Engineer · Technical Instructor · Builder of Teaching Systems
I teach engineers, and I build the systems that let great teaching scale.
I’m a programmer who founded Flatiron School and taught its first cohorts myself. As the school grew to 13 campuses, my job became turning what worked in my classroom into curriculum, instructor development, standards, and software so other instructors could deliver the same experience. Today I build with Claude Code and the Claude API every day, and I want to do the same thing for the people learning to build with it.
im@avi.nyc · New York · github.com/aviflombaum · anthropic.resume.avi.nyc
Hands-on AI product development inside a small team of founders, operators, and investors.
Build with Claude Code and the Claude API daily: agents, tool use, structured outputs, prompt versioning, and evals, shipped in production Rails applications.
Built Blastoff Rails, an application generator with an AI development harness of versioned instructions, skills, conventions, hooks, and scripts. The model writes the code and the harness defines the process.
Taught non-engineers on the team to ship product and code through that harness, with review and guardrails that kept quality high. A small field-readiness program in practice.
Built and launched VCMatch, using embeddings over investor portfolios and theses to match founders with relevant investors and explain the fit.
Built PostMoney, which extracts KPIs from founder updates, emails, and PDFs into portfolio reporting. Currently in private beta.
Created PromptEngine, an open-source Rails engine that manages prompts as data with versioning, rollback, and a testing playground for OpenAI and Anthropic models.
Advise four portfolio companies on technical direction and lead Innovent’s CTO Huddle.
Socratic Tutor: an LLM tutor that asks instead of answers, watches for frustration in student responses, and adjusts scaffolding. Ten years of teaching, encoded in prompts.
Technical training at scale: thousands of trainees a year moving through instructor-led programs into engineering roles.
Built eXa, a learning platform for instructor-led technical training, and RevUP, a free preparation course, connecting candidate preparation, live instruction, and progress tracking.
Built a training-event tracking system that connected data across tools so training and marketing teams could see what was working and act on it.
Led a remote product and engineering team of 50. Introduced Ruby on Rails to cut sprint time by 50% and reworked AWS infrastructure to cut cloud costs by 30%.
Helped scale the company from $60M to more than $260M in annual revenue.
Flatiron School
Jun 2012–May 2020
Founder / Chief Technology & Product Officer
From teaching the first class of 20 students myself to building the instructor bench, the curriculum, and the platform that let 13 campuses teach the same way.
Taught
Taught the first cohorts in person and full time: Ruby, Rails, JavaScript, test-driven development, and Git, in labs of 20 and lectures of 100+.
Authored the curriculum and labs that ran across every campus. Concepts connected to executable, test-driven labs, real developer tools, and increasingly independent project work.
Scaled teaching
Built and developed the instructor bench as Flatiron grew from one classroom to 13 campuses: hiring, teaching dry-runs, classroom observation, feedback, and the call on who was ready to lead a cohort.
Started Learn.co from a faculty meeting about curriculum consistency across cohorts. The answer was to put the curriculum in GitHub, make every lab test-driven, and give every instructor the same material and the same signal.
Built Learn.co into a social learning platform: GitHub-backed curriculum, a coding CLI, a browser IDE, live community and TA help, and instructor dashboards. Test results and webhooks gave per-student, per-lesson signal that surfaced struggling students and weak lessons alike.
Set the teaching culture and formats: peer support, public work, constructive feedback, and learning through building. Ran teacher-efficacy surveys so students could tell us how instruction was landing.
Led a 60-person product and engineering organization across six squads, with daily deployments supporting in-person and online programs. Helped scale Flatiron to 600 employees, 10,000+ alumni, and $60M in annual revenue through its $30M acquisition by WeWork.
Learn.co held a 70%+ completion rate online, against single digits for typical online courses. In 2018, 2U entered a $14.5M agreement for a perpetual Learn.co source-code license and integration services.
Program design, curriculum & train-the-trainer guide
Conceived of and designed the program and curriculum with Karlie Kloss. Wrote the teaching guide that let instructors who were not expert engineers run the program well: short explanations followed by exercises, questions rather than taking over, and small, achievable projects.
The program has run every summer since 2015 with a new cohort of instructors each year. The guide is what makes that repeatable.
NYC on Rails
Founder · Founded 2007
Built a community around Ruby on Rails through technical talks, events, and shared work. Where I first learned to explain code to a room.
Designer Pages
Co-founder · 2008–2012
Built a search and specification platform for architects and designers, indexing more than one million products. Patented the ad-matching approach.
03 / Sessions I’ve taught and materials I’ve written
The teaching is the portfolio.
Talks, guides, and a case study, all of them public.
From the KWK teaching guide A rule for helping without taking over.
The problem I have kept returning to is how you transfer technical capability from a small number of experts to a much larger population without lowering the bar. At Flatiron the question stopped being whether I could teach a thing and became whether someone in another classroom, on another campus, with another instructor, would get an equally good experience.
Claude expertise today lives with a small number of people who teach alongside their real jobs. Turning that into an instruction function, with instructors, standards, certification, and measurement, is the same work. This time the subject is the technology I build with every day.