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Driven and self-reliant software developer with a robust background in IT, and proven communication skills. Brings a wealth of experience in the managed IT, reprographic, manufacturing, and library industries. Known for sharing insights gained from this background to improve operational maturity. I'm skilled at bringing technological solutions to business problems.

I’m a developer with a can-do attitude and extensive experience with a variety of game engines and coding languages. My specialties are bug fixing, optimization, and rapid prototyping. I look forward to working together!

Since 1991 I have focused on writing quality business software. My specialties are in the areas of finance, investing, blockchain and insurance. I have strong C/C++, C#, and Java/J2EE skills. I am comfortable developing for Windows, Unix/Linux, and mobile platforms. I have worked extensively with Microsoft SQL Server, Oracle, kdb+ and MySQL database management systems and am confident in my skills. While I do take on UI work, I spend most of my time on back-end services that are performant, scalable and fault tolerant.

✅ 𝗠𝘂𝗹𝘁𝗶𝗽𝗹𝗲 𝟳-𝟴 𝗳𝗶𝗴𝘂𝗿𝗲 𝘀𝘂𝗰𝗰𝗲𝘀𝘀𝗲𝘀 & 𝗦𝗮𝗮𝗦 𝗰𝗹𝗶𝗲𝗻𝘁𝘀/𝗮𝗽𝗽𝘀 𝗮𝗰𝗾𝘂𝗶𝗿𝗲𝗱. ✅ 𝟳𝟱+ 𝗮𝗽𝗽𝘀 𝗯𝘂𝗶𝗹𝘁. 𝟭𝟭+ 𝘆𝗲𝗮𝗿𝘀 𝗽𝗿𝗼𝗳𝗲𝘀𝘀𝗶𝗼𝗻𝗮𝗹 𝗲𝘅𝗽𝗲𝗿𝗶𝗲𝗻𝗰𝗲. ✅ 𝗔𝗰𝗰𝘂𝗿𝗮𝘁𝗲 & 𝗴𝘂𝗮𝗿𝗮𝗻𝘁𝗲𝗲𝗱 𝗾𝘂𝗼𝘁𝗲𝘀 𝘄𝗶𝘁𝗵 𝟯𝟬-𝟰𝟬% 𝗹𝗼𝘄𝗲𝗿 𝗰𝗼𝘀𝘁𝘀 𝗮𝗻𝗱 𝗱𝗲𝘃 𝘁𝗶𝗺𝗲𝘀 𝘁𝗵𝗿𝗼𝘂𝗴𝗵 𝗽𝗿𝗼𝗽𝗿𝗶𝗲𝘁𝗮𝗿𝘆 𝗳𝗿𝗮𝗺𝗲𝘄𝗼𝗿𝗸 𝘂𝘀𝗲(prebuilt-SaaS code). ✅ 𝗣𝗵𝗲𝗻𝗼𝗺𝗲𝗻𝗮𝗹 𝗰𝗼𝗺𝗺𝘂𝗻𝗶𝗰𝗮𝘁𝗶𝗼𝗻 𝗮𝗻𝗱 𝗽𝗿𝗼𝗷𝗲𝗰𝘁 𝗺𝗮𝗻𝗮𝗴𝗲𝗺𝗲𝗻𝘁 𝘀𝗸𝗶𝗹𝗹𝘀. 𝗜𝗻𝘁𝗲𝗹𝗹𝗶𝗴𝗲𝗻𝘁 𝗱𝗲𝘃 𝗽𝗿𝗼𝗰𝗲𝘀𝘀 𝗳𝗼𝗹𝗹𝗼𝘄𝗲𝗱 𝗯𝘂𝗶𝗹𝘁 𝘁𝗵𝗿𝗼𝘂𝗴𝗵 𝗼𝘁𝗵𝗲𝗿 𝗽𝗿𝗼𝗱𝘂𝗰𝘁 𝘀𝘂𝗰𝗰𝗲𝘀𝘀𝗲𝘀. ✅ 𝗦𝗰𝗮𝗹𝗮𝗯𝗹𝗲 𝘀𝗼𝗹𝘂𝘁𝗶𝗼𝗻𝘀, 𝗲𝗻𝘁𝗲𝗿𝗽𝗿𝗶𝘀𝗲-𝗿𝗲𝗮𝗱𝘆 𝗳𝗿𝗼𝗺 𝗹𝗮𝘂𝗻𝗰𝗵. ✅ 𝗨𝗦 𝗰𝗹𝗶𝗲𝗻𝘁 𝘀𝗽𝗲𝗰𝗶𝗮𝗹𝘁𝘆. Hi, I’m Andrew! I specialize in delivering polished SaaS apps consistently focused on earning revenue. 𝗜𝗻𝘃𝗶𝘁𝗲 𝗺𝗲 𝘁𝗼 𝘆𝗼𝘂𝗿 𝗽𝗿𝗼𝗷𝗲𝗰𝘁 𝗼𝗻 𝗨𝗽𝘄𝗼𝗿𝗸 𝗼𝗿 𝘀𝗲𝗻𝗱 𝗺𝗲 𝗮 𝗱𝗶𝗿𝗲𝗰𝘁 𝗺𝗲𝘀𝘀𝗮𝗴𝗲 𝗮𝗻𝗱 𝗶𝗳 𝘁𝗵𝗲𝗿𝗲’𝘀 𝗮 𝗹𝗶𝗸𝗲𝗹𝗶𝗵𝗼𝗼𝗱 𝗼𝗳 𝗮 𝗴𝗼𝗼𝗱 𝗳𝗶𝘁 𝘁𝗼 𝘄𝗼𝗿𝗸 𝘁𝗼𝗴𝗲𝘁𝗵𝗲𝗿, 𝗜’𝗹𝗹 𝗶𝗻𝘃𝗶𝘁𝗲 𝘆𝗼𝘂 𝘁𝗼 𝗯𝗼𝗼𝗸 𝗮 𝗰𝗼𝗺𝗽𝗹𝗶𝗺𝗲𝗻𝘁𝗮𝗿𝘆 𝗰𝗼𝗻𝘀𝘂𝗹𝘁𝗮𝘁𝗶𝗼𝗻 𝗰𝗮𝗹𝗹 𝘁𝗼𝗴𝗲𝘁𝗵𝗲𝗿. 🗣 𝗝𝗼𝗵𝗻 𝗠𝘂𝗹𝗹𝗲𝗻𝗵𝗼𝗹𝘇 - 𝗛𝗲𝗮𝗱 𝗼𝗳 𝗦𝗮𝗹𝗲𝘀, 𝗦𝘁𝗿𝗮𝘁𝗲𝗴𝗶𝗰 𝗘𝗻𝘁𝗲𝗿𝗽𝗿𝗶𝘀𝗲 - 𝗨𝗯𝗲𝗿 𝗘𝗮𝘁𝘀 ❝ Andrew is the most skilled freelancer and developer I have ever worked with, and I have worked with a lot. He was able to take very broad ideas and turn them into actionable insights and plans in a way I could never imagine was possible. Andrew is the best possible thing to happen to our business and the definition of a true professional. I could not recommend him enough. Anyone who has the opportunity to work with Andrew