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I run a small business and I'm tired of tracking my stock in a messy spreadsheet that gets out of sync every week. I need a simple web app where I (and maybe one staff member) can log in and manage my inventory — add items, update quantities, mark things as low stock, and see everything in one clean list. Nothing fancy, just something reliable that replaces the spreadsheet.

Scope of Work:

Build a login page (email/password) so only authorized users can access the dashboard
Create an inventory list view showing item name, quantity, category, and price
Add/edit/delete inventory items through a simple form
Add a "low stock" flag/highlight when quantity drops below a number I set per item
Basic search/filter by item name or category
Clean, responsive layout that works on both desktop and mobile browser
Required Skills:

React
Node.js / Express
MongoDB
REST API design
JWT authentication
Tailwind CSS
Deliverables:

Fully working web app (frontend + backend) with source code delivered
Basic setup/run instructions (README) so I can host it myself or hand it to my IT person
One round of revisions after initial delivery
Client Requirements:

I'll provide my logo and brand colors (optional, plain styling is fine if not)
I'll confirm the exact inventory fields I need before you start (name, SKU, quantity, category, price, low-stock threshold)
I'll test the app within 2 days of delivery and report any issues

Estimated Timeline:
3-4 days from project start

Acceptance Criteria:
Project is complete when I can log in, add/edit/delete inventory items, see low-stock items highlighted automatically, search my inventory list, and the app works correctly on both desktop and mobile browsers — with no console errors and all core actions (login, CRUD, search) functioning as described above.

Optional Future Work (not included in this $100 scope):

Deploying the app live on a hosting platform (Vercel/Render) with a custom domain
Adding sales/order tracking on top of the inventory system

We're looking for an experienced Full-Stack Developer to help build a custom architecture for recruitment management platform from the ground up.

The platform will be used to manage candidates, job openings, recruitment pipelines, evaluations, communication, and internal recruitment analytics in one centralized system.

Core platform functionality:

- Candidate database with profiles, contact information, skills, professional experience, CVs and uploaded documents
- Candidate search and filtering based on skills, experience, location, and recruitment status
- Job creation and management
- Recruitment pipeline with customizable stages such as Applied, Screening, Interview, Technical Assessment, Final Review, Offer, Hired, and Rejected
- Candidate scoring and internal evaluations
- Internal notes and communication history
- Recruitment dashboards and analytics
- Role-based access for Admins, Recruiters, and Hiring Managers
- Authentication and user management
- Responsive web interface

Future development will include:

- Recruitment automation
- AI-powered candidate matching and scoring
- Automated notifications and reminders
- AI-generated candidate summaries
- Third-party integrations and additional reporting

Technical direction:

- React / Next.js for the frontend
- JavaScript / TypeScript
- Node.js / ExpressJS for the backend
- MongoDB for the database
- Redux where appropriate for application state management
- REST APIs and third-party integrations
- Responsive Design using modern HTML5 and CSS
- Git for version control

We're looking for someone who can take ownership of features and make sensible technical decisions without needing every detail specified in advance. Experience building SaaS platforms, dashboards, CRM systems, recruitment software, or other complex web applications is a strong plus.

We already have the product requirements and initial platform structure defined. The goal is to build a clean, scalable foundation that can continue to grow as the platform develops.

Who we want to hear from:

- Strong experience with React and JavaScript
- Solid Node.js backend experience
- Production experience with TypeScript
- Experience building complex web applications and dashboards
- Good understanding of API and database architecture
- Comfortable working with MongoDB and ExpressJS
- Experience with Next.js is a plus
- Strong understanding of responsive web development
- Able to work independently and communicate clearly
- Comfortable improving the architecture and product when better solutions are identified

We are seeking a full stack developer with Node.js, NestJS, React and PostgreSQL expertise to help us complete the last feature of our veterinary management platform

Responsibilities
- Build the pet's card management feature using a consistent integration approach
- Develop features end to end, including database changes, backend APIs, and frontend functionality

Requirements

- 5+ years full-stack, most of it on Node and TypeScript
- Strong PostgreSQL, including schema design, indexing and query optimisation
- Multi-tenant SaaS with real data isolation
- Comfortable inheriting a codebase and improving it rather than proposing a rewrite
- Third-party API integration experience, including retries and idempotency
- LLM API integration in production
- Subscription billing and payment reconciliation
- AWS in production
- Clear written and spoken English

Tech Stack (required)

Frontend: React, Next.js, TypeScript, Tailwind
Backend: Node.js, NestJS, TypeScript, REST, SocketIO
Database: PostgreSQL with TypeORM, Redis for cache and queues
Cloud: AWS with Lambda, S3, CloudFront, Cognito, SES
AI: OpenAI API
Tooling: GitHub with PR review, GitHub Actions, Sentry

Nice to have

- Experience with veterinary and healthcare domain
- Experience with insurance or third-party system integrations
- Experience handling sensitive documents and medical data securely
- Regular use of AI coding tools, with a strong habit of reviewing and validating generated code

To apply
Send your availability and answer the questions below.

