true")
+
+	if currentHour == systemDefaultHour {
+		query = query.Where("task_due_soon_hour IS NULL OR task_due_soon_hour = ?", currentHour)
+	} else {
+		query = query.Where("task_due_soon_hour = ?", currentHour)
+	}
+
+	if err := query.Pluck("user_id", &eligibleUserIDs).Error; err != nil {
+		log.Error().Err(err).Msg("Failed to query eligible users for smart reminders")
+		return err
+	}
+
+	if len(eligibleUserIDs) == 0 {
+		log.Debug().Int("hour", currentHour).Msg("No users scheduled for smart reminders this hour")
+		return nil
+	}
+
+	log.Info().Int("eligible_users", len(eligibleUserIDs)).Msg("Found users eligible for smart reminders")
+
+	// Step 2: Query all active tasks for eligible users
+	opts := repositories.TaskFilterOptions{
+		UserIDs:            eligibleUserIDs,
+		IncludeInProgress:  true,
+		PreloadResidence:   true,
+		PreloadCompletions: true,
+		PreloadFrequency:   true,
+	}
+
+	// Get all active, non-completed tasks
+	activeTasks, err := h.taskRepo.GetActiveTasksForUsers(now, opts)
+	if err != nil {
+		log.Error().Err(err).Msg("Failed to query active tasks")
+		return err
+	}
+
+	log.Info().Int("count", len(activeTasks)).Msg("Found active tasks for eligible users")
+
+	// Step 3: Process each task
+	var sentCount, skippedCount int
+
+	for _, t := range activeTasks {
+		// Determine which user to notify
+		var userID uint
+		if t.AssignedToID != nil {
+			userID = *t.AssignedToID
+		} else if t.Residence.ID != 0 {
+			userID = t.Residence.OwnerID
+		} else {
+			continue
+		}
+
+		// Check if user is in eligible list
+		eligible := false
+		for _, eligibleID := range eligibleUserIDs {
+			if userID == eligibleID {
+				eligible = true
+				break
+			}
+		}
+		if !eligible {
+			continue
+		}
+
+		// Get the effective due date (NextDueDate takes precedence for recurring tasks)
+		var effectiveDate time.Time
+		if t.NextDueDate != nil {
+			effectiveDate = *t.NextDueDate
+		} else if t.DueDate != nil {
+			effectiveDate = *t.DueDate
+		} else {
+			// No due date, skip
+			continue
+		}
+
+		// Get frequency interval days
+		var frequencyDays *int
+		if t.Frequency != nil && t.Frequency.Days != nil {
+			days := int(*t.Frequency.Days)
+			frequencyDays = &days
+		} else if t.CustomIntervalDays != nil {
+			days := int(*t.CustomIntervalDays)
+			frequencyDays = &days
+		}
+
+		// Determine which reminder stage applies today
+		stage := notifications.GetReminderStageForToday(effectiveDate, frequencyDays, today)
+		if stage == "" {
+			continue // No reminder needed today
+		}
+
+		// Convert stage string to ReminderStage type
+		reminderStage := models.ReminderStage(stage)
+
+		// Check if already sent
+		alreadySent, err := h.reminderRepo.HasSentReminder(t.ID, userID, effectiveDate, reminderStage)
+		if err != nil {
+			log.Error().Err(err).Uint("task_id", t.ID).Msg("Failed to check reminder log")
+			continue
+		}
+
+		if alreadySent {
+			skippedCount++
+			continue
+		}
+
+		// Determine notification type based on stage
+		var notificationType models.NotificationType
+		if stage == "day_of" || (len(stage) >= 8 && stage[:8] == "reminder") {
+			notificationType = models.NotificationTaskDueSoon
+		} else {
+			notificationType = models.NotificationTaskOverdue
+		}
+
+		// Send notification
+		if err := h.notificationService.CreateAndSendTaskNotification(ctx, userID, notificationType, &t); err != nil {
+			log.Error().Err(err).Uint("user_id", userID).Uint("task_id", t.ID).Str("stage", stage).Msg("Failed to send smart reminder")
+			continue
+		}
+
+		// Log the reminder
+		if _, err := h.reminderRepo.LogReminder(t.ID, userID, effectiveDate, reminderStage, nil); err != nil {
+			log.Error().Err(err).Uint("task_id", t.ID).Str("stage", stage).Msg("Failed to log reminder")
+		}
+
+		sentCount++
+	}
+
+	log.Info().
+		Int("sent", sentCount).
+		Int("skipped_duplicates", skippedCount).
+		Msg("Smart reminder notifications completed")
+
+	return nil
+}
+
+// HandleReminderLogCleanup cleans up old reminder logs to prevent table bloat
+func (h *Handler) HandleReminderLogCleanup(ctx context.Context, task *asynq.Task) error {
+	log.Info().Msg("Processing reminder log cleanup...")
+
+	// Clean up logs older than 90 days
+	deleted, err := h.reminderRepo.CleanupOldLogs(90)
+	if err != nil {
+		log.Error().Err(err).Msg("Failed to cleanup old reminder logs")
+		return err
+	}
+
+	log.Info().Int64("deleted", deleted).Msg("Reminder log cleanup completed")
+	return nil
+}

migrations/010_add_task_reminder_log.down.sql

@@ -0,0 +1,5 @@
+-- Rollback: Smart Notification Reminder System
+
+DROP INDEX IF EXISTS idx_reminderlog_sent_at;
+DROP INDEX IF EXISTS idx_reminderlog_task_user_date;
+DROP TABLE IF EXISTS task_reminderlog;

migrations/010_add_task_reminder_log.up.sql

@@ -0,0 +1,24 @@
+-- Smart Notification Reminder System
+-- Tracks which reminders have been sent to prevent duplicates
+
+CREATE TABLE task_reminderlog (
+    id SERIAL PRIMARY KEY,
+    task_id INTEGER NOT NULL REFERENCES task_task(id) ON DELETE CASCADE,
+    user_id INTEGER NOT NULL REFERENCES auth_user(id) ON DELETE CASCADE,
+    due_date DATE NOT NULL,                              -- Which occurrence this is for
+    reminder_stage VARCHAR(20) NOT NULL,                 -- e.g., "reminder_30d", "reminder_7d", "day_of", "overdue_1", "overdue_4"
+    sent_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
+    notification_id INTEGER REFERENCES notifications_notification(id) ON DELETE SET NULL,
+
+    -- Prevent duplicate reminders for same task/user/date/stage
+    UNIQUE(task_id, user_id, due_date, reminder_stage)
+);
+
+-- Index for quick lookup when checking if reminder was already sent
+CREATE INDEX idx_reminderlog_task_user_date ON task_reminderlog(task_id, user_id, due_date);
+
+-- Index for cleanup job (delete old logs)
+CREATE INDEX idx_reminderlog_sent_at ON task_reminderlog(sent_at);
+
+COMMENT ON TABLE task_reminderlog IS 'Tracks sent task reminders to prevent duplicate notifications';
+COMMENT ON COLUMN task_reminderlog.reminder_stage IS 'Stage of reminder: reminder_30d, reminder_14d, reminder_7d, reminder_3d, reminder_1d, day_of, overdue_N';