EidenTech can scope backend services for a new interface, an existing product, or a workflow connected to external tools. We start with the actions and records your business needs, then define contracts, persistence, permissions, and operating behaviour. A useful API makes success, pending work, and failure understandable to every consuming application.
How we approach your project
Define contracts around real application actions
Map the interface journeys to the backend operations they require. A request to publish a product, qualify a lead, or confirm an order needs an explicit input, permitted caller, business rule, and result. We agree required fields, identifiers, pagination, and error categories before the frontend depends on undocumented responses. Existing consumers influence compatibility and versioning decisions. The contract should distinguish a completed operation from work accepted for later processing, so the interface does not tell a customer that an external action has finished when it remains pending.
Check authority where the data is used
Authentication establishes an identity, while authorisation decides whether that identity may perform a particular action on a particular record. Both belong in the backend design. We review roles, tenant or account boundaries, server-side validation, and the fields a client may change. A hidden button is not an access control. Integration credentials remain outside the browser, and privileged operations receive an appropriate permission boundary. If a workflow needs approvals or an activity record, those requirements are part of the action model rather than an interface detail added later.
Keep business state consistent
Identify related changes that must succeed together and the records that establish the source of truth. Database transactions can protect local invariants; they do not automatically include an external payment or CRM request. We review identifiers, permitted status transitions, duplicate requests, and the way concurrent actions are handled. For longer work, a durable job may be more suitable than keeping a browser request open. The user-facing state should explain what is complete and what needs follow-up, with reconciliation responsibilities defined for interrupted or uncertain operations.
Integrate with providers without hiding failure
External APIs introduce authentication, quotas, timeouts, and response formats the application does not control. We review provider documentation and a test environment before connecting live customer data. Field mapping, bounded retries, and repeated notifications need deliberate behaviour. Some actions are safe to repeat while others require a stable request identifier or a lookup before retrying. The backend should return useful feedback to the interface and provide operational evidence for the team. A fluent AI reply or a successful network connection alone is not proof that the intended business record was saved.
Deliver an API that can be maintained
Testing covers important contracts, permissions, state transitions, and dependency failures using representative test records. We consider request sizes, expensive queries, and expected concurrency when planning performance. Logging should help trace errors without publishing confidential fields. Handover includes configuration, endpoint documentation, deployment responsibilities, and the procedure for changing a contract. If multiple clients use the API, rollout decisions account for their update cycles. The goal is a backend whose rules and failure behaviour remain understandable as the product develops.
What we can deliver
We agree the requirements and responsibilities before development begins. Your project scope can include:
- An API and business-action contract with required fields, responses, and compatibility assumptions.
- Backend implementation for the agreed records, permissions, and state transitions.
- Persistence and supported provider integrations with defined timeout and retry behaviour.
- Meaningful contract, access, and failure-path checks using suitable test data.
- Endpoint documentation and configuration, release, and operating guidance.
Technology choices for your requirements
The stack follows your integrations, operating model, and maintenance needs. These are options to review during discovery, rather than a fixed stack promised for every project.
- Node.js and TypeScript with Next.js server endpoints or Fastify where appropriate
- PostgreSQL persistence, migrations, and transaction boundaries suited to the workflow
- Provider-supported REST APIs, webhooks, and background-processing tools
Planning questions, answered
Can you build an API for an existing frontend?
Yes. We review its journeys, request assumptions, authentication, and error handling before defining the contract. Existing screens can remain where they fit, while missing validation or unclear state transitions become part of the backend scope.
Can one backend support a website and mobile app?
Yes, where the required workflows can share suitable contracts. We account for differences in client versions, session behaviour, device needs, and update timing so the API does not assume every client changes at once.
Can you connect payments, logistics, or AI providers?
We can scope supported provider connections after reviewing documentation, credentials, business actions, and operating constraints. Transaction updates, repeated events, customer permissions, and failed requests need explicit handling rather than a simple connection alone.
How do you decide which operations need background jobs?
We review completion time, dependency reliability, retry needs, and the user’s expected feedback. Work that must survive a process restart may need durable persistence and a worker, with a visible pending state and an owner for failures.
Tell us what needs to work better.
Share your idea, existing workflow, and the outcome you need. We will help shape a practical starting point.
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