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6.5
6.5
80%

NATORE, Bangladesh
$40 USD per hour
Toriqul Global Solutions is a professional web design and development company dedicated to building modern, high-performance, and user-friendly digital solutions. Founded by Engineer Md. Toriqul Islam, a Computer Science & Engineering graduate from RUET, the company brings over 10 years of experience in delivering scalable and visually appealing websites. Web Design & development: We are a full-stack web developer with more than 10 years of experience. Our design approach is always Modern and simple, which attracts people towards it. We have built websites for a wide variety of industries. We have worked with a lot of companies and built astonishing websites. All Clients have good reviews about me. Client Satisfaction is my first Priority. Technologies We Use: Custom Websites Development Using ======>Full Stack Development. 1. HTML5 2. CSS3 3. Bootstrap4 4. jQuery 5. JavaScript 6. Angular JS 7. React JS 8. Node JS 9. WordPress 10. PHP 11. Ruby on Rails 12. MYSQL 13. Laravel 14. .Net 15. CodeIgniter 16. React Native 17. SQL / MySQL 18. Mobile app development 19. Python 20. MongoDB and many other skills Why Choose Us: * Modern, clean, and user-focused design approach * Fully responsive across all devices * Scalable and reusable code structure * Clean, optimized, and well-documented code * On-time delivery with strict commitment to deadlines * Clear and professional communication * 100% client satisfaction is our priority We have successfully worked with clients across different industries, delivering high-quality websites that meet both business goals and user expectations. Let’s Build Something Great Together. Contact us today to discuss your project and turn your ideas into reality. Best Regards, Toriqul Global Solutions

7.6
7.6
91%

VAISHALI, India
$25 USD per hour
More than 08 years of experience in Software development, huge experience in building mobile app & web solution. I delivered more than 300 Mobile apps and Web solutions base on Java/J2EE related stacks to various client across the world. I am very strong in developing REST API using Spring Boot, JAX-RS or Jboss REST Easy. I worked as back-end engineer for many web/mobile app project so know well FCM/APNS push notification services, Twilio SMS API and collaborating with Front-end/Mobile app developer. I worked for Android(Java/Kotlin), iOS, Hybrid app (Flutter/React native), PHP(Laravel, Codeigniter) , Java, Java Swing, JavaFX, Spring Boot, REST, C# with APS .NET . Cloud platform like Google, Azure, Digital Ocean, AWS and many local hosting provider. Integrating various hardware devices to Mobile or Desktop app eg. RFID, NFC Reader, Bar code reader, Receipt printer, Bluetooth keyboard . I also work on customising Unicenta POS system. Apart form that I have also strong hands on Android (Java.Kotlin) Based Mobile apps with Hybrid experience Flutter or React Native. These are not limitation I am open for any new project with any tech-stack.

7.4
7.4
95%

Benediktbeuern, Germany
$64 USD per hour
Senior Systems & Security Engineer with 15+ years in enterprise-grade IT. I design, harden, and operate high-availability infrastructure, and I streamline delivery with automation and clean processes. My focus: reliability, security, and clear documentation—so changes are low-risk and handovers are effortless. Strengths: Infrastructure architecture & operations (Linux/Windows, virtualization, networking) Security hardening, identity & access, monitoring/observability Automation & DevOps practices (CI/CD, config management, IaC) PowerAutomate and Microsot 365 Migrations and upgrades with minimal downtime Concise runbooks, risk-aware planning, and stakeholder-friendly communication Certifications: CompTIA Security+, Microsoft MCSE/MCSA/MCITP Languages: English (C2), German (C1), native Romanian Location: Germany • NDA-friendly • Reliable and responsive