We are looking for a full-stack engineer to help build secure credit card platform end-to-end, from the database schema to the user interface. You will join a small engineering team, own significant parts of the product, and help set the technical direction as the company grows. This is a hands-on role with a wide scope. You should be comfortable working independently, communicating clearly, and delivering high-quality work on time. Experience with similar financial or platform projects is a plus.

We’re looking for a Node.js developer to help us with some quick fixes and improvements on our existing web application.

The backend is built with Node.js, Express.js, PostgreSQL, and Redis. We currently have a few issues with API responses, payment webhook handling, and some backend logic that needs to be cleaned up.

We’re looking for someone who is comfortable working with an existing codebase and can quickly identify and fix issues without affecting the current functionality.

The work includes fixing several REST API endpoints, improving error handling, resolving a payment webhook issue, and making a few small PostgreSQL query improvements.

Experience with Node.js, JavaScript/TypeScript, Express.js, REST APIs, PostgreSQL, Redis, and third-party API integrations is important.

If everything goes well, we may also need help with additional backend functionality in the future.

We’re looking for an experienced MERN Stack Developer to build and maintain scalable web applications, SaaS platforms, dashboards, and custom solutions.

Requirements:

- Strong experience with MongoDB, Express.js, React.js, and Node.js
- REST API and third-party integrations
- JavaScript/TypeScript, Git/GitHub
- Responsive UI development
- Database optimization and debugging
- Experience with cloud deployment is a plus

Looking for ai and sales lead generator in this usa.

Advanced Nuclear Advisors Canada Ltd. (ANAC) is seeking a highly motivated person to help develop an AI powered Nuclear Market Intelligence Platform. The platform will combine United States Department of Energy (DOE) opportunities in the nuclear energy industry, nuclear industry market intelligence, regulatory developments, utility procurement activity, and advanced AI search capabilities into a subscription-based Software as a Service (SaaS) product.

The person will work directly with senior nuclear industry experts and help create a first-of-kind intelligence platform serving utilities, reactor developers, suppliers, investors, and government stakeholders.

Responsibilities
• Design and develop web application components
• Build automated data collection pipelines
• Integrate DOE, US Nuclear Regulatory Commission (NRC), US Federal Register, utility and market data sources
• Create AI driven search and summarization capabilities
• Develop opportunity tracking dashboards
• Build user authentication and subscription features
• Design knowledge graph and entity relationship models
• Implement natural language querying tools
• Develop automated email alerts and intelligence briefings
• Create APIs supporting future product expansion
• Support deployment to cloud infrastructure

Skills Required
• Python
• SQL
• React
• JavaScript or TypeScript
• API development
• Data scraping and ETL
• Artificial intelligence and large language models
• Git and version control

Preferred Qualifications
• Experience with FastAPI
• PostgreSQL
• Vector databases
• RAG architectures
• Cloud computing
• Interest in energy or nuclear technology

Ideal Candidate
• 3rd or 4th year Computer Science student
• Has built at least 1 AI SaaS product
• Comfortable with Python and React
• Uses ChatGPT, Claude, Cursor, and GitHub Copilot daily
• Has deployed applications to the cloud
• Understands modern AI architecture
• Interested in energy, infrastructure, or public policy

Success Metrics
By completion of the work term the student will have delivered:
• Automated nuclear intelligence gathering engine
• DOE opportunity tracking system
• AI assisted search capability
• User dashboard
• Opportunity alerting system
• Minimum viable SaaS platform ready for pilot customers

Stretch Objectives
• Develop a nuclear industry knowledge graph
• Build AI proposal generation tools
• Create predictive market intelligence models
• Deploy beta version with external user testing

We have an existing application that has accumulated a lot of technical debt. We need the right engineering team to help us upgrade the codebase and deliver features.

We are looking for an experienced engineering team (or a strong technical lead with their own developers) to take full ownership of the technical side. We want a clean, scalable architecture from day one. We don't want to hire 5 random freelancers and manage them ourselves. We need a cohesive team that knows how to build a complex product fast, but without writing messy code.

What You Will Do:
Review the existing project architecture (frontend and backend) the right way.
Develop a migration strategy
Set up basic CI/CD and deployment pipeline, static code analysis, AI skills/agents.
Work closely with us to estimate tasks and deliver features in sprints.

Tech Stack:
Frontend: React (Next.js), TypeScript
Backend: Node.js (Express or NestJS)
Database: PostgreSQL

We need senior-level engineers. We don't want juniors learning on our project.
You should have established workflows. If you use internal templates, component libraries, or AI tools to speed up boilerplate coding and save us hours, that is a huge plus.
Clear communication in English and the ability to explain technical choices in plain words.

Full Stack work

Full Stack work

Full Stack work

We are looking for an experienced AWS Solutions / Cloud Architect to provide 1-on-1 consultation and guidance on designing and setting up a modular microservices architecture on AWS.

Scope of Consultation & Guidance:

Review core project requirements and recommend optimal AWS services for microservices (e.g., ECS/EKS, Lambda, App Runner, API Gateway).

