NJL Design Lab
Build the financial life you actually want.
Planning tools and practical frameworks for clearer decisions, stronger assumptions, and a more intentional path to financial independence.
Model without signup friction.
Compare the tradeoffs that shape the plan.
Decision support without calculator noise.
What NJL builds
Useful models for money and everyday systems.
Use a tool when you need an answer, an article when you need the reasoning, and a repeatable system when the problem keeps returning.
The Lab – Blog
Read source-backed guides on financial independence, investing, family finance, real estate, AI, and risk.
Read The Lab BlogOperate
Reduce friction in time, attention, home routines, and recurring decisions.
Explore Life SystemsFeatured tools
Start with the job you need to do.
Every product page explains platform, maturity, data handling, and the fastest path to a useful first result.
Web and iOSFI Architect
Model your path to financial independence, test assumptions, and compare major life decisions.
Web appDeal Analyzer
Underwrite a property with cash flow, financing, cap rate, IRR, and equity multiple in one workspace.
1% Better
Capture small improvements worth repeating and make useful progress visible across daily life.
My Farmers Market Planner
Cost recipes, plan market sessions, track sales and leftovers, and understand what is making money.
Latest from The Lab Blog
New models and practical guides.
AI & household systems
Household Self-Sufficiency in the Age of AGI
Lower household costs and preserve flexibility through an uncertain AI transition.
AI & financial independence
AGI and Financial Independence
Prepare income, housing, portfolios, and reserves for economic disruption.
Family finance
What It Really Costs to Raise a Child in the US
A source-backed framework for estimating child-related costs and their effect on an FI plan.
Featured two-part series
Financial independence with children
Start with family design and optionality, then translate those choices into a cost model.
Premium spreadsheets
Prefer to own the model and work in the file?
Explore FI planning, debt payoff, budget, and net worth spreadsheets. Etsy handles checkout and delivery.