Summary Senior Full-Stack Developer with experience in JavaScript, python, nodeJS, php.

 We are building a multi-tenant AI-powered marketing operating system for SMBs. 

This is NOT an autonomous AI agent project.

 The platform uses deterministic workflow orchestration enhanced with AI services for:

* content generation,
* approvals,
* publishing,
* engagement analysis,
* brand-style learning,
* multi-platform social posting, * social media campaign.

 We need a senior engineer who understands production SaaS architecture, workflow reliability, API integrations, queues/retries, and AI integrations.

 REQUIRED EXPERIENCE:

* Multi-tenant SaaS applications
* Queue/retry systems
* Webhook reliability
* Idempotency / duplicate prevention
* API integrations (multiple social media platforms)
* Structured AI outputs (JSON schema validation)
* Background jobs / async workflows
* Production-grade backend architecture

 YOU SHOULD UNDERSTAND

* deterministic workflow orchestration,
* retries/backoff,
* distributed locks,
* tenant isolation,
* workflow state management,
* structured AI pipelines,
* cost governance,
* approval workflows.

 DO NOT APPLY IF YOUR EXPERIENCE IS MOSTLY:

* autonomous AI agents,
* chatbot-only projects,
* prompt engineering only,
* no backend SaaS experience.

 Project Scope:

* starting with 50 concurrent clients
* AI-generated social content
* approval-gated publishing
* multi-platform posting
* adaptive brand memory
* analytics + engagement tracking * paid social media campaigns

 To apply, please provide:

 1. Relevant SaaS/backend projects
 2. Experience with OpenAI structured outputs
3. Your preferred architecture approach for scalable workflow systems

We’re seeking a full-stack developer to help build a SaaS MVP using TypeScript and Next.js. The platform will center around a PostgreSQL-backed system with user authentication, role-based access control, asset tracking, inspection logging, and photo upload functionality. This is a data-driven product, so experience designing clean, scalable database structures and building reliable backend workflows is important. As part of the initial phase, we plan to launch a beta using Airtable to validate workflows and refine the data model before transitioning to a fully custom build. Experience working with Airtable or integrating it into early-stage products is a strong plus. We’re looking for someone who has solid experience with TypeScript and Next.js, can move efficiently, and is comfortable working on an evolving product. The goal is to have a functional MVP completed within the next three months. This isn't a hard deadline, if our goal is ambitious let us know and we can discuss.

Note: We are a well-funded startup with a very high engineering bar, working alongside senior engineers with experience from leading AI labs. This is a smaller initial paid task, but we pay well for excellent work and there is potential for a much larger collaboration if the fit is strong. Your PRs will be reviewed by strong engineers, so we are looking for someone who takes ownership, thinks clearly, and cares about shipping clean, production-ready code. Please only apply if you can hold yourself to that standard. We are not looking for generic AI-generated output or low-effort execution. # Implement Probabilistic Attribution Between Marketing Website and Electron Desktop App We have a marketing website where users can click to download our Mac desktop app. The app is distributed as a standard Mac DMG and built with Electron. We use PostHog for product analytics, and we also run Google Ads. Users may eventually sign in inside the desktop app through ChatGPT/auth, but many users will first be anonymous. We want to implement a simple first version of attribution that helps us understand which website visitors / ad campaigns / download clicks later become desktop app users. ## Goal Build a lightweight probabilistic matching system that connects: 1. A user visiting the marketing website 2. The same user clicking “Download” for the Mac DMG 3. The desktop app being opened for the first time 4. The user later signing in, when applicable The goal is not perfect identity matching. The goal is good-enough attribution for our current low-volume flow, roughly around 100 download clicks per week. ## What needs to be figured out The developer should determine the best simple implementation for: - Capturing enough information on the marketing website when someone clicks the Mac download button - Capturing enough information from the Electron app on first open - Matching those two events probabilistically on the backend - Passing useful attribution information into PostHog events - Associating the attribution with the authenticated user once the user signs in - Testing that the full flow works end-to-end The likely matching signals are things like timestamp proximity, hashed IP, platform, timezone, language/locale, and other non-invasive browser/app context. The implementation should avoid overcomplicated or privacy-invasive fingerprinting. ## What we should do Implement a simple backend-backed attribution flow: - When someone clicks “Download for Mac” on the website, create a download-attribution record. - Capture campaign data such as UTMs, Google Ads click ID if present, landing page, referrer, and PostHog anonymous/browser ID where available. - When the Electron app first opens, create or retrieve a persistent app install ID. - Send a first-open event from the app to the backend. - Backend attempts to match that first app open to a recent download click. - Store the match with a confidence level such as high/medium/low/unmatched. - Send attribution metadata as properties on relevant PostHog events. - Once the user signs in, connect the app install and attribution record to the authenticated user ID. ## What we should not do in this version We do not want to overbuild this. Do not: - Generate a unique DMG per user - Modify the signed Mac app bundle - Inject tokens into the installer - Implement custom deep links yet - Build a full deterministic attribution system - Use probabilistic matching to permanently merge PostHog user identities - Send raw IP addresses to PostHog - Add invasive browser fingerprinting Probabilistic attribution should be treated as estimated attribution, not as guaranteed user identity. ## Expected deliverables The task is complete when: - The website download flow records download intent and campaign metadata. - The Electron app records first-open/install metadata. - The backend can probabilistically match app first opens to recent website download clicks. - PostHog receives app events with attribution properties when a match exists. - The system links the app install to the authenticated user after sign-in. - There is a way to inspect/debug attribution matches. - The implementation is tested locally or in staging with realistic flows: - normal download → immediate app open - delayed app open - no matching download - multiple download clicks from the same network - user signs in after opening the app ## Important constraint This is a first version. We prefer a simple and maintainable solution that gives us useful attribution data over a complex solution that tries to be perfectly accurate.