Advise on service decomposition, modular design patterns, and cross-service communication (REST, gRPC, Event-driven with EventBridge/SQS/SNS).

Guidance on foundational infrastructure setups, including CI/CD pipelines, container registries (ECR), IAM roles, and VPC configuration.

Best practices for service discovery, centralized logging (CloudWatch/OpenSearch), and distributed tracing (AWS X-Ray).

Deliverables:

Live consultation session(s) covering architectural design and step-by-step guidance.

High-level architectural roadmap or summary notes outlining recommended tools, patterns, and security best practices.

Requirements:

Proven experience architecting and deploying containerized or serverless microservices on AWS.

Strong familiarity with Docker, infrastructure as code (Terraform, CloudFormation, or AWS CDK), and DevOps best practices.

Excellent communication skills for guiding technical strategy.

We’re seeking a full stack developer to build and maintain web applications from concept to delivery. You’ll work on front-end and back-end development, support responsive design, and help improve application performance and reliability. The ideal freelancer can collaborate with our team, communicate clearly, and deliver clean, scalable solutions. Experience with modern web development workflows and a strong understanding of application architecture are important. This is a long-term opportunity for someone who can contribute consistently and help shape the product over time.

We are developing an AI powered communication and workfroce development skills platfrom for people in Jordan. We have built an MVP in Replit and now ready to deploy to validate and test with our university students in October.

We need a focused MVP centered around the core learner experience and learning loop, from onboarding and assessment through personalized learning, real-world communication tasks, AI coaching, retry, and progress.

About us:

We are ClearCore, a SaaS platform built for licensed cannabis dispensaries. Our software gives dispensaries a full point of sale system, order management, inventory tracking, staff management, compliance tools, and a member loyalty program, all in one place. We are a startup approaching launch and building our team as we go.

About the role:

We are looking for someone to join our team long term as a QA tester who can grow into full stack and DevOps work. Experience with cannabis compliance or METRC is a big plus and will stand out, but not required to apply.

Quick note on METRC for anyone new to the industry: METRC stands for Marijuana Enforcement Tracking Reporting Compliance. It is the seed to sale tracking system that most states require licensed cannabis businesses to use. It tracks cannabis products from the moment they are grown all the way through to the final sale, so the state can confirm everything is accounted for and compliant. You can learn more at metrc.com. Our platform integrates with METRC, and that integration is part of what you would eventually help us build and improve.

What this role looks like starting out:

You will spend your first couple weeks learning our product by testing it. Our platform has three dashboards, Admin, Shops, and Members. Your job is to click through each one daily, find bugs, and log them into our shared Notion doc. We review what you find and make code changes daily on our time zone so we can move fast together.

This role should only take a couple hours a day to start, Monday through Friday. No expectation of weekend work. We want you to actually learn how the product should work before moving into anything technical.

Once you know the front end well, you will get access to our GitHub. From there you can start reading the codebase and helping us improve the backend, including our METRC integration and other APIs.

If you also have front end UI skills, there is room to help improve the UI across all three dashboards and our two marketing websites as well.

Pay structure:

Starting rate is $5 per hour, paid semi monthly on the 15th and the last day of the month, which is the 30th or 31st depending on the month. This is a long term role from the start, not a short term project. As you grow with us and take on more, especially backend and METRC work, pay will increase based on your contribution.

What we are looking for:

Someone reliable who shows up daily Monday through Friday and communicates clearly
Comfortable testing software and writing clear bug reports
Willing to learn cannabis industry compliance and METRC over time
Interested in a long term role, we hire with the intent of growing together
Some background in QA, full stack development, or DevOps is helpful but we care more about attitude and consistency
Front end UI skills are a bonus

We want someone who is willing to learn this industry and grow with us through launch and beyond.

If this sounds like you, apply and tell us a little about your experience with software testing, full stack or DevOps work, and whether you have any exposure to cannabis or METRC.

We are looking for an experienced Full Stack Developer with strong expertise in React.js and Node.js to help us build, improve, and maintain a modern web application.

The ideal candidate should be comfortable working on both the frontend and backend, developing clean and scalable code, integrating APIs, working with databases, and troubleshooting existing functionality.

Responsibilities
Develop responsive and user-friendly web interfaces using React.js
Build and maintain backend services and REST APIs using Node.js
Work with databases such as MongoDB, PostgreSQL, or MySQL
Integrate third-party APIs and services
Implement authentication, authorization, and security best practices
Debug, optimize, and improve existing applications
Write clean, reusable, and well-structured code
Collaborate with our team to understand requirements and deliver features on time
Test applications and fix bugs across frontend and backend
Ensure applications are scalable, reliable, and optimized for performance
Required Skills
Strong experience with React.js
Strong experience with Node.js and Express.js
JavaScript / TypeScript
REST API development and integration
Database experience with MongoDB, PostgreSQL, or MySQL
Git and GitHub
Responsive web development
Understanding of authentication and API security
Good problem-solving and communication skills
Nice to Have
TypeScript
Next.js
AWS or other cloud platforms
Docker
CI/CD
Redis
Experience with SaaS or dashboard applications
What We’re Looking For
We are looking for someone who is reliable, proactive, detail-oriented, and capable of working independently. Experience working on production-level applications is a strong plus.

