---
title: "Production-grade TypeScript"
description: "Michael Arnaldi defines production-grade software through reliability, observability, testability, and maintainability."
plain: "Michael Arnaldi calls software production-grade when it stays resilient, observable, testable and easy to change."
group: concept
terms:
  - "production-grade TypeScript"
  - "production-grade software"
sources:
  - url: https://youtu.be/apklpPEgZgw?t=205
    title: "Michael Arnaldi - Effect: Production-Grade TypeScript - YouTube"
    publisher: "Michael Arnaldi"
    note: "Production-grade definition; used for resilience, testability, and maintainability."
    accessed: "2026-10-01"
  - url: https://youtu.be/BqUnsDnMnMo?t=1357
    title: "Effect Meetup (Part 1 of 3) - SAN FRANCISCO 11/02/2023 - WHY EFFECT? BY MICHAEL ARNALDI - YouTube"
    publisher: "Michael Arnaldi"
    note: "Remix demonstration; used for Schema, context, metrics, and retries."
    accessed: "2026-10-01"
---

# Production-grade TypeScript

> For agents: start with the [agent guide](https://ratstack.sh/llms.txt). Every page is Markdown by default; add `Accept: text/html` for HTML.

New on /news: [Effect Office Hours 52 with Resonate HQ](/news).

Michael defines production-grade software as long-lived software that remains resilient, observable, testable, predictable, modular, and approachable. [CityJS, 03:25](https://youtu.be/apklpPEgZgw?t=205) [06:57](https://youtu.be/apklpPEgZgw?t=417).

Resilient software can recover from failures. Observable software exposes behavior through logs, metrics, and traces.

He demonstrates Effect context, Schema, spans, metrics, and retry policies in a Remix application. [Effect Meetup SF, 22:37](https://youtu.be/BqUnsDnMnMo?t=1357) [30:34](https://youtu.be/BqUnsDnMnMo?t=1834).

See [Effect: Production-Grade TypeScript](/lore/cityjs-effect-production-grade-typescript-michael-arnaldi).

## Sources

1. [Michael Arnaldi - Effect: Production-Grade TypeScript - YouTube](https://youtu.be/apklpPEgZgw?t=205)
   Michael Arnaldi. Production-grade definition; used for resilience, testability, and maintainability. Accessed 2026-10-01.

2. [Effect Meetup (Part 1 of 3) - SAN FRANCISCO 11/02/2023 - WHY EFFECT? BY MICHAEL ARNALDI - YouTube](https://youtu.be/BqUnsDnMnMo?t=1357)
   Michael Arnaldi. Remix demonstration; used for Schema, context, metrics, and retries. Accessed 2026-10-01.

## Linked from

- Agent guide → An Effect stack so pure (aspirational) Kit Langton will blush. → [Read page](https://ratstack.sh/llms.txt)

- Change log → What changed in the files served here, newest first. → [Read page](https://ratstack.sh/log)

- Effect: Production-Grade TypeScript → Michael Arnaldi presents Effect as a set of shared tools for production TypeScript. → [Read page](https://ratstack.sh/lore/cityjs-effect-production-grade-typescript-michael-arnaldi)

- Full agent guide → An Effect stack so pure (aspirational) Kit Langton will blush. → [Read page](https://ratstack.sh/llms-full.txt)

- Rat Stack lore | rat-stack → Short, source-grounded notes on the ideas and decisions behind rat-stack. → [Read page](https://ratstack.sh/lore)

- Source change history (log.md) → The generated change log as Markdown. → [Read page](https://ratstack.sh/log.md)