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I need a production-ready software extension that plugs into a leading U.S. web portal and lets authenticated users reserve time slots. The core feature is straightforward—secure appointment booking—but I still expect a polished flow: user login, calendar view, slot validation against my internal rules, and a clean confirmation page. Because my previous developer left mid-stream, I’m only interested in someone who has built a similar portal integration before and can prove it with a demo or code sample. You’ll be inheriting some partial work, so quick comprehension and the ability to refactor are essential. Tech stack is flexible as long as you can deliver clean, well-documented code and a simple deployment script. Once the extension runs smoothly on the target portal, we’ll wrap up with a brief hand-off session so my in-house admin can manage future slot parameters on their own. If you have verifiable experience creating login-protected appointment tools for U.S. portals, let’s talk timeline and milestones right away.
Project ID: 40552944
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73 freelancers are bidding on average ₹51,871 INR for this job

Hi, I will deliver the appointment scheduler extension with secure login, calendar view, slot validation against your internal rules, and a clean confirmation page, all ready to plug into the target portal. Since you are inheriting partial work from a previous developer, I will start by auditing the existing codebase and refactoring what is needed before building forward. On a similar portal integration, I found that validating slots on the server side (not just the UI) eliminated double bookings entirely. I will apply that same pattern here, along with a deployment script and a hand-off session so your admin can manage slot parameters independently. Questions: 1) What state is the partial codebase in, and where is it hosted (GitHub, etc.)? Looking forward to your response. Best regards, Kamran
₹41,707 INR in 13 days
8.6
8.6

Hello, I can help with your "USA Portal Appointment Scheduler" project. I build clean, maintainable PHP backends — core PHP and Laravel/Symfony, MySQL schema design, and well-structured REST APIs. For work involving php, javascript, website design, css, html, software development, web development, api development, I pay close attention to validation, security, and readable code, delivering in small, testable milestones. You'll get clean commits and clear documentation. Could we discuss the specifics before I firm up the timeline? ⭐ 5.0/5 from a recent client: "Very Professional and On time delivery of the project" Final timeline and cost will be confirmed in chat after a complete understanding and documentation of the project expectations in detail.
₹60,000 INR in 13 days
7.6
7.6

I am an expert in Shopify, WordPress, and Web Development Technologies, ready to deliver a polished appointment booking software extension tailored to your needs. With proven experience in similar portal integrations, I guarantee clean and well-documented code. I can start RIGHT AWAY to ensure we meet timelines effectively. Regards, Pooja
₹56,250 INR in 3 days
7.1
7.1

Your partial codebase likely has authentication gaps or race conditions in the slot-booking logic that will cause double-bookings once you go live. If multiple users click the same time slot within milliseconds, your database will accept both reservations unless you've implemented row-level locking or optimistic concurrency control. Quick question - what's your current authentication method (OAuth, SAML, or custom session tokens), and are you enforcing slot expiration rules to prevent users from holding reservations indefinitely without confirming? Here's the architectural approach: - PHP/JAVASCRIPT: Refactor existing code to implement atomic slot reservation using database transactions with SELECT FOR UPDATE to prevent race conditions during concurrent bookings. - API DEVELOPMENT: Build RESTful endpoints for slot availability checks, reservation creation, and cancellation with proper HTTP status codes and error handling that your admin portal can consume. - HTML/CSS: Design a responsive calendar interface with real-time slot availability updates using AJAX polling or WebSocket connections to reflect bookings made by other users instantly. - SOFTWARE DEVELOPMENT: Write deployment scripts with environment-specific configs, database migration files, and rollback procedures so your admin can push updates without breaking production. I've built three similar appointment systems for healthcare portals that handle 500+ daily bookings without conflicts. One client had the exact double-booking issue you're facing - fixed it by adding Redis-based distributed locks. Let's schedule a 15-minute call to review your existing code structure and map out a 2-week completion timeline.
₹50,630 INR in 21 days
7.3
7.3

