diff --git a/CLAUDE.md b/CLAUDE.md
new file mode 100644
index 0000000..4a9b7dc
--- /dev/null
+++ b/CLAUDE.md
@@ -0,0 +1,102 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Build and Test Commands
+
+### Building
+```bash
+# Build the executable
+go build -o dave.exe
+
+# Download dependencies
+go mod download
+```
+
+### Testing
+```bash
+# Run all tests
+go test ./tests/...
+
+# Run a specific test file
+go test ./tests/calculator_test.go
+
+# Run a specific test function
+go test -run TestCalculateMonthlyInterest ./tests/
+```
+
+### Running
+```bash
+# Run the built executable
+./dave.exe
+
+# Or run directly with go
+go run main.go
+```
+
+## Project Architecture
+
+Dave is a CLI debt tracking tool built with Go using the Cobra command framework and SQLite for persistence.
+
+### Core Package Structure
+
+- **`main.go`**: Entry point that delegates to `cmd.Execute()`
+- **`cmd/`**: Cobra command definitions (add, pay, remove, adjust-*, mode, snowball, reset, show)
+  - `root.go`: Base command setup, database initialization lifecycle, and command registration
+  - Each command file defines a single Cobra command
+- **`internal/models/`**: Data models and database operations
+  - `debt.go`: Debt CRUD operations with support for position-based (#) or name-based lookup
+  - `payment.go`: Payment history tracking
+  - `settings.go`: User settings (sort mode, snowball amount)
+- **`internal/database/`**: SQLite database wrapper and schema management
+  - `db.go`: Database connection wrapper
+  - `schema.go`: Table creation and schema initialization
+- **`internal/calculator/`**: Financial calculation engine
+  - `interest.go`: Monthly interest calculations
+  - `projections.go`: Simulates monthly payments with compound interest to project payoff timelines
+- **`internal/display/`**: Terminal UI rendering with Lipgloss
+  - `table.go`: Debt table formatting with ASCII art header
+  - `formatter.go`: Currency, date, and percentage formatting utilities
+  - `styles.go`: Lipgloss style definitions
+- **`internal/config/`**: Configuration and path management
+  - `paths.go`: Database path resolution (`~/.dave/debts.db`)
+
+### Key Architecture Patterns
+
+**Database Lifecycle**: The database connection is initialized in `cmd/root.go`'s `init()` via Cobra's `OnInitialize` hook and closed in `PersistentPostRun`. All commands access the shared DB via `GetDB()`.
+
+**Dual Identifier System**: Most commands accept either a position number (1, 2, 3...) or creditor name. The `GetDebtByIndexOrName()` function handles this by attempting integer parsing first, then falling back to name lookup.
+
+**Sort Modes**: Three modes control debt ordering:
+- `snowball`: Smallest balance first (psychological wins)
+- `avalanche`: Highest APR first (mathematically optimal)
+- `manual`: Custom ordering via `custom_order` column
+
+Mode changes are handled in `models/settings.go` and affect how `GetAllDebts()` sorts results.
+
+**Projection Algorithm** (`calculator/projections.go`):
+The `ProjectPayoffTimeline()` function simulates month-by-month payments:
+1. Apply monthly interest to all active debts
+2. Apply minimum payments to all active debts
+3. Apply snowball amount to highest-priority unpaid debt
+4. When a debt is paid off, add its minimum payment to the snowball (auto-snowball)
+5. Repeat for up to 600 months (50 years) or until all debts are paid
+
+This simulation accounts for compound interest and the cascading snowball effect.
+
+**Hidden Paid Debts**: Debts with `current_balance = 0` are automatically filtered out by `GetAllDebts()` (via `WHERE current_balance > 0`), but remain in the database for historical tracking.
+
+**Payment History**: The `payments` table tracks all payments with interest/principal breakdown. When recording a payment, the debt balance is updated and a payment record is inserted.
+
+## Data Storage
+
+SQLite database at `~/.dave/debts.db` with three tables:
+- **debts**: id, creditor, original_balance, current_balance, apr, minimum_payment, custom_order (nullable), created_at, updated_at
+- **payments**: id, debt_id (FK), amount, interest_paid, principal_paid, payment_date, created_at
+- **settings**: key-value pairs (sort_mode, snowball_amount)
+
+## Dependencies
+
+- **Cobra**: CLI framework for command structure
+- **Lipgloss**: Terminal UI styling and table rendering
+- **modernc.org/sqlite**: Pure-Go SQLite driver (no CGo)
diff --git a/internal/display/formatter.go b/internal/display/formatter.go
index 7208083..316721d 100644
--- a/internal/display/formatter.go
+++ b/internal/display/formatter.go
@@ -3,14 +3,16 @@ package display
 import (
 	"fmt"
 	"time"
+
+	"github.com/dustin/go-humanize"
 )
 
 // FormatCurrency formats a float as currency with comma separators
 func FormatCurrency(amount float64) string {
 	if amount < 0 {
-		return fmt.Sprintf("-$%.2f", -amount)
+		return "-$" + humanize.CommafWithDigits(amount*-1, 2)
 	}
-	return fmt.Sprintf("$%.2f", amount)
+	return "$" + humanize.CommafWithDigits(amount, 2)
 }
 
 // FormatPercent formats a float as a percentage
diff --git a/internal/display/table.go b/internal/display/table.go
index 9646c26..95bb0c9 100644
--- a/internal/display/table.go
+++ b/internal/display/table.go
@@ -70,7 +70,15 @@ func RenderDebtsTable(debts []models.Debt, projections []calculator.DebtProjecti
 	t := table.New().
 		Border(lipgloss.NormalBorder()).
 		BorderStyle(lipgloss.NewStyle().Foreground(lipgloss.Color("8"))).
-		Headers("#", "Creditor", "Original", "Current", "Rate", "Payment", "Interest", "Payoff", "Months", "Years")
+		Headers("#", "Creditor", "Original", "Current", "Rate", "Payment", "Interest", "Payoff", "Months", "Years").
+		StyleFunc(func(row, col int) lipgloss.Style {
+			style := lipgloss.NewStyle()
+			// Right-align numeric columns (all except #=0 and Creditor=1)
+			if col >= 2 {
+				style = style.Align(lipgloss.Right)
+			}
+			return style
+		})
 
 	// Add data rows
 	for i, debt := range debts {