REST APIs are the interface between clients and servers that allows for data to be shared across platforms, providing a seamless connection between applications, databases, and other resources. A REST API Developer is the programmer who helps clients connect their applications to a certain platform and ensure data is flowing between the two in an efficient, secure manner. This can help to reduce friction, improve performance & scalability, boost security, streamline website navigation, and more.

REST API Developers build and maintain custom programming to enable automated data retrieval and communication with a client’s desired application or platform. This can encompass services such as quickly integrating third-party payment systems into an existing website, minimizing manual work and improving customer experience. They may also incorporate priority systems; for example creating different APIs for handling bulk vs single requests for heavy workloads. Ultimately a REST API Developer helps clients bridge the gap between complex platforms and transform data into valuable business insights.

Here’s some projects that our expert REST API Developers made real:

  • Establishing communication between different applications
  • Creating priority systems for managing large volumes of requests
  • Integrating third-party payment systems into an existing website
  • Developing programming to seamlessly retrieve dynamic data
  • Designing secure connections to protect confidential information

Our highly-skilled REST API Developers are experts when it comes to stitching together the critical links which connect disparate platforms together. With years of experience they have been able to tackle innumerable projects which have led to successful outcomes for our clients. If you have an issue related to connecting your application with another platform or require automated data retrieval services then you can post your own project here on Freelancer.com and hire one of our experienced developers today!

From 68,516 reviews, clients rate our REST API Developers 4.9 out of 5 stars.
Hire REST API Developers

REST APIs are the interface between clients and servers that allows for data to be shared across platforms, providing a seamless connection between applications, databases, and other resources. A REST API Developer is the programmer who helps clients connect their applications to a certain platform and ensure data is flowing between the two in an efficient, secure manner. This can help to reduce friction, improve performance & scalability, boost security, streamline website navigation, and more.

REST API Developers build and maintain custom programming to enable automated data retrieval and communication with a client’s desired application or platform. This can encompass services such as quickly integrating third-party payment systems into an existing website, minimizing manual work and improving customer experience. They may also incorporate priority systems; for example creating different APIs for handling bulk vs single requests for heavy workloads. Ultimately a REST API Developer helps clients bridge the gap between complex platforms and transform data into valuable business insights.

Here’s some projects that our expert REST API Developers made real:

  • Establishing communication between different applications
  • Creating priority systems for managing large volumes of requests
  • Integrating third-party payment systems into an existing website
  • Developing programming to seamlessly retrieve dynamic data
  • Designing secure connections to protect confidential information

Our highly-skilled REST API Developers are experts when it comes to stitching together the critical links which connect disparate platforms together. With years of experience they have been able to tackle innumerable projects which have led to successful outcomes for our clients. If you have an issue related to connecting your application with another platform or require automated data retrieval services then you can post your own project here on Freelancer.com and hire one of our experienced developers today!

From 68,516 reviews, clients rate our REST API Developers 4.9 out of 5 stars.
Hire REST API Developers

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    I need a developer who can build a clean, reliable cPanel/WHM plugin that lets server owners route all outgoing mail through the TurboSMTP API. My servers run on Linux and I’d like to host the finished package so customers can download the installer, drop it into their own cPanel/WHM environment, enter their TurboSMTP credentials and start sending immediately. Core scope • Outgoing mail only: the first release just has to relay messages through TurboSMTP. I may revisit inbound handling later, so keep the code modular enough to add that without a rewrite. • Admin-only authentication inside WHM: the interface must respect existing WHM privilege levels—only root or reseller-level admins should be able to view or change the API key. • Seamless installation: an S...

    $17 / hr Average bid
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    138 bids

    Senior Full-Stack Developer — Production-Ready Data Intelligence Platform I am looking for an experienced senior full-stack/platform developer to take an existing data intelligence platform from its current development state to a secure, stable and production-ready product. This is not a greenfield build. A substantial application, architecture, database, frontend/backend and technical documentation already exist. The objective is to review what has been built against the intended architecture, identify gaps and technical debt, and complete the work required for production deployment. Platform Overview The platform is an enterprise data intelligence application that integrates data from customer business systems, processes and standardises it into a canonical data model, and prov...

    $776 Average bid
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    170 bids

    We’re looking for a Senior Full-Stack Developer to help us improve and complete Aroma, an existing luxury perfume e-commerce platform. Aroma already has a working React storefront and Express API, including a luxury-oriented landing experience, product catalog, filtering, product detail pages, shopping bag/cart functionality and basic user registration/login. The current implementation is a demo/reference version rather than a production e-commerce system. The goal is to build on the existing foundation and turn it into a complete, polished, production-ready e-commerce platform without unnecessarily rebuilding functionality that already works well. 1. Existing Application Review Start by reviewing the current application and customer flow to understand what is already working, wh...

