Perne
Custom backend and API development: illustration 1
Websites

Custom backend and API development

We work as a team to build the server side of your project: the database, the business logic, user authorisation and an API through which a front end, a mobile app or external services get data. We write in Python with Django or FastAPI, store data in PostgreSQL, describe endpoints in Swagger/OpenAPI and cover the core logic with tests. Work is paid by the agreed scope, so we first fix the list of endpoints and data models.

from 80,000 ₸ (≈ $160) one-off

timeline: 10–25 working days

  • Designing data models and the relations between them against an agreed schema
  • An API with user authorisation and access roles
  • Endpoint descriptions in Swagger/OpenAPI for the front end and integrations

Order

Message on WhatsApp
TelegramCall

The service name is added to the message for you.

This is a starting price; we give the final amount before work starts. USD is approximate.

What is included

  • Designing data models and the relations between them against an agreed schema
  • An API with user authorisation and access roles
  • Endpoint descriptions in Swagger/OpenAPI for the front end and integrations
  • PostgreSQL data storage with migrations and schema backups
  • Tests of the core logic and API with Pytest or the framework's own tools
  • Deployment to your server or hosting with Docker, if agreed
  • Handover of the code in your repository and a short guide for developers

Who it is for

For companies and startups that need their own server logic, an integration with a website, app or accounting systems, and who are ready to describe the task as a list of functions. It does not fit if you need a ready-made site builder or a one-off setup without programming: other services cover that.

Not included

To avoid surprises, here is what the base price does not cover and what is discussed separately:

  • Developing a mobile app or front end, unless agreed separately
  • Expanding the scope after the endpoint list is agreed, without a new estimate
  • Payment for servers, cloud services and licences the project needs

How the work goes

  1. 1

    Discovery call

    We talk through your business, your customers and what the site has to do. Everything is online: a video call, WhatsApp or Telegram.

  2. 2

    Structure and price

    We agree the list of pages and features, the price and the timeline in a written agreement. 50% is paid upfront.

  3. 3

    Design and build

    We build the site in parts and share a preview link, so changes are easy to make while the work is in progress.

  4. 4

    Launch and handover

    We publish the site, connect your domain and show you how to edit texts and prices. The remaining 50% is paid after delivery.

FAQ

After payment the code and the rights to it belong to you, and it is handed over into your repository. We use open-source libraries under their licences and list them in the documentation. Our internal templates that we do not hand over do not enter the project without your knowledge.

The price includes two rounds of edits after the first working version of the API: refining fields, error codes and access rights. Adding new endpoints or changing the architecture is estimated separately and agreed before work starts.

Usually 10 to 25 working days, depending on the number of entities and the complexity of the logic. We first agree the list of endpoints and the data schema, and after that we name an exact date and a staged delivery plan.

A description of the task, the list of functions and user scenarios, sample data, security and load requirements, and access to the repository and server if you already have them. It helps to name the third-party services you need to integrate with, along with their documentation.

Most often we use Python with Django REST Framework or FastAPI, PostgreSQL, Redis for queues and caching, and Docker for running. This set is reliable and easy to maintain, and it is simpler to find a developer to continue the project than one for rare technologies.

We protect endpoints with authorisation, limit the number of requests from one address, validate all incoming data and do not return extra fields. Secrets are kept in environment variables, not in code. Full protection against attacks cannot be guaranteed, so after launch we recommend a security audit.

Yes, if the site can send requests to an external API. Before we start we look at the current data structure and decide whether a migration is needed, or whether the API will work alongside the current database. If the site is built on a constructor without code access, the integration may be limited.

You may also need

Custom web app and client portal

Custom web app and client portal

A browser-based tool with logins, client and staff accounts, requests and reports.

from 100,000 ₸ (≈ $200) one-off

Timeline: timeline: 20–40 working days

API integration between your services

API integration between your services

We connect your site, shop, CRM, payments and messengers so data moves between them on its own.

from 22,000 ₸ (≈ $44) one-off

Timeline: timeline: 5–10 working days

Testing: manual and automated tests

Testing: manual and automated tests

We test your website or app by hand and write automated tests, so bugs are found before your customers see them.

from 30,000 ₸ (≈ $60) one-off

Timeline: timeline: 3–10 working days

Shall we discuss your project?

The product name and a link to this page are filled into the WhatsApp message for you.

Message on WhatsApp
TelegramCall

Or send a request

We will reply in the channel you choose: WhatsApp, Telegram, phone or email. Your contact is used only to reply.

Service
How to reply

from 80,000 ₸ (≈ $160) one-off

Message on WhatsAppTelegramCall