If you are interested, please share:

A brief introduction about yourself
Your experience with React.js and Node.js
Examples of similar projects you have worked on
Your GitHub or portfolio, if available
Your availability and expected hourly rate
We are open to the right developer for both short-term and long-term work.

We need a developer to build a government job portal website for a government organization. The project includes creating a user-friendly platform for job seekers, employers, and administrators, with features such as job posting, application management, and user account handling. The website should be secure, scalable, and easy to maintain. Experience with similar portal projects is preferred. Please share relevant examples of past work and your approach to delivering a reliable, production-ready solution.

I run an online pharmacy and prescribing service here in the UK, regulated by the GPhC, and I've had a platform built for it over the past year or so. It works - patients go through an eligibility check, a prescriber reviews and approves, payments run through Stripe and GoCardless. What it isn't is properly ready to go live. Rather than guess at what was left to do, I paid to have the codebase reviewed independently, task by task.

This job is the first chunk off that list: security hardening, getting the build clean, and setting up CI. Somewhere between 8 and 12 days of work, fixed price.

I'll be straight about why it's carved up this way. I don't know you, you don't know me, and there's a lot more work sitting behind this piece. I'd rather we did something small and well-defined first and saw how it went.

What you'd be working on

pnpm monorepo, TypeScript top to bottom. Express 5 with Drizzle and Postgres on the server, React 19 and Vite on the front. Stripe for cards, GoCardless for direct debits, both webhooks signature-verified.

There's already a fair bit in place: Helmet with a proper CSP, rate limiting on the auth routes, JWT sessions in httpOnly cookies with server-side revocation, TOTP MFA that's actually enforced, bcrypt, account lockout, an append-only audit log. I mention all that because "security hardening" in a job ad usually means the thing is a disaster. This one isn't. It's a decent build that needs finishing.

The tasks

1. Get the repo typechecking clean. There are 13 pre-existing errors - they've been counted, and they come down to a handful of causes.

2. Set up CI. Typecheck, lint, tests and a dependency audit on every PR, and block the merge if it's red. There's nothing there at the moment.

3. CSRF protection on the cookie-authenticated routes that change state. While you're in there, the non-production CORS config is far too permissive and there's no explicit body size limit.

4. Rate limiting needs extending to the rest of the endpoints that change state or can be enumerated. Keyed per-account as well as per-IP, and configured properly to sit behind a proxy - that last bit gets missed a lot.

5. Two dependency advisories to patch, and our vulnerability-management doc needs updating to match.

6. Two access-control fixes, plus one route that shouldn't be publicly reachable. Each with a test. One thing I'll say plainly here: this part is already scoped. All 81 endpoints were swept and we know exactly which ones are affected, so please don't price in time to go hunting for more. You'll get the detail once we're talking under NDA.

7. There's a form on the front end that tells people their message has been sent when it hasn't. That needs sorting.

8. A dev-only guard that keys off an environment variable in a way that fails open. Flip it so it fails closed, and put a check in CI so it stays that way.

Who I'm after

Someone senior who's done this on a real Express app in production. If you know why SameSite=Lax doesn't buy you CSRF protection, and you've written tests against the authorization paths rather than just the happy path, you're the sort of person I want. Health or finance background is a bonus but not essential.

UK or European hours would suit best. And because this is patient data, I'm going to ask where your team sits and whether anyone outside the UK/EEA would be able to see it. Not to catch anyone out - it's just something I have to be able to answer for.

How I work

Everything through the repo, short branches, PRs. Nothing turns up as a zip file at the end.

Fixes come with a test that fails without them.

When you tell me something's fixed I'll want to see it. For an access control that means showing me the request getting rejected, not the one that works. I'll send you a one-page note on what counts as evidence before you start, so we're not arguing about it later.

No real patient data in dev or test, synthetic only. There's a DPA to sign before you get repo access.

IP in the code, the infrastructure and the docs comes to the company on payment. Nothing copyleft without asking me first.

Named people only, MFA on everything, access switched off and secrets rotated when we're done.

If you spot something I don't know about - a data exposure, an access-control hole - tell me. I'd genuinely rather hear it.

Next steps

Please answer the screening questions. I'll read those before I read the cover letter. If you're shortlisted I'll send the full spec for this workstream under NDA - real file paths, acceptance criteria per task, and the day estimate I'm working to. I'd like to see your estimate next to mine before I award anything. If yours is a long way off in either direction that's worth a conversation, it doesn't rule you out.

Ready to start as soon as I find the right person.

We need an AI engineer to support our team with bug fixes and feature improvements for an existing project. The role involves identifying and resolving issues, improving system performance, and enhancing features to improve overall functionality. You should be comfortable working in a collaborative environment and able to contribute to both short-term fixes and longer-term improvements. Experience with AI-related development and software maintenance is important for success in this role.