Summary I'm building Artcade, a patent-pending peer-judged creative skill-gaming platform where people compete in drawing, photo, and writing contests, in 31-player cohorts, for real-money prizes. The mission is simple: incentivize imagination. The whole experience is generally built with AI prototyping. React/TypeScript, every screen from game selection through voting, results, wallet, and compliance. It was built fast and AI-native, and it's production-ish quality. Now I need a founding-level frontend/mobile engineer to help us on the last mile: convert it to a React Native iOS app and get a real build into TestFlight. That's the one thing that matters first. If you've shipped real mobile apps, you obsess over how a touch interface feels, and you're comfortable blending AI dev tools with strong engineering fundamentals, this role is for you. What You'll Do - Convert our React/TypeScript prototype into a React Native iOS app and get it live on TestFlight (the #1 priority. It unblocks everything downstream) - Stand up and manage TestFlight builds through a paced, compliance-gated cadence (build → cert gate → adjust → continue) - Own the drawing canvas end-to-end — multi-tool, touch optimization, responsiveness, performance. It's our signature surface and it has to feel great - Build the core game and voting flows (cohort fill, submission, the gated 5×6 → 5 → 1 voting flow, results) plus wallet, profile, progression, and responsible-gaming screens - Bring a real point of view on animation, transitions, and game feel — not just ship tickets - Use AI dev tools (Claude Code, Codex, similar) to move fast, and help systematize what works - Collaborate directly on product direction — this is a founding seat, not a ticket queue Ideal Candidate Experience - React Native Engineer (5+ years) with shipped mobile apps. - Real apps live on TestFlight / the App Store — React Native and/or native iOS (Swift/SwiftUI), not web-with-a-responsive-layout. - Strong React / TypeScript experience helpful. - UX craft on interactive, canvas, or touch-heavy surfaces. Mobile Expertise - React Native (Expo / bare workflow) and the iOS build + TestFlight pipeline - Touch handling, gesture systems, and 60fps performance on device - Animation depth — Framer Motion, Reanimated, or SwiftUI animation Craft & Canvas - Canvas / graphics / drawing-tool experience (Canvas API, WebGL, custom rendering) - A portfolio piece that's interactive and feels good to use — show us something you made - An eye for game feel, transitions, and micro-interactions AI-Native Builder Profile (Must-Have Mindset) - You've recently vibe-coded and are comfortable with AI dev tools like Claude Code, Codex, Droid - You blend AI output with your own logic and refactors — fluent, not dependent - You think of AI as a collaborator that lets a small team ship like a big one - You love testing new workflows and systematizing what actually works Highly Valuable - Mobile game experience — especially drawing / creative tools / rich touch interaction - Skill gaming, iGaming, or real-money gaming background (Skillz, Big Run, PrizePicks, etc.) - Real-time UX (WebSocket waiting rooms, live game state) - Design-fluent enough to pair tightly with a brand designer Soft Skills & Mindset - Operates like a founder — autonomous, pragmatic, fast - Runs from a prototype and a POV, doesn't wait for pixel-perfect specs - Communicates clearly and async-friendly - Comfortable with a paced, gated start-stop rhythm (the cert cadence is part of the job) - Cares how things feel, not just whether they work What You'll Get - A founding frontend seat on a product that's already built and ready to ship - Direct collaboration with the CTO on architecture and the CEO on product - 1099 contract-to-hire to start, converting to a full-time early-employee seat with equity on mutual fit - Real ownership of the surface users touch most — the draw tool is yours - The chance to define how an entire creative-gaming product feels on mobile Our Mission - We're building creative skill gaming that rewards imagination with real prizes. - The product is built. The job is to make it real on mobile, and make it feel incredible. - If you've shipped mobile apps you're proud of, you sweat the details of touch and motion, and you want to own a signature surface from day one, you'll fit right in. Note - This is U.S.-based and work-authorized (1099 → W-2 path). Rate is $50-70/hr depending on experience, negotiable up for strong mobile-game or drawing-tool backgrounds. We'll start with a short paid sprint on the actual codebase to align on pace and quality, then scale from there. Looking forward to building together.