7.5
7.5
97%

Dhaka, Bangladesh
$120 USD per hour
If your web application, API, or AI system has vulnerabilities, attackers will find them. My job is to find them first. I'm Md Shofiur, a Certified Ethical Hacker (CEH) and senior penetration tester with 8+ years securing applications and infrastructure across fintech, healthcare, e-commerce, and SaaS. I've completed 87 projects on Freelancer with a 4.9 rating, a 97% on-budget record, and a 94% acceptance rate. I'm a member of the Preferred Freelancer Program and fully verified across payment, phone, email, and identity. 🎯 What I test Web applications using OWASP Top 10 methodology. REST and GraphQL APIs, covering authentication flaws, injection, IDOR, and rate limiting issues. AI-powered applications and LLM systems tested against the full OWASP LLM Top 10. WordPress, Laravel, and custom CMS platforms. Network and VPS infrastructure. PCI DSS, HIPAA, and ISO 27001 compliance environments. 🔍 What makes my work different I don't run a scanner and call it a pentest. Every engagement starts with manual reconnaissance, follows a structured methodology, and ends with a report your developers can actually act on. Each finding includes a risk rating, business impact, step-by-step proof of concept, and specific remediation guidance, not just a list of CVEs. 🤖 AI security testing I'm one of the few penetration testers on Freelancer offering dedicated security assessments for AI systems. If your company runs an LLM-powered chatbot, AI agent, or RAG system, I test it against the OWASP LLM Top 10, covering prompt injection, data extraction, insecure output handling, and excessive agency. ✅ Compliance experience PCI DSS v4.0 external and internal penetration testing. HIPAA security rule technical safeguard assessments. ISO/IEC 27001 security control validation. SOC 2 readiness penetration testing support. 🏆 Certifications Certified Ethical Hacker (CEH), API Penetration Testing, API Security for PCI Compliance, ISO/IEC 27001 Information Security Associate, Certified in Cybersecurity. 📋 What you get from every engagement An executive summary for management, a technical findings section with full proof of concept for each vulnerability, risk ratings using industry-standard scoring, and a prioritized remediation roadmap your team can follow immediately. ⚡ Response time I respond within 4 hours and offer a free 15-minute discovery call before any engagement starts. Send me your project details and I'll tell you exactly what I'd find and how I'd approach it

7.9
7.9
99%

Dhaka, Bangladesh
$55 USD per hour
Founded on a passion for solving complex business challenges through technology, OrFactor has delivered mission-critical solutions for clients in 25+ countries, including the USA, UK, Canada, Australia, Germany, France, the Netherlands, and Norway. Over the years, we’ve grown into a global team of 70+ specialized engineers with a 100% project completion rate — we finish what we start. Our expertise spans custom software development, enterprise integration, cloud transformation, DevOps, and data-driven digital solutions, all managed with precision, transparency, and a results-first mindset. From startups to Fortune 500 enterprises, our mission remains simple: build scalable, high-impact solutions that help clients innovate faster, reduce risk, and achieve measurable success. ⚡ Why Clients Trust Us ✅ 70+ specialized engineers • 21 years experience • 500+ projects delivered ✅ ZERO abandonment—100% completion guarantee ✅ Free 1-hour consultation • Dedicated PM • Daily updates ✅ 1 month FREE maintenance • NDA ready • 100% code ownership ✅ Deliver 2 weeks early (average) • Crystal-clear English • 24/7 support 💼 Our Expertise ✅ Custom Website Development ✅ Mobile App Development ✅ E-commerce Solutions ✅ Enterprise Software & SaaS ✅ API Development & Integration ✅ Cloud Infrastructure & DevOps ✅ AI/ML Integration ✅ UI/UX Design ✅ CMS & Content Platforms ✅ Database Design & Optimization ✅ Security & Compliance ✅ Maintenance & Support 🛠️ Technical Stack Frontend: React • Next.js • Vue.js • Angular • TypeScript • Tailwind CSS • Bootstrap Backend: Node.js • Python (Django) • PHP (Laravel) • Java (Spring Boot) • .NET Core • Ruby on Rails • Perl Mobile: Flutter • React Native • iOS (Swift) • Android (Kotlin) Database: PostgreSQL • MySQL • MongoDB • Redis • Firebase Cloud/DevOps: AWS • Google Cloud • Azure • Docker • Kubernetes AI/ML: OpenAI/Claude API • TensorFlow • Custom Chatbots Security: OWASP • GDPR • PCI-DSS • HIPAA Your project deserves a partner who cares. Whether you're launching a startup, scaling a business, or transforming operations—we're here to make it happen. Team OrFactor | Your Partner in Engineering Excellence Since 2004