Greetings, Creating a secure appointment scheduler that integrates seamlessly with your U.S. web portal is crucial for enhancing user experience. I understand the importance of having a polished flow from user login to slot confirmation, especially since you have some existing work that needs to be refactored and completed. To tackle this project, I would focus on the following: 1. **User Authentication**: Implement a robust login system to ensure only authorized users can access the scheduling feature. 2. **Calendar Integration**: Develop a user-friendly calendar view that allows for easy slot selection, while rigorously validating against your internal rules. 3. **Clean Code and Documentation**: Deliver well-structured, thoroughly documented code along with a straightforward deployment script for smooth hand-off to your in-house admin. I’m excited to discuss how we can bring this project to fruition while ensuring your requirements are fully met.
₹37,500 INR in 14 days
6.2
6.2

I’ve built secure appointment schedulers integrated into U.S. portals before, including user login flows with slot validation that matched client rules. From your description, I understand you need a clean, production-ready extension that fits into an existing portal and supports user authentication, calendar view, slot checks, and confirmation pages. Since you have partial code and want fast onboarding, I’d start by reviewing what’s done and mapping out missing pieces or refactoring needs to ensure stability. Could you share how your internal slot validation rules are currently implemented? Are they on the backend or managed via the portal’s API? This will help define integration points and any customization. I’ll deliver clean, documented code with a simple deployment script, and I can prepare a quick admin guide for your team to update slot parameters independently once live. If you want, I can show a demo from a similar project to speed confidence. Ready to dive in and get this working smoothly—let me know when you’d like to start discussing milestones.
₹75,000 INR in 7 days
6.1
6.1

As an AI-based software development firm with a strong emphasis on SaaS platforms, Web Crest is well-equipped to handle the intricacies of your project. We have a proven and verifiable track record in developing login-protected appointment tools for leading web portals, reinforcing our ability to meet your specific needs. Our team’s skillset includes API Development, CSS, HTML, PHP, Software Development, Web Development, and Website Design which perfectly aligns with your project requirements. In addition to our technical expertise, we prioritize delivering clean, well-documented code for easy manageability and future scalability. This manifests in our proficiency with a range of tech stacks which gives us the flexibility to adapt to your preferred one. Moreover, we stay up-to-date with best practices in deployment and have simplified scripting to ensure seamless integration with your target portal. Efficiency is the hallmark of our work ethic and it’s precisely what you need right now as you’re handling partial work from the previous developer. Our quick comprehension skills combined with the ability to refactor will enable us to understand your project swiftly and provide an optimal solution. Ultimately, with Web Crest as your partner, you'll receive not just a satisfactory product aligned with your vision but also long-term technical support for smooth operations going forward.
₹50,000 INR in 3 days
6.5
6.5

Hi, I can take over your existing project and deliver a production-ready appointment booking extension that integrates smoothly with your target U.S. web portal. I'm experienced in working with partially completed codebases, quickly understanding existing architecture, refactoring where necessary, and delivering stable, maintainable solutions without disrupting ongoing functionality. The extension will provide a complete booking workflow, including secure user authentication, an intuitive calendar interface, real-time slot availability validation based on your business rules, conflict prevention, and a clean booking confirmation process. I'll begin by reviewing the current implementation, identifying gaps and technical debt, then complete the remaining functionality using clean, well-documented code and best development practices. I'm available to start immediately! Thanks, Pavan
₹45,000 INR in 20 days
6.1
6.1

Hi, I reviewed **USA Portal Appointment Scheduler** and I'm confident I can deliver exactly what you're looking for. With hands-on experience in **PHP, JavaScript, Website Design, Web Development, API Development**, I build professional, scalable, and user-focused solutions that are designed for performance and growth. I believe in clear communication, quality work, and on-time delivery. I'd love to discuss your project and share ideas that can add even more value. View some of my previous work: Looking forward to hearing from you.
₹60,000 INR in 14 days
5.9
5.9

Quality development, clear communication, and on-time delivery are what I bring to every project. After reviewing your requirements, I'm confident I can complete your appointment booking extension, integrate it seamlessly with the existing portal, and deliver a secure, production-ready solution with clean, maintainable code. I have experience working with existing codebases, authentication systems, scheduling workflows, and API integrations. I'll quickly understand the current implementation, refactor where necessary, and build a reliable booking flow featuring secure login, calendar-based scheduling, slot validation, and confirmation pages. The final solution will include well-documented source code, a simple deployment process, and a smooth handover so your team can easily manage booking rules and availability in the future. Before we get started, I'd like to clarify a few details: Which U.S. portal will the extension integrate with, and what technology stack is the existing project built on? Is there an existing appointment module that needs to be completed, or will it be developed from scratch? Also, does the portal expose APIs for authentication and scheduling, or will the extension integrate directly with the current application? Regards, Solves Inn
₹40,000 INR in 5 days
5.2
5.2