Create a website for me please. Use existing website as reference

We are looking for a highly experienced ReactJS Developer to join us in building a SaaS product from end to end.
This is a serious SaaS development project, and we are looking for someone who can go beyond frontend development and understands complete SaaS architecture, multi-tenancy, backend development, and AWS deployment.
🏷️ Product
Product: SaaS Platform — End-to-End Web Application
We are building a scalable SaaS platform designed to support multiple businesses/organizations and their users through a secure multi-tenant architecture.
The selected developer will be involved in building the product from the architecture stage through production deployment.
💻 Required Skills
Frontend — Primary Requirement
• ReactJS — REQUIRED
• Next.js
• JavaScript / TypeScript
• Responsive UI development
• Component-based architecture
• State management
• REST API integration
• Performance optimization
• Clean and scalable frontend architecture
Backend
• Node.js
• Express.js
• REST API development
• Authentication & authorization
• Database design
• API security
• Backend architecture
• Error handling and logging
🏢 SaaS Architecture — REQUIRED
The candidate must have a strong understanding of SaaS architecture and preferably hands-on experience building multi-tenant applications.
Experience with:
• Multi-tenant architecture
• Tenant isolation
• Organization/workspace architecture
• User management
• Role-based access control (RBAC)
• Authentication & authorization
• Subscription architecture
• Scalable database architecture
• API architecture
• Security best practices
• SaaS scalability
☁️ AWS — REQUIRED
Strong practical AWS experience is required.
The developer should be capable of taking the application from development to a secure production environment on AWS.
Experience with:
• EC2
• ECS / Docker
• RDS
• S3
• CloudFront
• Route 53
• IAM
• Load Balancer
• VPC
• CloudWatch
• Auto Scaling
• CI/CD
🏗️ Responsibilities
You will be responsible for:
• Understanding product requirements
• Contributing to SaaS architecture
• Developing the ReactJS/Next.js frontend
• Developing backend services with Node.js/Express
• Designing and implementing APIs
• Implementing authentication and authorization
• Building multi-tenant functionality
• Designing database structures
• Implementing user, organization, and tenant management
• Integrating third-party services
• Setting up AWS infrastructure
• Deploying the application to production
• Setting up CI/CD
• Monitoring and troubleshooting the application
• Optimizing performance and scalability
• Maintaining clean, scalable, production-ready code
⭐ Ideal Candidate
We are looking for a Senior ReactJS Developer who also understands the complete SaaS technology stack.
The ideal candidate:
• Has strong ReactJS experience
• Has built production SaaS applications
• Understands Next.js deeply
• Has strong Node.js/Express experience
• Understands multi-tenant architecture
• Has hands-on AWS experience
• Understands database architecture
• Can work on both frontend and backend
• Can make technical architecture decisions
• Can take ownership of a product from 0 → production
• Writes clean, maintainable, and scalable code
❌ Not a Good Fit If
Please don't apply if your experience is limited to:
• Basic React websites
• Frontend-only development
• Simple CRUD applications
• Basic Node.js APIs
• WordPress
• Basic Shopify development
• Deploying applications without understanding AWS
• Working only from pre-built templates
We need someone who can think like a SaaS architect and develop like a senior ReactJS engineer.
📩 How to Apply
Please send:
Name:
SaaS Experience:
Multi-Tenant Architecture Experience:
AWS Experience:
SaaS Products You Have Built:
Live Product Links:
GitHub/Portfolio:
Availability:
Hourly Rate / Project Rate:
If you have personally built and deployed a SaaS product from scratch, please share it.
🚀 We are looking for a long-term technical partner who can help us build and scale this SaaS product from idea to production.

Build an AI-powered backend system to automate data processing and improve workflow efficiency. The system should receive user data, process it using AI, store results in a database, and deliver them through secure REST APIs. You will design and develop the backend, integrate AI services, implement authentication, and create a reliable, scalable API. The ideal freelancer can build a stable foundation for future growth and ensure secure, efficient data handling.

I’m building Straitmoor, an AI-powered logistics SaaS platform, and need a full-stack developer to help finish and productionize the existing product.

Stack: React, TypeScript, Supabase/PostgreSQL, APIs and AI integrations.

Main work:

• Fix and complete existing functionality
• Shipment and document management
• AI document extraction and validation
• Email/inbox intelligence
• Live Operations: tracking-provider integrations, shipment events, status and ETA updates
• Alerts and automated workflows
• Dashboard and UI improvements
• Testing, reliability and production readiness

I’m looking for someone reliable who writes clean code, communicates clearly and can work independently in an existing codebase.

Work will start with defined milestones. Strong performance can lead to ongoing development.

Please include relevant SaaS projects and what you personally built.

Hi, would you be able to build me something similar to this for my shopify website?

https://ninjatransfers.com/apps/ninja-gang-sheet?variant=45253165908051

We are looking for an experienced Full-Stack Developer to help improve and refine an existing web application.

The project is already set up, so you'll be working within an existing codebase rather than building everything from scratch. The main focus will be on implementing UI improvements, fixing frontend and backend issues, and making sure the application is clean, responsive, stable, and consistent.