    $1694 Average bid
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    346 bids

    I’m ready to move our educational institute onto a unified digital platform and need a full-stack Flutter developer who can deliver both sides of the product: • A cross-platform mobile app for Students, Parents and Teachers • A browser-based admin dashboard that keeps everything running smoothly Mobile app scope The core build must let users view real-time attendance tracking, check grades and upcoming assignments, and exchange messages with teachers. Each screen should adapt to the three in-app roles—Student, Parent and Teacher—so the right data and actions appear only where they belong. Admin dashboard scope On the web side, I’ll need straightforward user management (add, suspend, reset), flexible content management for notices or resources,...

    $543 Average bid
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    134 bids

    I need an AI-driven recommendation system that studies on-site user behavior and serves up relevant products and content in real time on my website. The core job is to design, train, and deploy a model that can interpret click-stream, dwell-time, and purchase history data, then return ranked suggestions through an easy-to-call API or directly inside the site’s codebase. Here is what success looks like to me: • A behavior-based algorithm (collaborative, content-based, or hybrid—you can advise on the best fit) developed in Python using libraries such as scikit-learn, TensorFlow, PyTorch, or a framework you prefer. • A lightweight service—REST or GraphQL—that exposes “getRecommendations(user_id)” so my front-end team can drop it straight into...

    $182 Average bid
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    42 bids

    I’m putting together a cross-platform mobile application that will run natively on both iOS and Android. To move the project forward I need a single developer (or a tightly-knit duo) who is equally comfortable building the UI in React Native and crafting a robust Java Spring Boot back end. The current project notes list “For Mobile Application Tech team” under required features; I’ll walk you through the product vision and we can refine the final feature set together during our first sprint-planning call. What I do know is that the app must feel fully native on each platform, share a single codebase wherever possible, and communicate with a secure, well-documented REST API you will also build. Key expectations • Set up the React Native project, implement sc...

    $170 Average bid
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    43 bids

    My SaaS is running on a “Lovable” stack and I already hold active accounts with both Paddle and Lemon Squeezy. What I need now is a clean, production-ready integration that: • Lets new and existing users choose a plan and pay through either provider • Creates and maintains their recurring subscriptions automatically • Syncs status changes (upgrade, downgrade, cancel, failed payment) back to my app in real time Please wire up the REST APIs, webhooks and any server-side logic so that revenue lands in my personal payout accounts exactly as Paddle and Lemon Squeezy allow. I will expose the current user, plan and license tables plus a staging environment as soon as we start. Acceptance will be simple: a test user can subscribe, renew, upgrade and cancel on bo...

    $232 Average bid
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    157 bids

    I need a clean, reliable approval workflow that plugs seamlessly into both our existing web application and the companion mobile app. The flow is strictly for internal staff: a team member submits new-customer details, a manager reviews the record, and a final approver signs off before the account is activated. The core logic must: • Capture and store each stage (Initial submission → Manager review → Final approval) with full audit history. • Trigger real-time email or in-app notifications so no step stalls. • Expose REST/GraphQL endpoints that our front-end teams can call from React (web) and Flutter (mobile). • Respect role-based access controls already in our PostgreSQL DB. Deliverables I expect: 1. Database schema updates and migration scri...

    $132 Average bid
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    50 bids

    I already have a working chatbot and chat system written in Python; now I want to transform it into a full-fledged customer-service agent. Its core jobs are clear: answer FAQs, process orders, and handle complaints or return requests. All of this must work seamlessly inside both my website and our upcoming mobile app. What I need from you • Review and refactor the existing Python codebase so it is clean, modular, and ready for production. • Strengthen the NLP logic so common customer questions are recognised reliably and routed to the right action. • Integrate order-processing and ticketing endpoints (they are REST/JSON) so the bot can create, update, and close orders or complaint cases. • Package the finished bot as an easily embeddable web widget plus a light...

    $31 / hr Average bid
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    117 bids

    I already have a working chatbot and chat system written in Python; now I want to transform it into a full-fledged customer-service agent. Its core jobs are clear: answer FAQs, process orders, and handle complaints or return requests. All of this must work seamlessly inside both my website and our upcoming mobile app. What I need from you • Review and refactor the existing Python codebase so it is clean, modular, and ready for production. • Strengthen the NLP logic so common customer questions are recognised reliably and routed to the right action. • Integrate order-processing and ticketing endpoints (they are REST/JSON) so the bot can create, update, and close orders or complaint cases. • Package the finished bot as an easily embeddable web widget plus a light...

