See all servicesWeb Application Security
Vlad Sedenko · Web Product Developer

Service / Independent specialist

Find and fix security risks before they become incidents

A product can look finished while weak access control, exposed keys or an unsafe form quietly puts customer data and the business at risk. I review the application as a senior developer, explain the findings in business terms and fix the issues in the code instead of stopping at a report.
  • Authentication, roles and permissions checked against real user flows
  • Exposed secrets, unsafe inputs and vulnerable dependencies identified
  • Production configuration, cookies, headers and admin routes reviewed
  • Prioritized remediation with verification after the fixes
Get a quote for your project

/ Fit

Who this is for

  • Founders preparing a website, SaaS product or AI-built prototype for launch

  • Teams handling accounts, payments, personal data or internal business information

  • Companies that inherited a codebase and do not know its current security posture

  • Products that need practical remediation rather than a report nobody implements

/ The review

What the security review covers

Authentication and sessions

Login, password reset, session expiry, cookies and account recovery.

Authorization and access control

Roles, tenant isolation, admin routes and protection against users accessing another user's data.

Input and data handling

Validation, file uploads, forms and common injection or cross-site scripting risks.

Secrets and configuration

API keys, environment variables, debug settings, CORS, security headers and production exposure.

Dependencies and integrations

Vulnerable packages, webhook verification, third-party APIs and payment-related flows.

Operational safeguards

Rate limiting, logging, error handling, backups and a clear list of residual risks.

/ Deliverables

What you receive

A prioritized report with severity, business impact and reproducible evidence; a remediation plan ordered by risk and effort; hands-on fixes for the agreed scope; and a verification pass showing what was resolved and what still requires attention.

/ Process

How it works

  1. Scope

    We identify the application, sensitive flows, environments and access needed for the review.

  2. Review

    I inspect the code, configuration and critical user journeys using manual checks and appropriate tooling.

  3. Prioritize

    Findings are ranked by realistic risk, business impact and remediation effort.

  4. Fix and verify

    I implement the agreed changes and re-test the affected flows before handover.

10+

years in web development

120+

launched projects

24h

reply, EU-based

Request a security review

Send me the product URL, stack and the flows that handle accounts, payments or sensitive data. I will reply within 24 hours with the right scope and next step.

I reply within 24 hours. You'll talk to me directly, not a sales team.

Frequently asked questions

Who is Web Application Security for?

Web Application Security is for founders, small businesses and teams that need hands-on work on a website or web product, not just high-level recommendations.

How does the engagement start?

We start with a short description of your goal, current state and constraints. I then suggest the scope, priorities, next steps and a realistic delivery model.

Do you implement recommendations in code?

Yes. I work as a developer, so I can not only prepare a plan but also implement changes in code, site structure, integrations and configuration.

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