Tech Stack
React.js
TypeScript
Node.js
Express.js
MongoDB

What You'll Do
Work within the existing full-stack codebase
Implement frontend UI improvements and fixes
Fix bugs and improve existing functionality
Make backend/API changes when required
Work with MongoDB and existing data/models
Write clean, reusable, and maintainable code
Ensure the application is responsive and consistent
What We're Looking For
Strong experience with React.js, Node.js, and MongoDB
Good understanding of TypeScript
Experience working with existing codebases
Ability to quickly understand requirements and implement them accurately
Strong attention to detail
Ability to write clean and reusable code

The task is relatively small and straightforward for an experienced full-stack developer. You'll receive access to the existing project and detailed requirements after hiring.

Budget: $30 fixed price

Please apply with a short description of your full-stack development experience and 1–2 relevant examples of previous work.

DO NOT APPLY UNLESS YOU ARE DOING 100% OF THE WORK YOURSELF. ABSOLUTELY NO AGENCIES UNDER ANY CIRCUMSTANCES!!!

In this role you will be an integral part of an already well-established and vibrant development team! We are looking for full-time employees that are able to work in Eastern Standard Time with our team located in Toronto, Canada. Multiple meetings throughout the workday required.

What we are looking for:
- 3+ years of backend experience such as Node.js, MongoDB, Express.js
- BSc. or MSc. in Computer Science (or related field)
- Understanding of APIs (design and deployment), UI development (using Angular), UX awareness, modern charts and graphs

You fit the following criteria:
- Operate in a fast-paced environment while writing high-quality code
- Work closely with the Chief Product Officer to plan and implement new features
- Can own large features from early prototype to a polished final implementation
- Turn a design document into a technical plan, and implement it

Our Tech Stack:
- Back-end Technologies: MongoDB, Express.js, Node.js
- Front-end Technologies: Angular
- Hosting: AWS, Hostwinds, and Mongo Atlas

Our Core Development Principles:
- High-Quality: Develop systems that are flexible and abstract
- Stability: Contribute code that is stable, scalable, and reliable
- Reliability: Developers are responsible for ensuring code is bug-free
- Exploration: Approach hard problems with an inquisitive mind
- Usability: All user-facing systems provide optimal user-experience

Join us on our mission! We look forward to having you join our team!

DO NOT APPLY UNLESS YOU ARE DOING 100% OF THE WORK YOURSELF. ABSOLUTELY NO AGENCIES UNDER ANY CIRCUMSTANCES!!!

Hiring Multiple Developers — Front End / Back End / Full Stack (MERN Stack)
Summary

We're expanding our development team and looking to bring on multiple experienced developers to work on an established, actively maintained platform built on the MERN stack.

We're open to structuring the team in either of the following ways:
- 1 Front-End Developer + 1 Back-End Developer, or
- 2 Full-Stack Developers

Our priority is finding highly capable developers who can contribute to the platform's continued development, security, performance, and scalability.

Front-End Developer

We're looking for someone with strong experience in:
- React
- JavaScript and modern front-end development practices
- Responsive UI development
- API integration
- Performance optimization
- Debugging and improving existing applications
- Writing clean, maintainable, production-quality code

You'll be responsible for building new functionality, improving existing interfaces, resolving front-end issues, and collaborating closely with our back-end developers.

Back-End Developer

We're looking for someone with strong experience in:
- Node.js
- Express.js
- MongoDB
- REST APIs and third-party integrations
- Database design and optimization
- Application security and secure coding practices
- Performance and scalability
- Debugging complex production issues

You should be comfortable reviewing an existing codebase, identifying security, operational, or performance concerns, and implementing the necessary fixes and improvements.

Full-Stack Developer

We're also interested in developers who are genuinely experienced across both sides of the MERN stack and can work comfortably with React, Node.js, Express, MongoDB, APIs, databases, and production infrastructure.

What We're Looking For

We prefer candidates with 5+ years of professional development experience and a proven track record working on production applications.

This is not a one-time project — we're looking for developers who can become ongoing members of our development team. Beyond building new features, we want developers who take ownership of their work, spot potential problems before they escalate, and hold themselves to high standards for code quality, security, reliability, and performance.

We are a UAE-based recruitment agency looking for an experienced full-stack developer to build a lightweight internal Recruitment CRM / ATS for our small team.

This is NOT intended to be a large SaaS platform.

We currently have 3 recruiters and approximately 7–10 active vacancies at a time. We are looking for a simple, reliable and cost-efficient internal system.

CORE FUNCTIONALITY

• Candidate database
• CV/file upload and storage
• Vacancy management
• Custom recruitment stages / pipeline
• Assign candidates to vacancies
• Internal comments and tags
• Candidate activity/history
• Search and filtering
• Duplicate detection
• 3 user accounts
• CSV import/export
• Basic role-based access
• Responsive web interface

HH.RU INTEGRATION — IMPORTANT

hh.ru (HeadHunter Russia) is one of our main sourcing channels.

The system should integrate with hh.ru through its official API.

