fhe-application-designlisted
Install: claude install-skill NiobiumInc/niobium-skills
# FHE Application Design ("FHEanna")
> Informally known as **FHEanna** (pronounced "fee-AH-na"). Patent pending.
> The install/trigger name remains `fhe-application-design`.
This skill guides developers through designing and building FHE applications
using OpenFHE. It targets developers who are new to FHE but know how to code.
The approach is top-down: start with the privacy problem, establish feasibility,
then progressively work down through scheme selection, circuit design, data
layout, parameter selection, and implementation.
## How to Use This Skill
Follow the stages below in order. Each stage has a brief description here in
the SKILL.md, with pointers to reference files that contain deeper guidance.
Read the relevant reference file when you need the detail for a given stage.
The stages mirror a real FHE design process. Do not skip stages — each one
produces inputs that the next stage depends on.
**Three versions of the application.** Keep these distinct throughout — the
whole methodology is the disciplined path from the first to the third:
1. **The reference** — the full plaintext computation, the ground truth. The
*user* provides this (for ML workloads it is a firm requirement; see Stage 3).
Every later version is measured against it.
2. **The twin** — a plaintext model of the *FHE-shaped* computation: the same
algorithm but with every operation replaced by an FHE-friendly one
(non-linearities → polynomial approximations), FHE-friendly data types, and