    $244 Average bid
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    96 bids

    I want to build the first release of a social media mobile app that gets the user-profile experience absolutely right. This milestone is all about secure sign-up / login, a clean profile page (avatar, bio, basic stats) and a simple search so members can find one another. Messaging and content sharing are on the roadmap, so please structure the code so those pieces can drop in later, but they are not part of this delivery. I’m flexible on stack—Flutter, React Native, or fully native—as long as the finished product runs smoothly on both iOS and Android and the codebase is well-documented. A lightweight backend such as Firebase, Supabase, or a REST service is fine; choose whatever lets you move fastest while keeping things maintainable. Deliverables • Complete source ...

    $563 Average bid
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    68 bids

    SenderX Live Demo: SenderX is a complete SaaS-based SMS Gateway platform built with Laravel 12. It allows businesses to turn their own Android phone and SIM card into an SMS gateway and send SMS from their website, application, or any software through a simple REST API. Key Features: • Multi-user SaaS with subscription & plan management • Android device pairing via QR code • Multiple phones & multiple SIM support • REST API for sending and tracking SMS • Secure API keys for different applications • Bulk SMS & contact groups • Scheduled SMS with timezone support • Sent, delivered & failed message tracking • Real-time webhooks • Complete message history & searchable logs • Device monitoring — online/offline, ...

    $762 Average bid
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    157 bids

    Developer Requirements — Fan-to-Celebrity Gift Web App (Version 1) 1. Project Goal Build a fully functional, production-ready Web App, not a demo/prototype. The platform will allow fans to send/request physical gifts to celebrities, actors, influencers and creators while protecting their private addresses. Version 1 will use one central collection/processing station in Delhi, existing courier/postal services, and no own courier fleet. Android/iOS apps are not included in V1, but the architecture must support a future Android app using the same backend/API/database. 2. User Roles 1. Fan 2. Celebrity / Influencer / Creator 3. Admin Each role requires secure login, dashboard and role-based permissions. 3. Fan Features - Account creation and mandatory identity verification - Cele...

    $1124 Average bid
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    76 bids

    I’m kicking off the first phase of a brand-new real-estate rental platform and need an experienced full-stack engineer who enjoys shaping products from day one. Our immediate priority is the user onboarding and application flow: secure email-and-password registration, profile creation, document upload, and a smooth path for tenants to submit rental applications. Once that foundation is solid, we’ll expand into listings, search, and end-to-end rental management. You’ll be pairing React, , and TypeScript on the front end with a Node.js REST API on the back. I’m looking for someone who can help define the architecture, choose the right tooling, write production-ready code, and keep scalability in mind from the outset. If you have thoughts on introducing Web3 or bloc...

    $55 / hr Average bid
    $55 / hr Avg Bid
    243 bids

    I already have a working chatbot and chat system written in Python; now I want to transform it into a full-fledged customer-service agent. Its core jobs are clear: answer FAQs, process orders, and handle complaints or return requests. All of this must work seamlessly inside both my website and our upcoming mobile app. What I need from you • Review and refactor the existing Python codebase so it is clean, modular, and ready for production. • Strengthen the NLP logic so common customer questions are recognised reliably and routed to the right action. • Integrate order-processing and ticketing endpoints (they are REST/JSON) so the bot can create, update, and close orders or complaint cases. • Package the finished bot as an easily embeddable web widget plus a light...

    $258 Average bid
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    137 bids

    Our product team in Hyderabad is ready to onboard a fresh graduate who can take full-stack responsibility for completely new application development, combining Java + Spring Boot on the server side with React on the client side. Day-to-day you will design RESTful endpoints in Spring Boot, wire them to a clean React interface, write unit tests, and commit everything to Git with well-documented pull requests. Skills to bring: • Solid academic grounding in core Java concepts and object-oriented design • Hands-on familiarity with React. If you are a Hyderabad-based fresher excited about owning features end-to-end in a collaborative, small-team environment, I look forward to working together.

    $214 Average bid
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    26 bids

    I’m kicking off a new browser-based application and the very first milestone is rock-solid user authentication. I need a secure, scalable login and registration flow—think sign-up, email verification, password reset, and role-based access all wrapped in clean, well-documented code. You’re free to suggest the best stack for the job; I’m open to modern frameworks such as React, Vue, Angular or a classic server-rendered approach if it suits the project better. What matters most is that the authentication layer is bulletproof, follows current OWASP recommendations, and can plug into future modules without rewrites. Deliverables (initial phase) • Fully functional sign-up / login / logout workflow • Password recovery & email confirmation • Rol...

