Show HN: Tenno – Markdown and JavaScript = a hybrid of Word and Excel

Original Article ↗ Hacker News Discussion ↗

Concept & Positioning

  • Tenno extends Markdown with inline JavaScript “cells” to mix narrative and computation, aiming to feel like a hybrid of Word and Excel.
  • Many see it as part of the “literate programming” / executable docs lineage, similar in spirit to Jupyter, Observable, Org mode tables, MDX, and other notebook/wikilike tools.
  • Some find the DSL intuitive and ergonomic; others would prefer plain TypeScript/Python or see it as “just” a templating language with variables.

Local vs Web, Storage & Security

  • Several users want a fully local, desktop-style app with files on disk, not a pure web app.
  • The author notes it already runs fully in the browser after first load and has been successfully packaged as a small macOS app; local-first packaging is considered feasible.
  • Corporate security flagged the site as “grayware,” possibly because it executes arbitrary JS via eval().

Data, Tables & Integrations

  • Strong demand for serious table support: large tabular data, cell formulas, derived tables, and Excel-like operations (sums, averages, referencing other tables).
  • Requests include:
    • Integration with Google Sheets (especially public sheets) and/or local tables.
    • Ability to query local SQLite/DuckDB via SQL.
    • Bignum and complex-number support.
  • Some argue calling it an “Excel hybrid” is premature without proper cell expressions and robust tabular tools.

UX, Error Handling & Mobile

  • Users like inline editable controls and simple charting; current chart DSL is seen as under-documented.
  • Error handling is fragile; malformed chart commands or type mismatches can crash or glitch the UI, prompting calls for better validation and error boundaries.
  • Editable fields sometimes lose focus on each keystroke, making interaction frustrating.
  • Mobile experience is poor: non-responsive layout and split-pane make it “unusable” on phones; suggestions include vertical split, mode toggles, or read-only default on mobile.

Naming, Audience & Vision

  • Name “Tenno” overlaps with a game faction, a lake, and a Japanese word; some foresee SEO friction.
  • Debate on target audience: programmers vs power users vs general spreadsheet users. Many believe it should lean into its niche (executable Markdown docs) rather than trying to replace Excel outright.