UBIKON.ioBackend
Backend & API Development
Typical engagement: $8k–$40k · 4–10 weeks
What this is
Ubikon builds fast, documented, tested APIs on FastAPI, PostgreSQL and MongoDB that mobile and web teams can build against on day one — typed request/response models, real test coverage, and API documentation that's actually current. A typical engagement runs $8k–$40k across 4–10 weeks.
What you get
Concrete deliverables, not a vague promise.
- —A typed API with request/response validation on every endpoint (Pydantic or Zod)
- —Automatically generated, always-current API documentation
- —Test coverage on business logic — not just a smoke test that the server starts
- —CI/CD, monitoring, and rate limiting on every public-facing route
- —Full IP transfer and private repository handover
How we build it
Stack and architecture for a typical build.
FastAPI and Python for the API layer, PostgreSQL for relational data or MongoDB when the shape genuinely calls for a document model, and Docker for consistent environments from local dev through production.
Pricing
Where the number comes from.
The $8k–$40k range above is priced from real delivery data across 300+ completed projects — not a day rate multiplied by a guess. A full itemized breakdown by phase is available on a scoping call, or get a rough one now from the calculator below.
Open the cost calculator →The honest comparison
PostgreSQL vs MongoDB for a typical product backend
Both are correct choices in the right context — here is how we decide.
| PostgreSQL (Ubikon default) | MongoDB | |
|---|---|---|
| Relational data, complex queries | Strong fit | Workable, often awkward at scale |
| Rapidly-changing, document-shaped data | Workable via JSONB | Native fit |
| Transactional integrity | Strong, ACID by default | Supported, less central to the model |
| Best fit | Most product backends — billing, users, relational business data | Content stores, logs, flexible-schema data |
Process
4–10 weeks, start to launch.
Scope the data model
What the API actually needs to represent, before any endpoint is written.
Fixed quote, 48 hours
Priced by endpoint count and complexity of the business logic behind them.
Weekly builds
A staging API with live docs you can hit yourself every week.
Launch with monitoring
Rate limiting and uptime alerting live from day one.
Straight answers
What buyers ask about this service
How much does a custom API cost? +
Most backends run $8,000–$40,000, priced by endpoint count and the complexity of the business logic and integrations behind them, not a flat day rate.
PostgreSQL or MongoDB — which do you recommend? +
PostgreSQL by default for most product backends, since relational integrity and complex queries usually matter more than people expect once a product has real users. MongoDB when the data is genuinely document-shaped and rapidly changing, like content or logs.
Do you provide API documentation? +
Yes, generated from the typed schema so it stays current automatically rather than drifting out of sync with the code, which is the usual failure mode of hand-written API docs.
Related
Other services worth a look
One call. One fixed number.
Tell us about your backend & api development project.
30 minutes, no deck. A fixed quote follows within 48 hours.