5.9
5.9
65%

NATORE, Bangladesh
$10 USD per hour
Top Rated Freelancer ⭐⭐⭐⭐⭐ 5 Star Developer ⭐⭐⭐⭐⭐ 100% Job Success Hello and welcome! I'm a skilled full-stack developer with a passion for delivering high-quality work to my clients. With over 10 years of experience in web development, I specialize in building dynamic and engaging web applications using various technologies. I am an expert in web development and Mobile app development. I have worked on a wide variety of projects including CRM, Educational Platforms, Dashboards, Chat apps, Delivery apps, and more. My skills include: • HTML/CSS • JavaScript • Bootstrap • Tailwind CSS • JQuery • VueJS • ReactJS • PHP • Laravel • Python • Swift • C# • Rust • Perl • Ruby on Rails • Livewire • REST APIs • Payment integration • Database Design • SQL databases • Linux • SEO • Sopify • Docker • Laravel Forge • Objective-C • Java • Kotlin • React Native As a freelancer, I am committed to providing excellent communication and delivering top-notch work within your deadline. Whether you need a brand new web application developed from scratch or an existing one improved, I have the skills and experience necessary to get the job done. Some of the services I can provide include: ✅ Front-end web development ✅ Back-end web development ✅ Full-stack web development ✅ Converting design to HTML & CSS ✅ Custom API development ✅ Third-party API integration ✅ Database design and implementation ✅ Web application optimization and performance tuning My clients have described me as excellent developer and perfect communicator, and I strive to maintain this level of excellence in all my work. If you are looking for a dedicated and skilled full-stack web developer who can deliver exceptional work, please don't hesitate to contact me. I am confident that I can help you achieve your goals and exceed your expectations.
5.7
5.7
100%

ASHOK NAGAR, India
$25 USD per hour
With 15+ years of experience in software application development, I have worked with Avaya, Pramati, CGI, Yash, GMS, Vcentric, Meta-io, CTI Services, and MMTex. My core strengths are problem-solving, algorithms, system design, and building high-performance, low-latency systems for complex real-time workloads. I specialize in efficient coding, performance optimization, scalable architectures, and event-driven systems. Over the past 8+ years, I have led teams delivering trading, fintech, SaaS, AI/ML, automation, and IoT-based platforms. I am an AI/ML expert with deep experience in algorithmic trading, AI-driven signal generation, predictive analytics, reinforcement learning, NLP, and market regime detection. I work with Python, TensorFlow, PyTorch, Scikit-Learn, backtesting engines, walk-forward optimization, portfolio/risk-based position sizing, WebSockets, FIX, tick-level data, and order books. I also have experience in OMS/EMS, smart order routing, PnL/drawdown control, kill-switch mechanisms, blockchain/DeFi trading, automation bots, and cybersecurity including VAPT, secure coding, and API/network/cloud security. Mobile App Development ✅ Trading & fintech mobile apps with real-time data, charts, and alerts ✅ Flutter, React Native, Swift, Kotlin ✅ Secure APIs, backend integration, CI/CD, monitoring ✅ App Store / Play Store deployment and performance tuning Web & IoT / Embedded Systems ✅ IoT dashboards, device monitoring, telemetry, and real-time tracking ✅ Sensor data processing and hardware-to-software integration ✅ MQTT, WebSockets, REST APIs, serial communication, CAN/RS485 ✅ Edge device integration, alerts, logging, and cloud connectivity Frameworks ✅ Spring, Django, FastAPI, Laravel, ASP.Net, Nest.js, Next.js, Nuxt.js, React, Vue, Angular, Web3.js Backend Development ✅ Java, Python, Node.js, PHP, Laravel, ASP.Net, Go, Ruby, C++ ✅ Async systems, message queues, real-time processing Frontend & UI ✅ JavaScript, TypeScript, React & Redux, Vue, Angular, SCSS, Webpack, performance optimization Databases ✅ MySQL, PostgreSQL, Oracle, SQL Server, Cassandra, CouchDB ✅ Time-series and high-frequency data handling ✅ Supabase, Firebase, Firestore DevOps, Cloud & Infra ✅ Docker, Git, SonarQube, JMeter, Selenium ✅ AWS, Google Cloud, Azure, OpenStack ✅ Linux/Unix, Nginx, Apache, Tomcat, SSL ✅ High-availability, failover, monitoring Architecture ✅ Microservices, SOA, Event-Driven & Distributed Systems Portfolio & Live Applications GitHub https://github.com/viz-centric https://github.com/firee321/public.moneybox.au IoT / Hardware / Inspection Reference https://github.com/johibkhan2/Multi-Recorder https://pordoinspect.com/ Live Applications https://www.moneybox.au https://appwise.net.au/ https://pordoinspect.com/ https://serbob.com/

