DevSpend Pro

FinTechIntermediateJan 17, 2026

DevSpend Pro

Effortless project expense tracking for solo builders.

The Problem

Solo developers and indie hackers often juggle multiple projects, each with its own set of recurring subscriptions (SaaS tools, APIs, hosting), one-off purchases (themes, licenses), and even time-based costs. Tracking these expenses accurately and attributing them to specific projects for profitability analysis and tax purposes is a significant headache. Generic accounting software is often too complex and expensive, while spreadsheets become unwieldy and error-prone. This leads to wasted hours manually reconciling costs, inaccurate project profit assessments, and potential missed tax deductions. A builder might spend 2-3 hours monthly just on expense categorization, losing valuable development time and clarity on which projects are truly profitable, impacting their ability to scale or make informed business decisions.

The Solution

DevSpend Pro provides a focused solution for solo developers to easily log and attribute expenses to specific projects. Users can quickly add expenses, categorize them, and tag them to one or more ongoing projects. The unique value lies in its simplicity and developer-centric features: quick entry for common dev tools/subscriptions, intuitive project-based views, and basic profitability reports per project. Imagine seeing at a glance the total spend for 'Project X' and its net revenue. This allows builders to understand their true project costs, optimize their tech stack spend, and simplify tax preparation, freeing them up to build more.

Tech Stack

Frontend

Next.js 14ReactTailwind CSSshadcn/ui

Backend

Next.js API RoutesTypeScript

Database

PostgreSQL (Supabase)

APIs

Stripe (for subscriptions)Resend (for transactional emails)

System Architecture

┌─────────────────┐       ┌──────────────────────┐
  │     Client      │       │      External        │
  │ (Web Browser)   │       │      Services        │
  └───────┬─────────┘       └──────────┬───────────┘
          │ HTTP Request              │
          ▼                           │
  ┌─────────────────┐                 │
  │ Next.js Backend │                 │
  │  (API Routes)   │                 │
  ├─────────────────┤                 │
  │  Authentication │                 │
  │  Expense Logic  │                 │
  │  Project Logic  │                 │
  │  Reporting Logic│                 │
  └───────┬─────────┘                 │
          │                           │
          │ DB Queries                │
          ▼                           │
  ┌─────────────────┐                 │
  │    Supabase     │                 │
  │  (PostgreSQL)   │                 │
  ├─────────────────┤                 │
  │   users table   │                 │
  │  projects table │                 │
  │  expenses table │                 │
  │  categories table│                 │
  └─────────────────┘                 │
          ▲                           ▼
          │                           │
          │ Payment Gateway           │ Email Service
          │ (for SaaS subscription)   │ (transactional)
          │                           │
          │                           │
          │                           │
  ┌───────┴─────────┐       ┌────────┴──────────┐
  │     Stripe      │       │      Resend       │
  └─────────────────┘       └───────────────────┘

Database Schema

-- Users table for authentication
CREATE TABLE users (
  id UUID PRIMARY KEY REFERENCES auth.users(id) ON DELETE CASCADE,
  email TEXT UNIQUE NOT NULL,
  display_name TEXT,
  created_at TIMESTAMPTZ DEFAULT NOW(),
  updated_at TIMESTAMPTZ DEFAULT NOW()
);
CREATE INDEX users_email_idx ON users (email);
ALTER TABLE users ENABLE ROW LEVEL SECURITY;
CREATE POLICY "Users can view their own data." ON users FOR SELECT USING (auth.uid() = id);
CREATE POLICY "Users can update their own data." ON users FOR UPDATE USING (auth.uid() = id);

-- Projects table
CREATE TABLE projects (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
  name TEXT NOT NULL,
  description TEXT,
  status TEXT DEFAULT 'active' CHECK (status IN ('active', 'archived', 'completed')),
  revenue_model TEXT, -- e.g., 'SaaS', 'Consulting', 'One-time sale'
  expected_revenue DECIMAL(10, 2) DEFAULT 0.00,
  created_at TIMESTAMPTZ DEFAULT NOW(),
  updated_at TIMESTAMPTZ DEFAULT NOW()
);
CREATE INDEX projects_user_id_idx ON projects (user_id);
ALTER TABLE projects ENABLE ROW LEVEL SECURITY;
CREATE POLICY "Users can manage their own projects." ON projects FOR ALL USING (auth.uid() = user_id) WITH CHECK (auth.uid() = user_id);

-- Expense Categories table
CREATE TABLE expense_categories (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
  name TEXT UNIQUE NOT NULL, -- e.g., 'Hosting', 'SaaS Subscriptions', 'API Costs', 'Marketing'
  created_at TIMESTAMPTZ DEFAULT NOW()
);
CREATE INDEX expense_categories_user_id_idx ON expense_categories (user_id);
ALTER TABLE expense_categories ENABLE ROW LEVEL SECURITY;
CREATE POLICY "Users can manage their own categories." ON expense_categories FOR ALL USING (auth.uid() = user_id) WITH CHECK (auth.uid() = user_id);

-- Expenses table
CREATE TABLE expenses (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
  project_id UUID REFERENCES projects(id) ON DELETE SET NULL, -- Can be null if general expense
  category_id UUID REFERENCES expense_categories(id) ON DELETE SET NULL,
  amount DECIMAL(10, 2) NOT NULL,
  currency TEXT DEFAULT 'USD' NOT NULL,
  description TEXT,
  transaction_date DATE NOT NULL,
  is_recurring BOOLEAN DEFAULT FALSE,
  recurrence_interval TEXT, -- e.g., 'monthly', 'annually'
  vendor TEXT,
  receipt_url TEXT,
  created_at TIMESTAMPTZ DEFAULT NOW(),
  updated_at TIMESTAMPTZ DEFAULT NOW()
);
CREATE INDEX expenses_user_id_idx ON expenses (user_id);
CREATE INDEX expenses_project_id_idx ON expenses (project_id);
CREATE INDEX expenses_category_id_idx ON expenses (category_id);
ALTER TABLE expenses ENABLE ROW LEVEL SECURITY;
CREATE POLICY "Users can manage their own expenses." ON expenses FOR ALL USING (auth.uid() = user_id) WITH CHECK (auth.uid() = user_id);