should consider themselves extremely lucky. ❞ I excel at expertly guiding the app dev process to max out your revenue-earning potential in contrast to your costs, and to steer you away from common SaaS app pitfalls. Client Outcome Examples: ⚡ amzalert.com (8-Figure Acquisition - Rebuilt In 4 Months) ⚡ launchcontrol.us (8-Figure Annual Recurring Revenue - ARR) ⚡ GuestBan.com (Concept-To-Live in 5 Months - 1M+ Monthly App Checkins) My support is based on hard-won successes built through more than a decade of SaaS app obsession. Most of my clients are: ☑️ Existing Businesses - Post-revenue ☑️ Solopreneurs & Small Teams - Wanting to build an MVP app ☑️ Funded Startups - Focused on turning funding into MRR ☑️ Existing Early Stage SaaS - Want to rebuild and scale up I’m the founder of a small, hand-picked team of talented humans. I’m personally involved in all projects, and we only employ senior developers and native English speakers from the US for project management and communication. My team and I are able to consistently reduce dev costs by about 30-40% by leveraging pre-built development frameworks for common app experiences like the user login or checkout, for example, while reserving valuable dev hours for truly custom functionality. Every project we build delivers: 📱Cross Device Compatibility - Desktop - Mobile - Tablet 📈 App Speed Optimization 🧩 Scaleable - Cost-Effective Feature Addition Potential 🛡️ Security 📊 User Analytics & Internal Dashboards 🌐 Multi-Language Localization 🤖 Quality Assurance - QA 📜 Paid User Subscription, Billing & Renewal Management Thanks for taking the time to learn more about me. Invite me to your project or send me a direct message if you’re interested in working together. Talk soon! Andrew Mace - Founder - Lean Engineering Highlights of the work I have extensive experience in includes: SaaS MVP • AI Automation • No-Code/Low-Code • Process Automation • RPA • .NET 8 • Python • AWS • Azure • Docker • Serverless • OpenAI / ChatGPT • Generative AI • Zapier • Make.com • UiPath • Power Automate • n8n • Bubble • Airtable • Stripe • PayPal • Twilio • Slack • Teams • REST APIs • Webhooks • SQL • PostgreSQL • Redis • Power BI • KPI Dashboards • ETL • Airflow • Real-Time Chat • Push Notifications • Subscription Billing • CRM Integration • Lead Generation Bots • Data Analytics • Digital Transformation • Workflow Automation • Rapid Prototyping