We are seeking a motivated and skilled Front-End Developer to join our apparel technology team. In this exciting role, you will play a key role in building and enhancing the next generation of operational tools that will be utilized across various departments within our organization. Your primary focus will be on creating intuitive web applications and interactive dashboards that deliver real-time insights into crucial aspects of our operations, including production performance, inventory movement, sales trends, and overall operational efficiency. As a Front-End Developer, you will collaborate closely with a diverse group of professionals, including data analysts, operations managers, product stakeholders, and back-end engineers. Your collaborative efforts will be essential in transforming complex business data into clear, concise, and actionable user experiences. You will be responsible for designing and implementing user interfaces that not only convey critical information effectively but also enhance user engagement and accessibility. This position is particularly well-suited for developers who are passionate about creating data-rich applications and who excel at building user-friendly interfaces. You will be challenged to solve complex problems related to information presentation and workflow optimization, all while employing best practices in front-end development. Additionally, you will have the opportunity to stay updated on emerging technologies and trends, allowing you to improve and innovate the applications you develop. Your contributions will have a significant impact on the organization, empowering teams to make informed decisions, improving workflow visibility, and ultimately increasing productivity in multiple areas of the business. This is a unique opportunity for a talented developer looking to make a meaningful difference in an innovative and fast-paced environment. The required skills and requirements for this position are listed below: - Strong proficiency in React, JavaScript, TypeScript, HTML5, and CSS3. - Experience developing data-driven web applications or dashboard interfaces. - Understanding of frontend architecture and reusable component design. - Experience consuming APIs and handling dynamic data within applications. - Familiarity with state management solutions such as Redux, Zustand, or similar tools. - Strong debugging and troubleshooting skills. - Experience working with Git and collaborative development environments. - Ability to communicate effectively with both technical and non-technical stakeholders. - Strong attention to detail and commitment to user experience quality.

We are seeking an innovative and user-focused Front-End Developer to play a pivotal role in the development of modern web applications designed to enhance collaboration, automate essential business processes, and streamline daily operations across the organization. Your expertise will be instrumental in crafting responsive, high-performance user interfaces that empower employees, customers, and business partners to interact seamlessly and efficiently with our digital platforms. As a Front-End Developer, your primary responsibility will be to design and implement feature-rich web applications that serve a variety of functions, including customer self-service portals, internal collaboration systems, workflow automation tools, document management platforms, approval processes, scheduling systems, and a range of business productivity solutions. To achieve this, you will focus on delivering intuitive user experiences that aim to reduce complexity, enhance accessibility, and promote user adoption across multiple business functions. Furthermore, this position is ideally suited for developers who possess a passion for creating polished and engaging user experiences while tackling complex workflow challenges through the use of modern front-end technologies. You will have the opportunity to stay on the cutting edge of industry trends, leveraging frameworks and tools that promote best practices in web development. Your contributions will not only enhance the functionality of our systems but also create a lasting impact on how our organization operates and interacts with its stakeholders. Required Skills and Qualifications: - Extensive experience with modern frontend frameworks such as React, Vue.js, Angular, or similar. - Proficiency in JavaScript (ES6+), TypeScript, HTML5, and CSS3. - Experience in building responsive and accessible web applications. - Strong understanding of REST APIs and asynchronous data handling. - Familiarity with Git and collaborative development workflows. - Knowledge of front-end build tools and package managers. - Strong skills in debugging, troubleshooting, and performance optimization. - Excellent communication, collaboration, and problem-solving abilities.