    $21 / hr Average bid
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    217 bids

    I have an online store that sells Murder Mystery 2 items and I already have the purchase interface and all the necessary API/backend. I now need to create the module that takes care of automatic delivery within Roblox, written in Luau, so that each customer receives the purchased item without manual intervention - total focus on improving the player's experience. Main scope • Listen to the "approved order" webhook of my API and capture Roblox user + item list. • Put the order in a queue and choose, among my mule accounts, the one that has the item in stock. • Invite the customer to the VIP server and detect his presence in-game. • Conduct the trade 100% according to the rules of Roblox/MM2, confirming that the right item has been delivered. • U...

    $708 Average bid
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    95 bids

    Python AI CRM Automation MVP — API Integration & AI Workflow I am building an AI-powered CRM automation system for a business and are looking for a strong Python developer to help develop the initial technical MVP. The system will connect a CRM/API with a Python backend and an AI layer to automate selected customer and lead-management workflows. This is intended to become a longer-term project, but we want to begin with a focused technical milestone before expanding the scope. The proper developer will help with: * Python backend development * CRM API integration * REST API development * Database design and queries * CRM data retrieval and updating * AI/LLM API integration * Structured data processing * Automation workflow implementation * Error handling and logging * Basic a...

    $21 / hr Average bid
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    229 bids

    Our team relies on Odoo’s Sales, Inventory, and Accounting apps, and we’ve reached the point where the out-of-the-box setup no longer fits our workflow. I need an Odoo specialist who can: • Custom-tailor each of the three modules so screens, fields, and logic align with the way we actually sell, stock, and book revenue. • Integrate Odoo with our existing third-party tools (CRM, courier API, and a small in-house finance dashboard) so data flows seamlessly. REST and XML-RPC experience will be handy here. • Walk the core users through the revised environment, recording short how-to sessions so new staff can self-train later. Key acceptance criteria • All customisations survive standard Odoo upgrades. • End-to-end order flow (quote → invoice)...

    $14 / hr Average bid
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    94 bids

    I already have VJ_DOC live on Vercel and open-sourced on GitHub, but I now want to take it from “nice demo” to a polished, production-ready product. My first priority is feature enhancement, with a strong eye on smooth user flow. You will be working in a TypeScript stack (React on the front end, Node.js + REST API on the back end) and are expected to follow modern development practices, clean architecture, and secure file handling throughout. Core enhancement goals • Advanced file annotation that feels as snappy as native apps • Seamless e-signature integration, including signature capture, placement, and audit trail • Cloud-storage connectivity so users can pull from and save to services like Google Drive or AWS S3 without leaving VJ_DOC In parallel, I...

    $132 Average bid
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    41 bids

    Our team relies on a fully custom-built CMS & CRM written in JavaScript/Node.js. It underpins everything from project and retainer tracking to sales pipelines, and it already talks to Gmail, Google Docs, and ChatGPT to automate daily workflows. I need a reliable technical partner who can step in whenever our in-house developer is unavailable, keep an eye on system health, and roll out small-to-mid-size enhancements we queue up. Think of it as light “on-call” coverage mixed with incremental feature work rather than a full-time rebuild. Core expectations • Proactively monitor the application, troubleshoot outages or performance drops, and deploy fixes with minimal downtime. • Ship new features or integrations on request—these could range from adding a ...

    $57 / hr Average bid
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    202 bids

    We are looking for an Adobe Journey Optimizer (AJO) Developer to design, build, test, and support customer journeys and personalized communications using Adobe Experience Platform and Adobe Journey Optimizer. Key Responsibilities Design and configure AJO journeys, campaigns, events, conditions, and audience based orchestration. Build and manage email, SMS, push, and other channel configurations within AJO. Develop reusable email templates, fragments, content blocks, and personalization rules. Configure and troubleshoot AEP schemas, datasets, identities, profiles, and audiences required for AJO use cases. Implement journey triggers using AEP events, APIs, streaming data, and batch audiences. Work with RTCDP/AEP teams to ensure audience qualification and profile data are availab...

