Andy A. Kifer
Renaissance Fullstack Engineer
Seasoned engineer with more than 10 years of experience. I work in SaaS platforms, APIs and most recently in Machine Learning / AI backed applications. Full skills and reflexes upgraded with LLMs agentic workflows.
Skills & Expertise
1. Core
Ruby / Ruby on Rails
2008 — Today- I discovered Ruby in 2006, and I've been since building stuff with the language in every possible ways.
- I began professional Rails development since Rails 3. I acquired deep expertise with all the iterations of the framework, up to date with today's Rails 8 and Hotwire.
- ActiveRecord beyond the basics, Arel, advanced SQL techniques, caching schemes, DSLs and Metaprogramming, Horizontal and Vertical Scaling, Sidekiq, REST and GraphQL APIs, Postgresql, TDD/BDD, Hotwire, StimulusJS, React, ViewComponent, Phlex, TailwindCSS, Kamal, Docker, CI/CD, Git, Claude, Cursor ... you name it, been there, did it.
2. Wider exposure
Python | Elixir-OTP | Clojure | web3
2012 — Onward- I worked on different projects for US startups and companies when I was member of the Toptal, 10X Management professional networks.
- Python: for Fullstack/Backend/API projects (Django, DRF, FastAPI, Flask, Pytest, Celery), AI / data engineering (Pandas, scikit-learn, PyTorch), and edge stuff (FizzBee, Vyper)
- Elixir: Continuation of my Ruby/Rails passion into the land of functional programming and actor model (OTP, Phoenix, LiveView, Axon/Nx)
- Clojure: inherited from my long lasting story with LISP languages (Common Lisp, Scheme/Racket). For the win, I believe that hyperfiddle/electric is at the apex of full stack web-engineering, and Datomic is an awesome datastore.
- Got my hands involved in various other technologies thoughout my career: microservices, serverless, blockchain, web3 applications, Golang, Rust, HPC, TLA+, q/kdb+/shakti
3. The Renaissance
AI & Machine learning ➜ ANY STACK
2025 — Now- I was of the generation that stared in awe when we saw that scene from the Matrix movie for the very first time (Neo: 'Guns, lots of guns') ... and dreamed to have a copy of Jarvis like Tony Stark. Now we have it, the gates were opened, and the possibilities are endless.
- I embrace AI tooling: Claude, Cursor, Codex, Agents, let's use them for our great good (because why not)!
- I practice AI augmented engineering: humans at the command for judgement and accountability, AI doing the heavy load. We couldn't even dream anything close to that 10 years ago.
- I pursue a wide range of intellectual interests (AI, Quantum Computing, Robotics, Manufacturing 4.0, the next wave) via the community, keeping myself up to date with the latest research and academic publications.
- We live in a new era, I learn continuously, and I will become who I need to be.
Featured Projects
DesignFiles
DesignFiles connects your design work, sourcing, invoicing, and client communication in one system — so you can take on more projects without burning out. I worked in the team as a Senior backend and API engineer.
Silverfin
Cloud Post-Accounting and Compliance for Accounting Firms. I was a Lead engineer for the API integrations team there. Worked with global clients like EY, KPMG, Deloitte.
Rsportz
Technology & Marketing Platform for Global Sports Federations. Serving 40+ countries. Senior Ruby on Rails developer in the engineering team for 5 years.
Open Source
My whole tech career wouldn't be possible without the open source tooling and community, and I am infinitely grateful for that. I gave back to that awesome global community with my little share as well: a ruby gem to play with the SP500 stocks index, a couple of Binary Search related libraries, just to name a few
About Me
Hi, I’m Andy Kifer. I have a solid track record of building and scaling mission critical applications, from concept to launch and beyond. I acquired deep expertise in fullstack engineering, excel in end to end ownership and solid engineering process. I've built and maintained scalable architectures, worked with AI/LLMs and complex workflows, used to do technical/academic research reviews and connect the results to market needs. I enjoy the creative thinking, the system level work, the collaboration with the people, the kind of stuff that AI will never replace: a human expert judgement and accountability. And still having a lot to learn along the way.