I need an experienced developer to migrate an existing Base44 (React + Vite) prototype to production-grade native mobile apps for both iOS (App Store) and Android (Google Play), with architecture built to scale. Scope of work: Export and thoroughly audit the Base44 codebase. Migrate frontend to production React Native (Expo strongly preferred) for iOS and Android. Migrate backend logic to a scalable solution (e.g. Supabase or equivalent). Implement and rigorously test permissions, privacy requirements, and store compliance for both platforms. Verify, harden, and optimize all API integrations. Battle-test features, edge cases, and performance across iOS and Android devices. Prepare full submission readiness for Apple App Store and Google Play. Provide architecture guidance for scaling to high user volumes. Must-haves: Multiple live React Native apps successfully published to both the Apple App Store and Google Play (provide links). Experience migrating from no-code/AI-generated or web codebases to cross-platform native. Strong backend experience with scalable solutions (Supabase, Firebase, Postgres, etc.). Deep expertise in mobile permissions, privacy compliance, and the full submission/review processes for both iOS and Android. Excellent code quality with TypeScript, modern React Native patterns, state management, and navigation. Portfolio + GitHub examples required. References from previous production mobile projects a big plus. Strong communication for phased collaboration with clear milestones. Engagement: Phased project (Audit & Plan → Migration → Polish & Testing → Launch Prep). Available ASAP. Remote OK with preference for EST/overlapping hours. Florida-based a plus but not required. To apply: Email/DM [your email] with: App Store and Google Play links + relevant GitHub/portfolio Brief summary of relevant migration or scaling experience High-level proposed approach Availability ASAP

Job Description Project Overview We have a fully code-complete Micro-SaaS platform called BounceBack SMS. The app is an automated missed-call text-back and lead recovery system built using Next.js 15, Tailwind CSS, Twilio API, and Supabase. The repository is isolated, structured, and securely hosted in a private GitHub repository. We are looking for an experienced Full-Stack/DevOps Engineer to handle the production deployment, configure live API pipelines, manage database environment mapping, and ensure the entire setup runs on a frictionless, automated continuous integration/continuous deployment (CI/CD) framework. Scope of Work (Key Deliverables) 1. Infrastructure Mapping & Production Deployment Deploy the Next.js 15 frontend/backend application from our private GitHub repository to production hosting (Vercel/Render). Map and connect production environment variables, database schemas, and connection strings to our live database instance (Supabase/PostgreSQL). Configure a permanent automated CI/CD pipeline (e.g., GitHub Actions or Vercel integration) ensuring any future push to the ⁠main⁠ branch automatically rebuilds and deploys the app flawlessly. 2. Twilio API & A2P 10DLC Compliance Configuration Connect and secure our live Twilio API gateways within the backend architecture. Audit and verify that our messaging endpoints cleanly support incoming webhooks for missed-call detection. Crucial Milestone: Assist and audit our US A2P 10DLC Campaign Registration via Twilio to ensure 100% carrier delivery compliance (Privacy Policy and Terms pages are already live and coded in the repo). 3. Live Stripe Billing Integration Transition our checkout environment variables from Stripe Sandbox/Test Mode into Live Production Mode. Wire up our exact pricing architecture: $0 Setup Fee, 100 Free Leads Usage Trial, transitioning into a flat $19.99/Month Recurring Subscription. Ensure Stripe webhooks are completely listening to successfully provision, pause, or update customer account access tiers inside our database based on subscription state. 4. Handover & Bulletproof Documentation Provide a brief, plaintext ⁠.txt⁠ or ⁠.md⁠ technical handover file outlining the deployed environment structure, a list of active API webhooks, and step-by-step instructions for simple environment variable updates. Required Tech Stack Expertise Frameworks: Next.js 15 (App Router), React, Tailwind CSS Database: Supabase / PostgreSQL (Schema sync, migrations, security policies) APIs: Twilio SMS Gateway (Webhook architecture, A2P 10DLC registration compliance) Payment Rail: Stripe Billing API (Usage-based trials, recurring webhooks) DevOps/Version Control: Git, Private GitHub Repositories, Vercel/Render, CI/CD automation Preferred Qualifications Proven track record deploying independent Micro-SaaS or automation applications. Deep familiarity with strict US telecom carrier A2P SMS delivery guidelines to prevent messaging blocking or spam flags. Obsession with clean environment variable separation—absolutely no hardcoded credentials. Excellent technical communication skills and availability to run live end-to-end integration testing before final milestone sign-off. 🎯 Candidate Screening Questions (Include on Upwork) 1. Briefly describe your experience configuring Twilio webhooks and handling the US A2P 10DLC registration process to ensure high carrier delivery rates. 2. How would you configure Stripe to trigger a recurring $19.99/mo flat-rate subscription specifically after a user consumes exactly 100 free database actions/leads? 3. Confirm that you are comfortable working out of a private GitHub repository and setting up an automated CI/CD pipeline so I never have to manually pay for developer redeployments.