4.6
4.6
100%

Lahore, Pakistan
$30 USD per hour
I help businesses build scalable backend systems, Agentic AI solutions, and intelligent automation using Java, Spring Boot, and ATG (Oracle Commerce). With 8+ years of experience and 30+ successful freelance projects (5⭐ rating), I turn complex requirements into efficient, production-ready systems that save time and reduce operational costs. 💡 What You Can Expect Automation that reduces manual work and improves efficiency Backend systems that handle real-world scale and traffic Clean, maintainable code that lowers long-term costs Fast issue resolution and clear communication 🚀 Core Expertise Java, Spring Boot, Spring MVC ATG (Oracle Commerce) development REST APIs & microservices architecture AWS (EC2, RDS, Elastic Beanstalk) Database design & optimization (Oracle, MySQL, MS SQL) JSP, Servlets, HTML5, CSS3, JavaScript ⚡ Advanced Capabilities Agentic AI systems & LLM-based automation Workflow automation & process optimization IBM MQ, JMS integrations (enterprise systems) Docker & DevOps workflows Monitoring (New Relic, Sumo Logic) 🏆 Proven Track Record ✔ 30+ completed projects with consistent 5⭐ feedback ✔ Published research in AI (Pattern Recognition) ✔ Strong experience across backend, frontend & databases 🎯 What I Can Help You With Build AI-powered automation tools Develop or scale your web application Fix performance bottlenecks Integrate APIs and third-party systems Maintain and improve legacy Java/ATG platforms 🤝 Let’s Work If you need a developer who combines AI, automation, and solid engineering, I’m ready to help. Send me a message with your requirements—I’ll suggest the best approach before we start.

