Full-stack & AI Engineer

* This is a part-time role (25 hours/week) for a 1-month contract

* You will join a project-based engagement to deliver a proof of concept for a private legal research and document-editing platform, built to run over a law firm's own files and client records

* Confidentiality drives every decision: secure document handling, local infrastructure, and tightly controlled use of cloud-based LLM APIs

* The POC will cover 1-2 high-value workflows, to be finalized at kickoff, likely among search and retrieval across a private document collection, AI-assisted legal research, AI-assisted document analysis and editing, supplying relevant document context to an LLM, and a simple, practical web application wrapping these capabilities

* The intended architecture is primarily local: a web application running inside the client's environment, documents stored on a NAS, local indexing and search, secure retrieval, and OpenAI and/or Anthropic APIs invoked only with the minimum context required for each response

* You will help validate and refine that architecture instead of implementing a predetermined design, and you will operate with a high degree of independence, taking a high-level business objective from a non-technical client and turning it into a working product

* The POC succeeds when the client has a functional, secure application demonstrating the core workflow, can test it against representative documents, and has enough confidence to define what gets built next

* There is potential for continued development, maintenance, and future upgrades

* So, your responsibilities will be:

* Own the technical execution of the POC, from requirements through delivery

* Design and build the web application supporting the legal research workflow

* Implement document ingestion, indexing, search, and retrieval

* Integrate LLM APIs (e.g., OpenAI, Anthropic) into the application flow

* Validate and refine the proposed local/private architecture

* Implement security and privacy controls for confidential material

* Define what data can and cannot be sent to external APIs

* Deploy and document the initial application

* Address findings raised in a security-focused code review before delivery

* Work directly with the client to capture business requirements

* Translate business requirements into practical technical solutions

* Help define and prioritize the initial POC scope

* Manage development priorities and timeline independently

* Report progress and technical decisions directly to the client

* 5+ years of software development experience

* Experience building full-stack web applications

* Experience building LLM-powered applications with APIs (e.g. OpenAI, Anthropic)

* Experience with retrieval technologies (e.g. RAG, embeddings, semantic search, vector databases)

* Experience with document and data ingestion, indexing and search

* Proficiency with backend and API development

* Ability to architect, build and deliver a full project independently

* Deep understanding of application security and sensitive-data handling

* Strong communication skills in both spoken and written English

* Startup experience

* Freelance or consulting experience

* Experience working directly with non-technical clients

* Experience running projects end-to-end, from requirements to delivery

* Experience building AI-powered document applications

* Experience in LegalTech or with legal documentation

* Experience with enterprise search or knowledge-management systems

* Experience with on-premise or hybrid cloud architectures

* Experience with NAS and local infrastructure

* Experience handling confidential or otherwise sensitive data

* Bachelor's Degree in Computer Engineering, Computer Science, or equivalent

Hiring from: Argentina, Brazil, Colombia, Mexico, Paraguay, Chile, Peru, Costa Rica, Uruguay.