We're a fast-moving company with a strong in-house backend team looking to add a dedicated frontend developer on a retainer basis. This is not a one-off gig, we need someone available, responsive, and able to execute quickly when projects move. We're expanding our dev capacity and want to bring on someone who is hands-on, communicative, and fully present on every project they take on. Direct collaboration with our internal team is essential, we move fast and need someone who moves with us. WHAT YOU'LL BE DOING: Working directly alongside our in-house backend developers, design team, and marketing team to build and maintain web interfaces, implement designs, and ship features quickly. You'll own the frontend layer completely. WHAT WE NEED YOU TO KNOW COLD: - Tailwind CSS — this is non-negotiable, it's our primary styling approach - React and TypeScript — you should be writing this daily - Laravel — familiarity required, it's a core part of our backend stack - Astro — familiarity expected, you'll encounter it in our stack - Clean, responsive UI implementation with an eye for detail WHAT WE'RE LOOKING FOR: - Someone who writes their own code and takes full ownership of their work - Strong availability during US business hours - Fast turnaround without cutting corners - Clear, proactive communication throughout every project TO APPLY, PLEASE INCLUDE: - Your portfolio or GitHub link - 2–3 examples of projects built with Tailwind + React - A short note on your availability and how you handle tight deadlines

We are looking for a U.S.-based senior React/Firebase technical lead or software architect to help review and guide an existing SaaS product to pilot launch. The product is already built and deployed in staging. This is not a greenfield build. We need an experienced technical partner who can inspect the current architecture, review contractor work, identify launch risks, and help sequence the remaining work before pilot. Current stack: * React / TypeScript * Firebase Auth * Firestore * Firebase Storage * Firebase Cloud Functions * Firebase Hosting / GCP * GitHub The app is a multi-tenant SaaS platform with organizations, locations, employees, role-based permissions, training modules, SOPs, communications, request-off workflows, handbook acknowledgements, and admin consoles. We need help with: * Reviewing the existing React/Firebase architecture * Reviewing Firestore rules, Storage rules, Cloud Functions, auth/custom claims, and tenant isolation * Reviewing PRs and contractor work * Advising on remaining pilot-readiness work * Helping sequence frontend cleanup, UX/UI polish, admin console structure, and final security review * Identifying risks before real pilot customers are onboarded Important experience: * React + TypeScript SaaS applications * Firebase Auth / Firestore / Cloud Functions * Multi-tenant architecture * Role-based access control * Security-minded code review * GitHub branch / PR workflow * Ability to explain technical tradeoffs clearly We would like to start with a small paid technical review first. If it is a good fit, this may turn into an ongoing technical lead/advisor role. We are not looking for someone to blindly rebuild the app. We need senior judgment, architecture review, launch-risk identification, and practical guidance.