    $230 / hr Average bid
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    6 bids

    We run Galadima, a progressive-web ERP we built on the MERN stack, and I’m looking for someone who can step in and own the entire engineering workflow. Your first mission is crystal clear: strengthen and expand our RESTful API layer so the platform talks flawlessly to the Freshworks ecosystem while exposing clean endpoints for our own modules. Immediate priority The APIs and integrations come first. I need robust, well-tested REST endpoints that connect: • User management • Inventory management • Financial records • Human Resources Management • Territory Management • Customer Relationship Management • Procurement Management Once the integration layer is solid, you’ll continue shaping the overall application architecture, ha...

    $443 Average bid
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    208 bids

    My retail business is ready to launch an end-to-end e-commerce presence built entirely with Flutter. I want a single code-base that delivers: • Native-quality mobile apps for Android and iOS • A web build that looks and performs perfectly on both desktop and mobile screens Core features I expect in the first release: • Secure user registration / social login • Hero banners, category grid and personalised product feed on the home screen • Catalog with search, filters and detailed product pages (images, variants, reviews) • Cart, wishlist and address book tied to the user profile • Checkout powered by Stripe, with real-time order confirmation • Order tracking and push notifications at each status change • Profile section wher...

    $1050 Average bid
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    157 bids

    I’m ready to turn my existing REST API into a polished React Native mobile application. The API is fully documented and the screen designs are complete; what I need now is a clean, TypeScript-based codebase that follows good component architecture and stays as close to pure React Native as possible. Core requirements • Authentication: wire the app to my API using Basic authentication and persist credentials securely. • Navigation & UI: a tabbed interface that presents a master list (pulled from the API) and corresponding detail views, matching the provided Figma files pixel-for-pixel. • Offline experience: cache the entire app’s data locally so users can browse previously fetched content without a connection, with automatic background sync on reconnect...

    $786 Average bid
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    246 bids

    We need a developer experienced with WooCommerce, PHP, REST APIs, and payment/shipping integrations to complete an existing online store integration. Scope includes: - Integrate Paquetexpress REST API with WooCommerce. - Real-time shipping quotation in checkout based on destination, package weight, and dimensions. - Support predefined package/box sizes and correct package selection logic. - Generate Paquetexpress shipment after successful payment. - Generate/retrieve ZPL shipping labels. - Integrate pickup/recollection scheduling. - Configure and test NetPay as the WooCommerce payment gateway. Handle API errors, retries, duplicate shipment prevention, and logging. Test first in Paquetexpress/NetPay sandbox before production. The store is already running on WooCommerce. Paquetexpress sand...

    $246 Average bid
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    297 bids
    Android IP Camera & IoT App
    3 days left
    Verified

    I need a single Android application that brings three abilities together: • show the live HD feed from my existing IP cameras, • let me start / stop recording that feed and push the resulting files straight to my server, and • allow me to toggle an IP-based IoT switch from inside the same interface. A simple email-password login gate is required before anyone can use any feature. Once authenticated the user lands on a dashboard where the camera stream appears immediately; from there a record button begins saving footage and silently transfers it to my server (I will give you the endpoint and credentials). A separate tab or overlay houses the IoT switch with instant on/off feedback. I am open to whichever libraries you prefer—ExoPlayer, VLC, ONVIF, RTSP, MQTT, HT...

    $286 Average bid
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    40 bids

    I need a brand-new web application built on SAP Business Technology Platform using the CAP Model. The solution will be delivered as a cloud service and must run smoothly inside the SAP BTP environment. Scope The project starts from a clean slate, so you will set up the CAP project structure, model the domain with CDS, and expose the required OData or REST services. A simple yet secure log-in flow is mandatory; the app must authenticate users against the BTP XSUAA service. Once inside, users should see intuitive pages that let them submit data through responsive forms and later review that information through clear, attractive visualisations (charts or tables rendered via SAPUI5/Fiori Elements or an equivalent modern JS charting library). Core deliverables • End-to-end CAP projec...

    $5 / hr Average bid
    $5 / hr Avg Bid
    23 bids
    React UI & QA Development
    3 days left
    Verified

    I’m rolling out the first customer-facing release of our U.S. start-up product and need a React specialist who treats testing and quality assurance as the heartbeat of every commit. Here’s the landscape Our REST APIs are live, wire-ready, and I have high-fidelity Figma screens waiting. Your code should translate those pixels into clean, reusable React components (hooks, context, TypeScript welcome) while keeping performance lean. Quality first Testing and quality assurance is the priority. I expect functional coverage across modern desktop and mobile browsers, with a mix of manual exploration and any automated suites you judge effective. Unit and component tests must guard critical business logic, and every sprint should close with a concise test plan plus a clear defect ...

