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For Companies At a Glance
- Tasks: Rebuild an AI-first invoicing system from scratch with a focus on clean architecture.
- Company: Join a forward-thinking team dedicated to innovative AI solutions.
- Benefits: Competitive pay, flexible hours, and the chance to work on cutting-edge technology.
- Why this job: Be at the forefront of AI development and shape the future of invoicing.
- Qualifications: Senior-level experience in full-stack development and AI integrations required.
- Other info: Fast-paced project with clear milestones and opportunities for growth.
The predicted salary is between 36000 - 60000 £ per year.
I'm looking for an experienced developer or small team to start working immediately on an AI-first invoicing system. I already have an AI-generated codebase (50k+ lines), but it has become overly complex and hard to maintain. Some parts (mainly web design and selected logic) may be reusable, but the expectation is a clean rebuild from scratch.
Important: The initial task is to estimate scope, time, and cost, and then continue directly into development.
Project flow
- Initial phase (short, paid)
- Review existing code & design
- Propose clean architecture
- Estimate total effort, timeline, and cost
- Split the project into clear milestones
Execution phase
- Development starts immediately after milestone approval
- Payment and delivery handled per milestone
Product overview
The core is an invoice management system:
- Full CRUD for invoices (create, edit, delete)
- Invoice drafts
- Sending invoices (email / export)
- User authentication (register / login / logout)
- Company management (CRUD) – company profile, billing details, branding used across UI and invoices
Key differentiator
All functionality must be accessible both via classic UI and via an AI chat interface. Users should be able to:
- Create, edit, or send invoices by talking to AI
- Use prompts like "create an invoice for client X for last month"
- Modify drafts conversationally
- Manage the system without clicking through forms
The AI layer (ChatGPT / Anthropic) acts as a natural-language interface, translating intent into concrete system actions. The goal is an AI-first invoicing product, where chat is a first-class interface, not an add-on.
What I expect from applicants
- Senior-level experience with full-stack systems
- Ability to estimate realistically, not optimistically
- Experience with AI integrations (LLMs, intent-to-action flows)
- Clear communication and milestone-driven delivery
Please include in your proposal:
- Relevant experience
- How you would approach estimation + build
- Expected timeline for first milestone
This project is intended to move fast, with clear milestones and continuous progress.
Contract duration of 1 to 3 months, with 40 hours per week.
Mandatory skills: JavaScript, API, Artificial Intelligence, AI Agent Development
AI-First Invoicing System employer: FreelanceJobs
Contact Detail:
FreelanceJobs Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land AI-First Invoicing System
✨Tip Number 1
Get your networking game on! Reach out to your connections in the tech industry, especially those who have experience with AI and invoicing systems. A personal recommendation can go a long way in landing that dream job.
✨Tip Number 2
Show off your skills! Create a portfolio showcasing your previous projects, especially any work related to AI integrations or full-stack development. This will give potential employers a taste of what you can bring to the table.
✨Tip Number 3
Be proactive! Don’t just wait for job postings to come to you. Visit our website regularly and apply directly to roles that catch your eye. The more you put yourself out there, the better your chances of landing that gig.
✨Tip Number 4
Prepare for interviews by brushing up on your communication skills. Be ready to discuss your approach to estimation and project milestones, as well as how you would tackle the complexities of an AI-first invoicing system. Confidence is key!
We think you need these skills to ace AI-First Invoicing System
Some tips for your application 🫡
Show Off Your Experience: Make sure to highlight your relevant experience in full-stack systems and AI integrations. We want to see how your skills align with our needs, so don’t hold back on showcasing your past projects!
Be Realistic with Estimates: When it comes to estimating scope, time, and cost, keep it real! We appreciate a straightforward approach, so share your thought process and how you plan to tackle the project milestones.
Communicate Clearly: Clear communication is key for us. In your application, outline how you would keep us updated throughout the project and ensure that everyone is on the same page as we move forward.
Apply Through Our Website: We encourage you to apply through our website for a smoother process. It helps us keep everything organised and makes sure your application gets the attention it deserves!
How to prepare for a job interview at FreelanceJobs
✨Know Your Code Inside Out
Since the job involves working with an existing AI-generated codebase, make sure you review it thoroughly before the interview. Understand its structure, strengths, and weaknesses. This will help you discuss how you can improve it and propose a clean architecture.
✨Be Ready to Estimate Realistically
Prepare to discuss your approach to estimating scope, time, and cost. Think about how you would break down the project into milestones and be ready to justify your estimates with examples from past projects. This shows you can think critically and plan effectively.
✨Showcase Your Full-Stack Experience
Highlight your senior-level experience with full-stack systems during the interview. Be prepared to share specific examples of projects where you've successfully integrated AI and managed both front-end and back-end development.
✨Communicate Clearly and Confidently
Since clear communication is key for this role, practice articulating your thoughts on technical concepts and project management. Use straightforward language and avoid jargon unless necessary. This will demonstrate your ability to convey complex ideas simply.
