---
title: "Accelerate required type checking with a native compiler"
description: "Linear switched its type check to tsgo, the native TypeScript compiler."
url: https://starsling.dev/ci-playbooks/techniques/native-type-checking
canonicalUrl: https://starsling.dev/ci-playbooks/techniques/native-type-checking
---

# Accelerate required type checking with a native compiler

Linear switched its type check to tsgo, the native TypeScript compiler.

## How to choose an approach

This technique currently has one documented company example. Validate its prerequisites, tradeoffs and original CI environment against your repository before adapting it.

- **[Linear](https://starsling.dev/ci-playbooks/linear#native-type-checking)**: Use it when A qualifying no-emit type check is the long-running step on the merge path. Check before adopting: Compiler API consumers and changed defaults need a compatibility plan. Keep both checks until outputs match; emitting builds do not qualify for this recipe.

## Apply this technique

````text
Evaluate and apply this CI technique to my repository: Accelerate required type checking with a native compiler.

Linear switched its type check to tsgo, the native TypeScript compiler.

Read the technique and its source-backed company examples: https://starsling.dev/ci-playbooks/techniques/native-type-checking.md

Inspect this repository’s CI workflows, build and test commands, dependencies, and recent run timings. Identify where this technique applies and explain the expected benefit using this repository’s evidence.
Measure a baseline from recent comparable runs: elapsed time, queue time, runner minutes and failures where available. If data is unavailable, say what cannot be measured.
Compare relevant company approaches, checking prerequisites, platform differences and tradeoffs. Rank applicable options by evidence, fit and measurable opportunity; do not present company results as predictions for this repo.
Recommend the smallest safe change, show what checks and fallback paths remain, and ASK ME WHICH CHANGE TO APPROVE BEFORE EDITING ANY FILES.
Only after approval, work on a new feature branch, make one reversible change, and open a reviewable pull request. Never merge or push to a default or protected branch.
Keep required checks, test coverage, deployment and release behavior intact. Validate the change and compare equivalent runs where possible; report limitations and what should be monitored after merge.
````

## How Linear used this technique

Read what Linear changed and follow the original sources.

### Linear: Accelerate required type checking with a native compiler

Linear switched its type check to tsgo, the native TypeScript compiler, and the weekly median of the tsc check fell 73%. The published prompt translates that change into the catalog’s TypeScript 7 compatibility checks.

Evidence: Documented technique

Use it when: A qualifying no-emit type check is the long-running step on the merge path.

Before applying it: Compiler API consumers and changed defaults need a compatibility plan. Keep both checks until outputs match; emitting builds do not qualify for this recipe.

[Read more in the Linear playbook](https://starsling.dev/ci-playbooks/linear#native-type-checking)

[Primary source](https://linear.app/now/ci-bottleneck-reworked#upgraded-infrastructure-and-tooling)

## CI optimization is continuous work.

Apply this technique yourself, or use StarSling Runners for faster GitHub Actions and optional agent-driven optimization PRs, which teams on eligible paid plans can turn on.

[Get self-improving CI](https://starsling.dev/products/runners)

## Related techniques

### [Use a faster native linter without losing rules](https://starsling.dev/ci-playbooks/techniques/native-lint-tools)

Move supported lint checks to a fast native implementation and preserve coverage for rules it does not support.

2 implementations · 2 companies (Linear, Spotify)

## Company Playbooks

### [Anthropic](https://starsling.dev/ci-playbooks/anthropic)

Run only affected tests

### [DoorDash](https://starsling.dev/ci-playbooks/doordash)

Run build and test in parallel, sharded across CI agents

### [Linear](https://starsling.dev/ci-playbooks/linear)

Benchmark the same job on faster hardware

### [Mastra](https://starsling.dev/ci-playbooks/mastra)

StarSling runners for the slowest test workflow

### [OpenAI](https://starsling.dev/ci-playbooks/openai)

Rank CI fixes by the minutes they save

### [Ramp](https://starsling.dev/ci-playbooks/ramp)

Move a CPU-bound test suite to a faster CPU

### [Shopify](https://starsling.dev/ci-playbooks/shopify)

Let an agent iterate against one CI metric

### [Spotify](https://starsling.dev/ci-playbooks/spotify)

Build arm64 on native arm64 runners

### [Stripe](https://starsling.dev/ci-playbooks/stripe)

Run only the tests a change can reach

### [Uber](https://starsling.dev/ci-playbooks/uber)

Build the merge-queue speculations most likely to be needed