    $36 / hr Average bid
    $36 / hr Avg Bid
    222 bids

    I need a Flutter developer to build a polished mobile application that lets users browse available time slots and book consultation appointments from their phones. The app must run smoothly on both iOS and Android and communicate with my existing REST-based backend for everything—user authentication, schedule retrieval, booking creation, rescheduling, and cancellations. Here’s what matters most: • Clean, maintainable Flutter code that compiles for iOS and Android without platform-specific hacks. • Solid REST API integration with proper error handling and token-based security. • A straightforward flow where a user logs in, views consultant availability, confirms a slot, and receives an in-app and push notification of the booking. • Responsive, modern...

    $33 / hr Average bid
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    291 bids

    I need a solid backend written in Python that powers one-on-one messaging for an existing mobile chat application. The core tasks are to expose clean REST and WebSocket endpoints, handle real-time delivery, persist messages reliably in PostgreSQL, and keep latency low under moderate load. Authentication is already in place; your job starts at the moment the client is authorised. From there the service must: • accept text, emoji, and small attachment payloads • write each message atomically to Postgres, marking it delivered and later read • push live updates back to the correct recipient through WebSockets • expose a simple status route for health checks and basic metrics Unit tests that cover the message flow, delivery confirmations, and failure scenarios ...

    $419 Average bid
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    117 bids

    # Mobile App Development – Personal Life Manager (Ionic/Angular Preferred) ## Project Description We are looking for an experienced **mobile app developer** to develop a modern **Personal Life Management mobile application** for Android and iOS. The app will help users keep track of important personal information, events, reminders, and goals in one place. ## User Features Users should be able to: * Register and securely log in * View their personal dashboard * View records assigned/created by Admin * View upcoming reminders and events * Manage/view their profile The main record categories will include: ### Vehicle / Bike Service * Vehicle details * Registration number * Last service date * Next service date * Service history * Service reminders ### Account Information * B...

    $223 Average bid
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    65 bids

    I'm looking for a testing specialist who can independently design and execute performance testing (load, stress, spike, and soak) against my web application and its authenticated REST APIs, and who's also comfortable testing my mobile app (iOS/Android) for stability and crashes using Crashlytics or Sentry data. The primary aim is to identify performance bottlenecks and crash-prone areas, so I need someone comfortable collecting hard data and translating it into clear, actionable recommendations. Once we start, I'll give you Swagger/OpenAPI docs or a Postman collection along with the required auth credentials, plus access to our Crashlytics/Sentry dashboards for the mobile app. You'll be expected to: • Plan realistic test scenarios that cover normal traffic, antic...

    $925 Average bid
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    61 bids

    We are looking for an experienced freelancer or software development team to build a DPDP Act (Digital Personal Data Protection Act) compliance solution. Requirement: Build a software/application for DPDP Act compliance Source code must be provided Complete ownership of the developed solution and source code User-friendly web-based application preferred Data privacy and security should be considered during development Admin dashboard and relevant compliance features Documentation and basic technical support required Important: We are open to either: Developing a new DPDP Act compliance software from scratch, or Customizing/providing an existing DPDP compliance solution, provided the complete source code and necessary rights are available. Freelancer should have: Experience in privacy/data ...

    $6272 Average bid
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    44 bids

    I need a seasoned MERN developer who can take a business idea and turn it into a fully working, production-ready web platform. This is far beyond a simple CRUD site—I’m aiming for an end-to-end system that automates internal workflows, stores and processes data efficiently, and delivers real-time dashboards my team can rely on every day. Here’s what the work looks like: • React will drive a responsive, component-based interface that feels fast on both desktop and mobile. • Node.js with (or a comparable framework you prefer) will power a secure REST or GraphQL API, built with clear layering and strong typing where appropriate. • MongoDB will serve as the primary data store; I need well-designed schemas, indexing strategies, and aggregation pipelines ...

    $237 Average bid
    $237 Avg Bid
    147 bids

    I have a fully documented REST API and finished Figma designs ready to go. What I need is a clean, future-proof React Native implementation that speaks to that API, authenticates users with simple email-and-password credentials, and then presents product listings in an infinite-scroll list. Tapping any item should push to a detail view that highlights user-generated product reviews first; the design may evolve to include description or pricing later, so keep the component structure flexible. Code quality matters as much as the UI. Please write everything in TypeScript, organise UI and business logic into reusable, well-named components, and avoid custom native modules unless we hit a hard limit with the JS APIs—maintainability is the priority. The app must also work gracefully offli...