Hi there, We will build your portal appointment scheduler: secure login, calendar view, slot validation, and confirmation page. We will also refactor the partial codebase your previous developer left behind. For slot validation, we will run checks server-side against your internal rules before writing to the database. This prevents race conditions where two users grab the same slot. The calendar will poll for availability in real time so users only see open windows. A couple of quick things to confirm: 1) What state is the existing partial code in (framework, language, repo access)? 2) Are your internal slot rules time-based, role-based, or both? The number quoted here is a starting estimate. The exact cost and timeline will be confirmed after we go through the full scope together. Looking forward to your response. Best regards, Faizan
₹42,841 INR in 13 days
5.7
5.7

Hello, I’m interested in your project and confident I can deliver a secure, production-ready appointment booking extension. I have 5+ years of experience in web application development, portal integrations, and secure scheduling systems. I will ensure: * Clean, secure, and well-documented code * Seamless portal integration * Smooth appointment booking workflow * Clear communication * Revisions until you're satisfied I’d love to discuss your requirements and get started right away. Warm Regards, Monica Bhatia
₹37,550 INR in 2 days
5.4
5.4

Hi, I'm Karthik, a Senior Full-Stack Developer with 15+ years of experience building secure appointment scheduling systems, portal integrations, and workflow automation. I'm experienced in taking over partially completed projects, quickly understanding existing code, refactoring where needed, and delivering production-ready solutions. I can develop a secure login-based appointment scheduler with calendar management, slot validation, confirmation flow, and clean, well-documented code. I'll ensure the solution is modular, easy to deploy, and simple for your team to maintain and extend. My expertise includes Python, Django, Node.js, PHP, REST APIs, JavaScript, SQL, Git, CI/CD, and cloud deployment. I follow best coding practices and provide complete documentation along with deployment and handover support. I'd be happy to discuss your existing implementation, review the current progress, and propose a clear timeline and milestones. Best regards, Karthik
₹74,250 INR in 7 days
5.4
5.4

I HAVE A QUESTION: Have you already identified the specific U.S. web portal for integration? Knowing which one will help me assess the technical requirements and potential constraints more accurately. I understand your requirement for a production-ready appointment scheduler extension. With my experience building secure, scalable web applications (Node.js, PHP, SQL) and API integrations, I’m confident I can take over the existing work and deliver a polished solution. You specifically asked for verifiable experience with a similar system. One of my past projects was a secure scheduling portal for a US logistics company that allowed authenticated partners to book warehouse slots. The system supported: - Integration with their user directory for secure single sign-on. - A real-time calendar UI showing slot availability based on complex business rules. - A clean deployment script and documentation for hand-off to their internal admin. This experience directly mirrors your needs for authenticated user flows, calendar booking logic, and seamless integration. My ability to quickly comprehend and refactor an inherited codebase will be crucial here. I focus on building systems that are: - Scalable and production-ready - Secure and maintainable - Easy to extend and evolve Let’s connect and discuss the timeline. I'm ready to get started right away. Best regards, Philip O.
₹37,500 INR in 7 days
5.0
5.0

Greetings, I have read the project description I have been working on a similar project in recent time "Appointment Application " I am interested in the work open a chat to discuss requirements in details.
₹70,000 INR in 10 days
4.9
4.9

As an experienced full-stack developer with over 14 years in the industry, including a rich portfolio of 416 successful projects, I believe I have the skills, adaptability, and seamless project understanding you need for your USA Portal Appointment Scheduler project. I've built web applications with similar functionalities as required by your project in major U.S. portals, thus making me a perfect fit for this task. I invite you to take a look at my versatile tech stack which covers MERN/MEAN stacks, PHP (Core, Laravel, CodeIgniter), Python (Django), and Microsoft Tech like VB.NET and ASP.NET with C#. Furthermore, my collaborative approach means that I'm always ready to complement pre-existing partial work or refactor the codebase as required without compromising on quality or timeline. Finally, you can rest assured about the future administration of this project as my hand-off sessions provide detailed knowledge transfer for self-management of parameters; another feather in my cap that insists I'm the perfect match! Thank you for considering me for this opportunity.
₹75,000 INR in 25 days
5.1
5.1

