Paul Levitt

Projects  ·  Case Study

DNA — unified metadata for composable apps

Designed and built DNA, a unified metadata schema, and the compiler that turns it into working application objects — tables, UI, business rules, and more — in real time. It replaced per-type fragmentation inherited from HR.net and became the foundation every other platform service ran on. It also implements the composition mechanism described in US Patent #10,558,436 B2, where I'm a co-inventor.

The Problem

HR.net already delivered one HR platform across multiple countries, but every metadata type had its own storage, structure, and services. Cross-feature enhancements and localizations were achievable, but only up to a point — some still needed custom scripts or copied/duplicated metadata to work around the fragmentation. We built mechanisms within HR.net to ease this, but the underlying per-type fragmentation remained.

As Lifion started greenfield, that was the opportunity to address the root cause rather than keep working around it.

The Goal

  • Unify type definitions, algorithms, and services into a single consistent schema from the start, rather than continuing to patch around per-type fragmentation.
  • Compose the right version of an app per request from shared, layered parts, instead of custom scripts, copied metadata, or duplicate builds.
  • Make localization and customization a configuration-time concern, not a build-time or script-time one.

The Approach

  • DNA — a single schema defining the rules all metadata types follow, replacing the prior per-type fragmentation with one consistent model.
  • Capsules — on top of DNA, metadata objects are grouped into capsules. Every feature has one "global" capsule, always included at runtime, plus one or more capsules scoped to a specific context — typically a localization (e.g., US, GB).
  • Ownership — each piece of metadata is owned by exactly one capsule: global if it's shared or localizable by default (e.g., the base address UI), or a context-specific capsule if it's a localization override (e.g., address UI under the US capsule).
  • Two kinds of layering — localization (the same address-capture UI composed differently for US vs. UK, no duplicate definitions) and cross-feature enhancement (enabling both Time & Attendance and Payroll let Time & Attendance extend Payroll with PTO capabilities — only when both were enabled).
  • Deterministic composition — the same inputs and enabled modules always produced the same output.
  • The compiler — I designed and wrote it myself: the DNA model, the layering/override semantics, and the composition pipeline implementing the core algorithm described in the patent — flattening and hydrating, turning DNA's flat stored format into the hierarchical structure runtime consumers like the UI renderer and business rules engine need. After I handed it off, a team maintained it and added caching to improve reuse of compiled variants in production.

Co-inventor on US Patent 10,558,436 ("Dynamically Composing Products Using Capsules"), which describes this composition mechanism; the compiler is part of how it's implemented in production.

The Impact

  • Every other platform service consumed the compiler — it became the foundation the entire shipped HCM product was built on, not a feature confined to one area.
  • Verified correctness at two levels: unit tests on the composition algorithm itself, and scenario tests confirming compiled output met localization and override requirements.
  • After handoff, the team's caching work targeted production efficiency of compiled variants; I don't have measured performance numbers to cite, so I'm not claiming a specific gain there.

US Patent #10,558,436 B2

Dynamically Composing Products Using Capsules.

Filed Jan. 2016, granted Feb. 2020.
Assigned to ADP, Inc. Public record

Looking for an architect who thinks in primitives?

Happy to talk about platform architecture, metadata-driven design, or getting internationalization right before it becomes expensive. Based in Brooklyn, authorized to work in the US without sponsorship.