Home/Services/Backend API & Infrastructure
Service · 03 · Development

Backends any frontend can build against.

Standalone REST or GraphQL API development: documented, tested and production-deployed, with the runtime chosen for what your service needs.

Last reviewed · 1 Oct 20264 primary sources →Kalenux engineering
Share your API spec →How a request flows
INTERFACEREST or GraphQL
DOCSFull OpenAPI
ENGAGEMENTProject-based
openapi.yaml · API reference
GET/ordersPOST/ordersGET/orders/{id}PATCH/orders/{id}POST/auth/refresh
POST/v1/ordersCreate an order. Requires a bearer token.
{ "customer_id": "cus_8f2a", "items": [ … ]}
201Created400Validation error401Unauthorised429Rate limited
illustrative excerpt
we build the server side on its own

Your frontend, our backend.

Backend-only projects are common. We build the API independently and document it fully, so any frontend team can work against it without having to ask how it behaves.

The frontend already exists
Existing web app⇅Kalenux API
We plug in behind it
Another team is building the UI
Partner UI team⇅Kalenux API
They build against the OpenAPI spec
A mobile app needs an API
iOS / Android app⇅Kalenux API
One API, many clients
the runtime is chosen per service
High throughputWhen latency and request volume matter most
Rapid deliveryWhen speed of shipping matters and your team already knows the language
Data-heavyWhen the model is complex and the queries are heavily relational
// request lifecycle

Everything a request passes through.

The full server-side scope, in the order a real request meets it.

01 →RequestClient call
02 →Rate limitPer endpoint & user
03 →AuthJWT · OAuth 2.0 · API keys
04 →ValidationAt the API boundary
05 →CacheExpensive queries
06 →DatabaseIndexed, optimised queries
07ResponseConsistent errors · logged
// what you get

Deliverables and outcomes

GET /handover → 200 · 8 items
GET/handover/docs200
OpenAPI documentationEvery endpoint documented with request parameters, response schemas, error codes and example payloads. Importable into any API client.
GET/handover/auth200
Authenticated endpointsJWT-based authentication with access and refresh token rotation, or API-key authentication for machine-to-machine use. OAuth 2.0 for third-party login providers.
GET/handover/schema200
Database schema and migrationsEntity-relationship design, properly indexed tables, and migration files that apply to any environment cleanly.
GET/handover/cache200
Caching layerResponse caching for expensive queries, rate-limiting enforcement and session storage, with cache invalidation tied to data mutation events.
GET/handover/errors200
Input validation and error handlingAll inputs validated at the API boundary with structured error responses; error codes and messages consistent across all endpoints.
GET/handover/security200
Rate limiting and security headersPer-endpoint and per-user rate limiting. Security headers (CORS, CSP, HSTS) configured for the deployment environment.
GET/handover/deploy200
Containerised deploymentThe API is containerised, with a local development setup and production-equivalent environment parity.
GET/handover/load200
Load testing and performance baselineBefore handover, basic load tests establish a performance baseline and identify bottlenecks under expected traffic.
+30 days of post-launch supportincluded with every development project · see Services
how we work

The contract is agreed before any code is written.

Your frontend team gets a stable target from day one, and scope can't drift halfway through the project.

# contract v1, agreed before any code
paths:
/orders/{id}:
get:
security: [bearerAuth]
responses:
200: { $ref: Order }
404: { $ref: Error }
429: { $ref: RateLimited }
  1. a1f3c9API contract designEndpoints, schemas, auth model, error format
  2. b72e04Database schemaEntities, indexes, migration strategy
  3. c90d1aImplementationEndpoints, auth, validation, caching
  4. d4418fIntegration testingEvery endpoint tested against the contract
  5. e05b77Load testingBaseline set, bottlenecks resolved
  6. f6c2e8Deploy + handoverLive in production, OpenAPI docs delivered
The contract and commit IDs are illustrative.
in depth · 4 primary sources

The specifications our APIs follow.

The standards and published guidance behind how we deliver this service, with every claim linked to its source.

01Documented with OpenAPI

Each endpoint is described in the OpenAPI Specification, a vendor-neutral format for describing HTTP APIs that tools can read and test [1].

02Correct HTTP semantics

Methods, status codes and caching follow RFC 9110, the current HTTP semantics standard [2]. Rate limits return 429 Too Many Requests, defined in RFC 6585 [3].

KEY FACTRFC 9110 (2022) replaced the older RFC 7231 as the definition of HTTP semantics [2].

03API security

Access control and data exposure are reviewed against the OWASP API Security Top 10, where broken object-level authorisation is the top risk [4].

References

  1. [1]OpenAPI Specification · OpenAPI Initiativespec.openapis.org/oas/latest.html
  2. [2]RFC 9110: HTTP Semantics · IETF, 2022www.rfc-editor.org/rfc/rfc9110
  3. [3]RFC 6585: Additional HTTP Status Codes (429) · IETF, 2012www.rfc-editor.org/rfc/rfc6585
  4. [4]OWASP API Security Top 10 · OWASP Foundationowasp.org/API-Security/
CITE THIS PAGEKalenux. (2026). Backend API & microservices service. Kalenux SEO Guide. Last reviewed 1 Oct 2026. kalenux.com.tr/service/backend-api
// start a backend project

Need a backend API built?

Share the API requirements or a rough spec and we’ll design the data model and endpoint structure before we start coding.

Get in touch →@emirbaycan@kalenux.com.tr
WHAT HAPPENS NEXT
1
Within one business dayA real reply from an engineer, not an automated queue.
2
Architecture proposalData model and endpoint structure, designed before any code.
3
TimelineA step-by-step plan through to production launch.
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