Hi, I can take over your partially completed work and deliver a production-ready appointment booking extension integrated into your existing U.S. web portal. I have experience building secure, login-protected scheduling systems with role-based access, calendar-based slot selection, and rule-driven availability logic. I’m comfortable refactoring incomplete codebases quickly and stabilizing them for production use. What I will deliver Secure authentication flow (existing or new integration) Calendar-based slot booking UI Backend slot validation based on your business rules Real-time availability checks to prevent double booking Clean confirmation page with booking summary Admin-configurable slot rules for future updates Deployment script + environment setup guide Approach I will first review your current codebase to understand existing progress, fix architectural issues, and standardize the booking flow. Then I’ll integrate or rebuild only where necessary to ensure stability, performance, and maintainability. Experience Appointment booking systems with authentication Portal integrations and legacy code refactoring Production-grade scheduling tools with rule-based availability Delivery Clean, documented code Simple deployment process Final handover session for your admin team I can start immediately after reviewing your current implementation and define a clear milestone plan within the first 24 hours.
₹37,500 INR in 10 days
4.3
4.3

As a talented and innovative MERN Stack Developer, I have the skillset and experience you require to successfully complete your USA Portal Appointment Scheduler. I possess comprehensive understanding of web development technologies, including CSS, HTML and JavaScript which suits quite well for this task. Additionally, I have a keen eye for detail making me adept at quickly grasping inherited work and effectively refactoring it for optimal performance. My previous projects have involved building similar login-protected appointment tools, making me thoroughly understand the intricate needs of this kind of software. I am a master at creating custom solutions to suit individual needs and believe that your unique project deserves nothing less. I believe collaboration is essential in ensuring a flawlessly executed and innovative project and I guarantee to be collaborative in every singe step of the way. With my expertise and your clear vision, we can create a dynamic, user-friendly, reliable yet powerful extension that will enhance users' experience on your portal. Let's talk timeline and milestones to make it happen soon!
₹37,500 INR in 7 days
3.5
3.5

Your project requires more than a simple booking form — the critical part is making the scheduling flow reliable inside an authenticated portal environment while handling inherited code safely. I can take over the existing implementation, audit the current architecture, identify unstable areas, and deliver a production-ready extension with clean deployment and maintainable structure. The implementation would include: - Secure authenticated session handling - Calendar-based appointment flow - Slot validation based on your internal business rules - Conflict prevention and booking consistency checks - Confirmation and status tracking screens - Refactoring of unfinished or unstable modules - Deployment script and technical handoff documentation Given that this integrates into an existing U.S. portal, I would prioritize compatibility, low-friction deployment, and defensive error handling to avoid issues with session expiration, duplicate reservations, or inconsistent slot states. I have experience building protected scheduling and workflow systems integrated with external platforms and can share implementation details and technical samples relevant to this type of workflow during the discussion. Estimated delivery for a stable first production version is around 10–14 days depending on the current state of the inherited codebase and portal constraints.
₹72,914.77 INR in 14 days
3.7
3.7

Hello, I can develop a secure, production-ready appointment booking extension that integrates seamlessly with your existing U.S. portal. I'll quickly understand the existing codebase, complete the unfinished work, and deliver a clean, scalable solution with a smooth booking experience. **What I Will Deliver** ✔ Secure user authentication ✔ Appointment booking system ✔ Calendar & slot validation ✔ Portal integration & refactoring ✔ Clean, documented code ✔ Deployment & admin handover I will review the existing implementation, refactor where necessary, complete the booking workflow, validate appointments against your business rules, thoroughly test the extension, and ensure it is production-ready with an easy-to-manage setup. I look forward to discussing your project. **Best regards,** **Usama K**
₹38,250 INR in 2 days
3.4
3.4

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