    $497 Average bid
    $497 Avg Bid
    100 bids

    I have an automated trading system that now needs to plug directly into one or more prop-firm APIs so trades flow seamlessly from my strategy to the firm’s servers. Your task is to handle the full integration: authenticate, pull account parameters in real time, send orders programmatically, and return execution reports back to my app. I will provide: • API keys, endpoint documentation, and my current strategy codebase (Python). • A sandbox account for initial testing, followed by a live account for final verification. You will: • Build the connection layer, respecting each firm’s rate limits and security requirements. • Map my strategy’s order objects to the firm’s required payloads. • Deliver clean, well-commented code plus a short README...

    $69 Average bid
    $69 Avg Bid
    68 bids

    I’m ready to give my HR-tech platform a modern, responsive interface and need a front-end specialist to make it happen. The server side already handles user authentication, database management and a full REST/GraphQL API, so your focus will be the user experience—clean, fast and accessible on desktop and mobile. To help me choose quickly, share links to past work that best shows: • production-ready UIs you built yourself • how you integrated with authentication and dynamic data • performance or accessibility wins you’re proud of If you’re comfortable with React (hooks, Redux or Context), TypeScript and modern CSS, you’ll feel right at home. Vue or Angular expertise works too—as long as it stays modular and testable. Once we agr...

    $457 Average bid
    $457 Avg Bid
    215 bids

    My web platform is already live and humming; now I want the same experience packaged as native iOS and Android apps. The core features you will bring over include event discovery and multi-type ticketing (QR codes generated in-app), venue booking and management, and a full creator marketplace with enquiry and chat capability. Three role-based dashboards—organiser, venue owner and creator—must mirror the existing web functions while feeling truly mobile. I am comfortable with either React Native or Flutter, provided that Razorpay remains our payment gateway and Firebase continues to handle real-time data, notifications and analytics. You’ll receive Figma screens, brand assets, and detailed REST API documentation the moment we sign the NDA. Beyond the build itself, the s...

    $380 Average bid
    $380 Avg Bid
    95 bids

    We are seeking an experienced Backend Developer to implement new messaging, media, privacy, and VoIP signaling, Screen Sharing features into our existing WhatsApp-like communication platform. Tech Stack: Backend: Node.js, Fastify, PrismaORM, MySQL Real-time & Media: WebSockets, Mediasoup (Audio/Video calls) Note: You will only be responsible for the backend development (REST APIs, WebSocket events, database schema updates, background jobs, and Mediasoup signaling). Our mobile development team will handle all front-end/app integration. 1. Chat & Messaging Module** * **Message Reactions & Replies:** * Add API endpoints and WebSockets/Socket events for attaching reactions (emoji) to specific `message_id`s. * Support threaded replies by referencing `parent_message_id` in the me...

    $826 Average bid
    $826 Avg Bid
    212 bids

    This is a full-time, two-year contract to design, build, and maintain a production-grade MERN application from the ground up. The entire stack—front end, back end, and database—will sit with one developer, so deep, hands-on experience across each layer is essential. Stack and tooling The current plan leans on Node.js for server logic, for rendering and routing, and MongoDb for data persistence. Everything should be wired together with clean, testable JavaScript/TypeScript, Git-based workflows, and familiar DevOps practices (CI/CD, containerisation, cloud hosting of your choice). Daily responsibilities • Craft responsive, interactive UIs that feel native on web and mobile. • Implement rock-solid user authentication and role-based access. • Build REST/Gr...

    $1134 Average bid
    $1134 Avg Bid
    101 bids

    Senior Technical Auditor for I am looking for an experienced senior full-stack technical auditor to conduct an independent review of an existing bilingual Saudi offers and loyalty platform called Chance Plus. The platform is currently live and deployed in production. This is not a new development project and I am not requesting a rebuild. The initial task is strictly to review, test and report on the existing implementation before onboarding the first real store. Technology stack: TypeScript React and Vite Node.js and Express PostgreSQL Drizzle ORM and database migrations REST APIs and OpenAPI Progressive Web App (PWA) GitHub, pull requests and CI/CD DigitalOcean App Platform and Managed PostgreSQL Arabic and English interfaces, including RTL support Platform structure: Custo...

    $824 Average bid
    $824 Avg Bid
    238 bids

    I need a lightweight Android application that keeps my customers instantly informed about their purchase progress. The core task is to build a stable push-notification system that fires whenever an order moves to a new status in our back-end. Each notification must be clear, timely, and triggered exactly once per status change so users never miss an update or receive duplicates. My API team will expose a simple REST endpoint returning the current order state; you can poll it or use webhooks—whichever gives the most reliable result on Android. Feel free to integrate Firebase Cloud Messaging if it speeds things up; I just need the service to scale and to handle basic fail-over scenarios. At this stage I am not asking for full real-time map tracking or a user-login module, but I would...

