API security is non-negotiable whether you’re a startup or an enterprise. As more applications rely on backend services to handle sensitive information, access control, and core operations, the exposure to attacks grows significantly. Hiring a contract backend specialist can be a economical way to develop or refactor your API, but it’s not enough to just find someone who is technically proficient. You need someone who builds with security-first principles.

Outline meticulously your API’s function and the type of data it will handle. If you’re dealing with personal information, payment data, аренда персонала or HIPAA-regulated information, you must comply with relevant regulations like PCI-DSS. A experienced specialist will clarify regulatory obligations immediately and embed compliance into the structure. They should know how to structure endpoints to limit unnecessary access and prevent data exposure through debug outputs or sensitive HTTP fields.

Proper auth is your frontline protection. Make sure your developer implements current industry standards like JWT with proper token expiration and secure re-authentication. Avoid basic username and password authentication over unencrypted connections. Mandate secure transport and enforce it with HSTS headers. A security-aware dev will implement client-side token protection on the frontend and re-authenticate each API invocation on the backend.

Request sanitization are often ignored. Even the well-structured endpoint can be exploited if it accepts untrusted data. Your developer should apply strict schema rules using strict schemas and reject anything that doesn’t match. They should also use prepared statements to defend against query tampering and escape output to mitigate client-side injection.

Rate limiting and logging are vital for detecting and preventing abuse. A specialist should enforce API quotas to block credential stuffing. Logging should record anomalies without retaining passwords or tokens. Make sure logs are encrypted at rest and archived periodically to reduce the risk of exposure.

Maintain your package inventory. Many breaches happen because of vulnerable dependencies. A security-conscious engineer will leverage SCA tools and keep packages updated. They should also avoid including unnecessary third party code that could create unforeseen attack surfaces.

Testing is mandatory. The developer should write unit and integration tests that simulate attack scenarios. They should also simulate real-world exploits or at least simulate common attack vectors. If they’re lack experience with vulnerability scanners, it’s a warning sign.

When hiring a freelance backend developer, request case studies of secured systems. Inspect their codebase and analyze their token handling, data encryption practices, and failure state handling. Conduct a thorough evaluation even if you’re following a referral. Security isn’t a task; it’s a philosophy.

Building a secure API takes time. It requires continuous monitoring and forward-thinking safeguards. By choosing a specialist who embeds security into code and working closely with them to define your needs, you can build an API that’s not just efficient but also secure-by-design.