SaaS Pegasus is the most credible Python full-stack starter — Django + PostgreSQL + Celery + REST API + AI chat, $499 one-time. CleenUI ships 14 production domain modules on ASP.NET Core 8 with a 300-table stored-procedure-first data layer.
SaaS Pegasus earns the 'CTO in a box' label within the Python ecosystem. It's a genuine full-stack starter: Django 5 backend, PostgreSQL database, Celery async tasks, Django REST Framework, React or HTMX frontend, Stripe, multi-tenant teams, an AI chat module, and Wagtail CMS. Well-maintained, actively updated — the first choice for Python-first teams who don't want to start from zero. The comparison with CleenUI isn't which is better — it's which runtime fits your team and how much of the application ships on day one. SaaS Pegasus ships the SaaS chassis: auth, teams, billing, email, background jobs, CMS. CleenUI ships the chassis plus 10 additional production domain modules — help center, translations, notifications, messaging, task management, AI model operations, assessments, marketplace — on ASP.NET Core 8 with 524 pre-built endpoints and a 300+ table Azure SQL schema.
| Category | CleenUI | SaaS Pegasus |
|---|---|---|
| Runtime | .NET 8 / ASP.NET Core 8 | Python 3 / Django 5.x |
| Database | Azure SQL — 300+ tables, 700+ stored procedures, Dapper + ADO.NET (no ORM) | PostgreSQL — Django ORM, code-first migrations, 20–30 tables (users, teams, subscriptions, content) |
| API layer | 524 pre-built endpoints across 20 modules and 25 functional groupings | Django REST Framework — REST API you build endpoint by endpoint |
| Background jobs | 12-project .NET solution: 3 Azure Functions + 2 WebJobs + 6 shared libraries (translation, media safety, video encoding, thumbnails) | Celery — task queue pre-wired with Redis; you write the workers |
| Frontend | React 18 SPA — 61 accessible components in 12 categories, Storybook documented | React 19 or HTMX + TailwindCSS (your choice at project setup) |
| Domain modules | 14 production vertical modules: auth, accounts, help center, observability, translations, notifications, messaging, tasks, AI ops, fonts, legal, taxonomy, assessments, marketplace | Auth, teams/multi-tenancy, Stripe billing + e-commerce, CMS (Wagtail), AI chat, feature flags — no messaging, no assessments, no marketplace |
| AI capabilities | M09 — 6-vendor LLM routing with percentage control, prompt versioning + restore, AI agent lifecycle, HeyGen avatar video integration | AI chat/agents (any LLM via the AI SDK), Claude + Cursor rules files included |
| Real-time | SignalR hub — conversations, participants, presence, reactions, read receipts, draft state, media (M07) | Django Channels (WebSocket) available — no pre-built messaging system |
| Pricing | Custom-scoped per engagement — starts with a no-cost 30-minute architecture review with the architect | $449–$499 one-time (Professional/Unlimited), 1 year updates included |
These capabilities are pre-built in CleenUI. SaaS Pegasus has no equivalent — you'd build them from scratch or wire a third-party integration.
M01–M20: auth, accounts, help center, observability, translations, notification templates, real-time messaging, task management, AI model operations, font management, legal policies, taxonomy, assessment instruments, and vendor marketplace. SaaS Pegasus ships auth, teams, billing, CMS, and AI chat — five infrastructure modules, no vertical domain modules.
700+ hand-crafted Azure SQL stored procedures via Dapper + ADO.NET — no ORM, no migration-generated schema. SaaS Pegasus uses Django ORM with PostgreSQL migrations. The stored-procedure pattern gives data teams explicit SQL control and auditable execution plans with no leaky abstraction.
A production-tested REST API surface: 524 endpoints across 20 modules and 25 functional groupings. SaaS Pegasus provides Django REST Framework infrastructure; the endpoint count is however many you've built on top of it.
M07 Messaging: conversations, participants, presence indicators, reactions, read receipts, draft state, media attachments — pre-built end to end. SaaS Pegasus ships Django Channels for WebSocket support; the messaging protocol and all application-layer logic are yours to write.
3 Azure Functions (translation queue, media safety scanning, video encoding) + 2 WebJobs (translation sweep, thumbnail generation) + 6 shared C# class libraries — domain-specific async workers, pre-wired. SaaS Pegasus ships Celery infrastructure; the workers are yours to write.
Pick SaaS Pegasus when your team is Python-first and Django is non-negotiable — it's the best-maintained full-stack Django starter available. Also reach for it when $499 fits your budget and you're comfortable building domain modules in-house, when Celery is your preferred async stack, or when the React-or-HTMX flexibility suits a team still deciding on the UI layer.
Pick CleenUI when your team runs .NET or you need a C# API with an owned SQL database. Also pick it when domain modules need to ship pre-built — if your product will include a help center, multilingual content, real-time messaging, assessments, or a marketplace, CleenUI ships those; SaaS Pegasus gives you Django and Celery to build them. And pick it when a stored-procedure-first data layer with 300+ pre-designed tables is the right foundation for your data model.