Beam Calculator applet example

A local-first calculator pattern for turning repeat engineering-style worksheets into inspectable desktop applets without uploading private project data to a hosted builder by default.

What this example demonstrates

The Beam Calculator page mirrors the content style used across YAAA.app: plain-language inputs, visible assumptions, deterministic formulas, and clear review checkpoints. It is an example workflow, not professional engineering advice.

  • Local inputs: span, load, material notes, and project comments are entered in the applet on the user's machine.
  • Visible math: formulas, units, and intermediate values are shown before export so users can validate the result.
  • Guardrails: missing units, unrealistic ranges, and unsupported cases stop the workflow instead of producing confident-looking output.
  • Evidence: results can include a timestamped note showing assumptions, reviewer status, applet version, and validation checks.
Step 1

Capture inputs with unit labels

Use structured fields for span, distributed load, support condition, and units. The applet should reject ambiguous entries rather than guessing.

Step 2

Show calculations before actions

Display the formula path and assumptions in a readable panel. If AI assisted the setup, keep generated explanations editable and reviewable.

Step 3

Export a cautious report

Export notes with disclaimers, version information, and a required reviewer field. Do not present example output as certified design.

Manifest-first applet shape

A calculator applet starts with a manifest and a declared entrypoint. If it later exports notes, the manifest should request that capability and the user should approve it before the applet writes files.

applet.json
{
  "applet_id": "com.example.beam_calculator",
  "version": "0.1.0",
  "publisher_id": "pub.example",
  "language": "python",
  "entrypoint": "main.py",
  "capabilities": []
}

main.py
def hello():
    return True

Why make calculators as local applets?

Teams often have private spreadsheets, project names, drawings, and assumptions embedded in calculation tools. A YAAA-style local applet can keep that workflow close to the user's files, call approved local scripts, and use optional services only when explicitly configured.

Explore more applet patterns → · Review local-first security notes → · Read the disclaimer →