    $47 / hr Average bid
    $47 / hr Avg Bid
    78 bids

    I need a complete web-based freelance job network built from the ground up. The core idea is similar to the big freelance marketplaces: clients post projects, freelancers create profiles, and both sides can connect and transact in a safe, intuitive environment. Scope • Full front-end and back-end development, responsive for desktop and mobile • Account management for both freelancers and clients, including profile creation, portfolio upload and basic analytics • Project posting with search and filter functions so users can quickly find relevant work or talent • Real-time or near-real-time messaging between parties to negotiate terms before a contract is created • Admin dashboard where I can moderate users, approve listings and pull platform metrics Te...

    $866 Average bid
    $866 Avg Bid
    260 bids

    I’m building a web application and need a seasoned Java full-stack developer to work alongside me from backend through to the React UI. The help I’m after is truly end-to-end: designing or extending Java REST APIs, wiring them into responsive React components, and keeping everything clean, tested, and well-documented. You’ll jump between backend logic (Java 17, Spring Boot, JPA/Hibernate, Maven) and the React frontend depending on the task at hand, always with an eye on performance, security, and code quality. Unit and integration tests, pull-request reviews, and occasional CI/CD tweaks in GitHub Actions and Docker are part of the routine. Acceptance criteria for anything we merge are straightforward: • All automated tests pass and new code meets the existing style...

    $177 Average bid
    $177 Avg Bid
    79 bids

    Budget $50-$350 Delivery window within max of 120 days (Takes 3 days of work or 20 senior hours) The client is the founder and sole developer of an in-progress software platform. They are looking for an experienced developer to help complete the final stage of the build. Platform completion We need an experienced developer to complete an A-to-Z platform that is approximately 85–95% developed. The remaining work is fewer than 10 tasks and is expected to take a senior developer less than 20 working hours; detailed tasks and acceptance criteria will be shared after an NDA and confidentiality agreement are in place. Engagement Note: This engagement is for an experienced developer to complete the remaining work on an existing platform. The remaining scope is fewer than 10 tasks and is...

    $369 Average bid
    $369 Avg Bid
    206 bids

    Project Description: Developed an end-to-end AI-powered medical intelligence platform for analyzing chest X-ray images and assisting with disease prediction. The system uses Deep Learning with DenseNet121 to classify X-ray images into five categories: Normal, Pneumonia, Atelectasis, Cardiomegaly, and Effusion. Integrated Grad-CAM Explainable AI (XAI) to generate visual heatmaps highlighting regions of the X-ray that contributed to the model's prediction. Built REST APIs using FastAPI for image upload, prediction, model information, and health monitoring. The platform also supports prediction history and is designed for integration with AI-assisted medical report generation using LLMs. Key Features 1. Medical Image Analysis – Processes chest X-ray images using deep learning. 2. ...

    $17 / hr Average bid
    $17 / hr Avg Bid
    22 bids

    I’m onboarding a senior Oracle EPM Solution Architect (18 + years) for a high-visibility programme that starts on-site in the Middle East for roughly four to five months before switching to offshore delivery. The contract is ready to begin immediately (ideally within the next 15 days), and a CA, ICWA or CMA qualification is non-negotiable. The work centres on defining and governing the overall EPM architecture, shaping scalable financial models and driving end-to-end implementations across FCCS/HFM and EPBCS. Expect deep hands-on time with ASO/BSO cubes, complex calc scripts, Groovy, PowerShell, Python and EPM Automate, plus REST API–driven data integrations that must remain rock-solid under GAAP and IFRS requirements. A solid grasp of ERP and General Ledger architecture, cost...

    $7826 Average bid
    $7826 Avg Bid
    8 bids

    We're building the new web version of our product and are looking for an experienced front end developer to lead and support the rollout. You'll work primarily in React and , building the interfaces our customers use every day. The frontend integrates with a SQL Server database via a C# API — you won't be modifying the API or database directly, but you'll need to understand relational data and work comfortably against existing APIs. WHAT YOU'LL DO - Build and maintain UI features in React / - Consume and integrate with an existing C# REST API - Translate designs and requirements into performant, accessible, responsive interfaces - Write clean, maintainable, well-tested code and participate in code review - Collaborate with the wider team (and any backend/AP...

    $57 / hr Average bid
    $57 / hr Avg Bid
    445 bids

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