Our ideal workflow:

1. We already have vacancies published on hh.ru.
2. New applications should automatically appear under the corresponding vacancy in our CRM.
3. Available candidate information, CV/resume and contact information should be imported where permitted by the hh.ru API.
4. We would also like to explore whether candidates found manually through hh.ru resume search can be added to our CRM efficiently.

Because hh.ru API permissions may affect the final functionality, we would prefer the developer to assess the API capabilities before the main development begins.

ACCESSIBILITY

Our company is based in the UAE, while some of our recruiters work from Russia.

The application must therefore be reliably accessible from:

• UAE
• Russia without VPN
• Russia with VPN
• Europe

TECHNOLOGY

We are open to recommendations.

Experience with technologies such as Next.js, React, Node.js, PostgreSQL, Supabase, REST APIs and OAuth would be relevant.

We require full ownership of the source code and infrastructure/accounts used for the application.

WHO WE ARE LOOKING FOR

Ideally an independent full-stack developer who:

• Has previously built a CRM, ATS or internal business tool
• Has strong experience with third-party API integrations and OAuth
• Can handle both frontend and backend development
• Can deploy and maintain a production web application
• Can work independently

Experience with hh.ru / HeadHunter API is a major advantage.

WHEN APPLYING

Please answer:

1. Have you built a CRM, ATS or similar internal management system? Please share examples.
2. Have you worked with OAuth and third-party REST APIs?
3. Have you worked with the hh.ru / HeadHunter API before?
4. What technology stack would you recommend for this project?
5. What would be your approximate timeline?
6. Please provide your approximate FIXED-PRICE estimate for the MVP described above.

We are currently comparing several developers and are looking for a practical MVP rather than an enterprise-level system.

I am looking for a professional web developer to create a modern, responsive, and user-friendly website for my media brand, Geremew Media. The website should work well on mobile phones and computers. I need pages such as Home, About Us, News/Articles, Videos, Contact, and Social Media links. Please make the website easy to update and connect it with my Facebook Page. I am looking for a reliable freelancer who can communicate clearly, deliver high-quality work, and complete the project on time.

We are looking for an experienced Next.js and Node.js developer for an urgent task on our educational visa consultancy website.

The website is already developed. We need someone to work on the existing code and automate the calendar/appointment scheduling system.

Tasks include:

Automating the existing calendar
Working with the Next.js frontend
Working with the Node.js backend
Connecting the calendar with existing APIs and database
Managing appointment availability and time slots
Handling booking and scheduling logic
Fixing any existing calendar-related issues
Making sure everything works properly in production

Requirements:

Strong experience with Next.js and Node.js
Experience with calendar or appointment booking systems
Good understanding of APIs and backend development
Ability to work with an existing codebase
Good debugging and problem-solving skills

This is an urgent task. We need someone who can start immediately and complete the work as quickly as possible.

When applying, please share examples of similar calendar or booking systems you have worked on and mention your availability to start immediately.

We have a working production authentication, licensing, and secure software-delivery platform. We are looking for a senior backend/security engineer to audit the existing implementation, identify meaningful weaknesses, and implement targeted improvements without unnecessarily rewriting the system.

This is not a greenfield project and it is not suitable for “vibe coding.” Do not apply if your normal workflow is to generate large patches you cannot independently explain, test, and defend. We need someone who can trace an unfamiliar codebase, reason about trust boundaries and state transitions, and support conclusions with source-level and runtime evidence.

The private repository and detailed architecture will be shared with shortlisted applicants.

Current technology

- Node.js 20 and TypeScript
- NestJS with Fastify
- PostgreSQL with versioned migrations
- Cloudflare, Workers, and private R2 storage
- nginx and PM2 on a Linux VPS
- Native Windows/C++ clients
- libsodium-based cryptography: X25519, XChaCha20-Poly1305, Ed25519, and Argon2id
- Discord webhooks and a Discord bot management integration

What the system currently does

- User registration and authentication using username, password, and hardware identity
- One-HWID account binding, HWID resets, bans, and blacklisting
- Time-limited and lifetime license keys with delayed activation and expiry enforcement
- Encrypted, signed, replay-resistant client/server sessions
- Session renewal, heartbeat-based authorization, revocation, and logout
- Authenticated entitlement and configuration delivery
- Secure release publication through Cloudflare Workers and R2
- Short-lived authenticated download URLs and one-time web download capabilities
- Signed release metadata with client-side integrity verification before execution
- Separate public and developer release channels
- Scoped management API keys, IP restrictions, and mTLS-protected service/admin routes
- Database-backed auth events, management audit records, file logging, and Discord alerts
- Existing rate limiting and basic abuse/anomaly detection

Initial scope

We want to begin with a paid security and architecture audit. The successful developer may then continue into the remediation and deployment milestones.

1. Security and architecture review

- Trace the complete handshake, login, registration, session, heartbeat, entitlement, launch-ticket, and download flows
- Review trust boundaries between Cloudflare, nginx, the origin, PostgreSQL, Workers, R2, Discord services, and native clients
- Identify exploitable findings, operational weaknesses, race conditions, and inconsistent authorization decisions

2. Rate limiting and abuse prevention

An existing hybrid rate limiter is already present. We want it reviewed and strengthened where necessary.