5.7
5.7
94%

Bngalore, India
$70 USD per hour
I am a Software Architect with 14+ years of experience I have worked mostly with early stage start-ups in which I was involved in the end to end product development cycle. Co-founded an AI based interview platform for initial screening of candidates. I tried creating a platform for group buying of NFTs from opensea. It was shortlisted for YC Summer 2022. I have also created an app for small shops to manage their inventory and billing which works offline as well. I am strong in algorithms and data structures and have solved a few complex real life problems at my work using algorithms Languages and Frameworks - BackEnd - Java (SpringBoot, Micronaut, Vert.x) - GoLang (Beginner) - Node.js - NoSQL and SQL - Elastic Search, Redis - Kafka, SQS, NATS - Docker - Kubernates - AWS - Prometheus/Victoria Metrics - Grafana Thanks Rajit
A Spring Security developer is a Java engineer who designs, implements, and hardens authentication and authorization layers in Spring-based applications using the Spring Security framework. Hiring a skilled Spring Security developer protects your application from unauthorized access, credential theft, session hijacking, and broken access control vulnerabilities that rank among the most common causes of data breaches. These specialists combine deep knowledge of the Spring ecosystem with practical security engineering, covering everything from OAuth2 and JWT-based authentication to method-level authorization, CSRF protection, and secure password storage.
A Spring Security freelancer configures and customizes the security layer of Java applications built on Spring Boot, Spring MVC, or Spring WebFlux. Their work covers identity, access, and protection concerns across REST APIs, microservices, and traditional web applications.
Typical deliverables include:
A capable Spring Security consultant is fluent across the broader Spring and Java security ecosystem. Expect proficiency with the following:
Demand for Spring Security expertise is strongest in industries where regulatory compliance and data sensitivity are non-negotiable. Common sectors include:
The strongest Spring Security developers combine framework fluency with a security mindset. Look for portfolio evidence of production-grade authentication flows, OAuth2 server or resource server implementations, and integrations with enterprise identity providers. Public contributions to Spring projects, security-focused blog posts, or CVEs reported in open source projects are strong signals.
Qualifications worth weighting include a Java or computer science background, Oracle Certified Professional Java SE credentials, and security-specific certifications such as CISSP, OSCP, or the Certified Secure Software Lifecycle Professional (CSSLP). Practical experience with the OWASP Top 10 and an ability to read threat models matter as much as framework knowledge.
Sample interview questions you can use directly:
Freelancer.com gives you access to a global pool of vetted Java and Spring specialists, from independent contractors hardening a single API to senior security architects redesigning enterprise identity systems. You can compare profiles, portfolios, certifications, and verified client reviews in one place, then receive competitive bids matched to your scope. Whether you need a short engagement to fix a vulnerability or a long-term security partner for a microservices platform, freelancers on Freelancer.com cover every level of seniority and every time zone. Milestone Payments protect your budget, and the platform's chat, file sharing, and time tracking keep complex security work auditable from start to finish.
Ready to secure your Java application against modern threats?
Hiring a Spring Security developer works best when your brief reflects the realities of your stack and threat model. The clearer you are about your Spring version, identity provider, and authorization requirements, the higher the quality of the bids you will receive. The process below walks you from posting the project to awarding the engagement.
Your project post is the single biggest determinant of bid quality, and a clear brief filters out candidates whose skills do not match. For Spring Security work, that means naming your Spring and Java versions, the type of authentication and authorization you need, and the identity providers or token formats involved. Head to the
Bids are short proposals that reveal how the freelancer has interpreted your brief, what approach they propose, and what timeline they consider realistic. Read carefully and shortlist candidates whose understanding of authentication, authorization, and the Spring filter chain matches the work you need done. A strong Spring Security proposal references specific framework features, not just generic security language.
The final decision combines proposal quality with profile evidence: portfolio, ratings, written client reviews, and verified credentials. Weight consistency of quality across multiple past Spring or Java security projects, not just one impressive example. For security work, look for evidence that the freelancer documents their changes and writes tests, because security regressions are easy to introduce and hard to spot.
A focused task such as adding JWT authentication to an existing REST API or migrating password hashing can take a few days. A full OAuth2 implementation with custom flows, identity provider integration, and method-level authorization across a microservices estate is usually a multi-week engagement. The freelancer should give you a realistic estimate after reviewing your codebase.
Yes. Many Spring Security experts on Freelancer.com offer fixed-scope audits that include a code review of your security configuration, threat modeling, OWASP Top 10 testing, and a prioritized remediation report. This is a common starting point before deciding whether to engage the same freelancer for the fixes.
A general Java developer can write business logic and basic Spring Boot code, but security configuration is a specialized area where mistakes cause breaches. A Spring Security developer focuses on authentication, authorization, cryptographic correctness, session and token management, and the framework's filter chain internals. For anything beyond default form login, you want the specialist.
For a defined scope, such as integrating Keycloak, building an OAuth2 authorization server, or remediating findings from a penetration test, a skilled freelancer is usually faster and more cost-effective. Agencies make more sense when you need ongoing security governance across multiple products and teams. Many clients start with a freelancer and scale up only if the work expands.
Most can advise on the client side of an OAuth2 or OIDC flow, including PKCE, silent refresh, and secure token storage in single-page applications built with React, Angular, or Vue. If the frontend work is substantial, confirm their experience with your specific framework before awarding the project.

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