Specialized in Systems Analysis and part-time maintenance (up to 20-30 hours/week) for legacy Powerbuilder / Oracle / Sybase / MS SQL Server environments. Productive on Day One. With over 20 years of specialized experience in PowerBuilder (v6.5 through v2022) and complex database environments, I provide the rare expertise needed to maintain, debug, and enhance mission-critical legacy applications. I specialize in the "plumbing" of legacy apps—ensuring stable SQLCA.DBMS connectivity and data integrity during system transitions. I possess the unique ability to step through established "black box" applications with little to no training, providing immediate value. Beyond coding, I bridge the gap between legacy systems and future goals by documenting existing functionality for developers, business analysts, and stakeholders to assist in eventual modernization strategies. Core Competencies: PowerBuilder Mastery: Expert work with PB versions 6.5, 8, 12.5, and 2016+, including the DIAMOND® Enterprise System and PFC frameworks. Database Expertise: Senior-level SQL, SQLCA.DBMS configuration, and Stored Procedure development for Oracle (Legacy to 19c), Sybase (v10, v12), and SQL Server. Modernized Documentation: I leverage modern AI-assisted tools to accelerate the analysis and summarization of legacy PowerScript logic, ensuring every finding is manually verified for technical accuracy. Industry Knowledge: Deep experience including Health Insurance (Diamond), Manufacturing, POS Systems, and Compliance Reporting. Whether you need urgent bug fixes, long-term system maintenance, or a technical guide to assist your modernization strategy, I am at ease collaborating with DBAs and Project Managers to deliver stable, documented results. Whether you need urgent bug fixes, long-term system maintenance, or a technical guide to assist your modernization strategy, I am at ease collaborating with DBAs and Project Managers to deliver stable, documented results.

I work across AI, data engineering, backend development, and cloud infrastructure. Most of the projects I take on involve a lot of moving parts, so I'm comfortable owning the full stack instead of just one piece of it. I build LLM apps, RAG systems, AI agents, MCP integrations, document search, internal knowledge tools, workflow automation, and custom SaaS features. I work with OpenAI, Claude, Gemini, LangChain, LangGraph, FastAPI, Node.js, React, and vector databases. On the data side, I build ETL/ELT pipelines, API integrations, data migration workflows, and backend services that move data between databases, files, SaaS platforms, and cloud systems. I pay a lot of attention to validation, retries, logging, reconciliation, and making sure the data is actually clean when it gets where it needs to go. I also have experience with healthcare systems and sensitive data. That includes HIPAA-related workflows, PHI, access control, audit logs, secure APIs, data migration, and integrations where security and traceability matter. For RAG and LLM work, I handle document parsing, chunking, embeddings, hybrid search, reranking, citations, structured outputs, tool calling, permissions, evaluation, and monitoring. I can also build MCP servers when an agent needs controlled access to internal tools, APIs, databases, or business systems. Main stack - Python, FastAPI, Django, Node.js, C#/.NET - React, Next.js, Angular, Vue, TypeScript - OpenAI, Claude, Gemini, LangChain, LangGraph, MCP - RAG, AI agents, vector search, pgvector, Pinecone, Weaviate - PostgreSQL, SQL Server, MongoDB, Redis - ETL/ELT, data migration, APIs, workflow automation - AWS, Azure, GCP, Docker, Kubernetes, Terraform - Healthcare, HIPAA, PHI, secure integrations If you have an AI or data project that's getting messy, slow, or hard to maintain, I can usually help straighten out the architecture and get it into production.