- Brute-force resistance across IP, account, HWID, and session dimensions
- Persistent enforcement across application restarts
- Safe handling of distributed or multi-process deployments
- Prevention of account-lockout abuse and memory-exhaustion attacks
- Correct rate limiting before expensive password-hashing or cryptographic work
- Session-sharing, replay, automation, and suspicious download detection
- Review of Cloudflare client-IP attribution and spoofed forwarding headers

3. Licensing and entitlement consistency

- Ensure login, heartbeat, renewal, entitlement, launch-ticket, and download routes all use the same authoritative license rules
- Test expiry boundaries, lifetime licenses, delayed activation, extension, revocation, and concurrent requests
- Review transactional behavior and eliminate TOCTOU or race-condition gaps
- Help formalize tier-based entitlements if multiple product tiers are introduced
- Ensure release-channel access cannot be changed through client-controlled parameters

4. Logging, auditability, and monitoring

Logging and database audit records already exist. We want to improve their operational usefulness.

- Structured, searchable server logs
- Request/session correlation without logging credentials, session keys, download URLs, or other bearer secrets
- Reliable audit records for authentication, downloads, releases, and management actions
- Retention and pruning policies
- Alerting for abuse patterns and operational failures
- Bounded retry/queue behavior for important Discord notifications
- Clear separation between security events and expected session-expiry noise

5. API and error handling

- Verify consistent error behavior across pre-authentication and authenticated routes
- Preserve generic login failures to prevent user enumeration
- Keep detailed diagnostics server-side while returning stable client-facing codes
- Review DTO validation, payload limits, malformed envelope handling, and fail-closed behavior
- Avoid breaking the existing wire protocol unless a change is justified and approved

6. PostgreSQL and performance

- Profile real query paths rather than making speculative optimizations
- Review indexes, query plans, connection-pool settings, and transaction boundaries
- Reduce unnecessary database round trips
- Review concurrency and locking around license activation, ticket consumption, release activation, and nonce consumption
- Add safe cleanup strategies for expired sessions, tickets, nonces, leases, and audit data

7. Cloudflare and origin hardening

The public API is already proxied through Cloudflare using HTTPS and Authenticated Origin Pulls. We want the deployment independently validated and hardened.

- Confirm the origin cannot be reached directly from the public internet
- Verify firewall restrictions and Cloudflare IP-range handling
- Validate AOP/mTLS configuration and certificate lifecycle
- Ensure Cloudflare headers are trusted only after the connection has been authenticated
- Review Worker secrets, R2 permissions, cache behavior, and download capability validation
- Verify internal bot/admin routes remain isolated from the public listener

Expected deliverables

- Evidence-backed audit report with severity and exploitability ratings
- Prioritized remediation plan with estimated effort
- Targeted source changes and PostgreSQL migrations
- Automated security, regression, replay, concurrency, and expiry tests
- Updated deployment and operational documentation
- Staging and production deployment support
- Post-deployment verification using fresh logs and runtime evidence
- Clear documentation of any remaining assumptions or residual risk

Required experience

- Strong TypeScript and Node.js backend experience
- Production experience with NestJS or Fastify
- Strong PostgreSQL schema, indexing, transaction, and concurrency knowledge
- Hands-on application-security and authentication-system experience
- Cloudflare Workers, R2, reverse-proxy, TLS, and origin-lockdown experience
- Familiarity with authenticated encryption, signatures, replay prevention, and secure session design
- Linux, nginx, and PM2 production operations
- Ability to review an existing protocol without casually replacing it with a fashionable framework

Native Windows/C++ client experience is helpful but not mandatory.

We have an existing small SaaS web application built with Next.js, TypeScript, Node.js/Express, Prisma and PostgreSQL.

We need a developer to fix a few issues before deploying the latest version to production.

Current Issues

Frontend

After login, the dashboard sometimes doesn't load the user information correctly.
One dashboard API request is being triggered multiple times.
There is a small responsive issue on the dashboard for mobile screens.

Backend

The user profile endpoint occasionally returns an unauthorized response after login.
Authentication/session handling needs to be checked.
One API response needs better error handling.

Database

Review the relevant Prisma query and PostgreSQL relation.
Make sure the correct user data is returned after authentication.
Deployment

Once the application is working correctly locally:

Deploy the Next.js frontend to Vercel
Deploy the Node.js/Express backend to Render
Configure production environment variables
Connect the existing PostgreSQL database
Resolve any CORS/environment configuration issues
Verify the complete production flow
Requirements

Please do not rewrite the application or change the existing architecture.

The goal is to identify the root causes, make focused fixes, test them locally, and deploy the corrected version.

Tech stack:

Next.js
React
TypeScript
Node.js
Express.js
Prisma
PostgreSQL
Vercel
Render
Git/GitHub

Budget: $80 fixed

Please include examples of similar full-stack debugging/deployment work in your proposal.