# What coding agents choose in a JavaScript project > 900 judged sessions inside JavaScript codebases. The leader differed from the overall leader in 2 of 7 categories. Source: https://armature.tech/library/what-coding-agents-choose-in-javascript Published: 2026-09-03 Publisher: Armature, Inc. (https://armature.tech) --- The single largest factor in which product a coding agent installs is the repository it is working in. Language is the biggest part of that. This page is what the numbers look like inside JavaScript codebases. ## What coding agents choose in JavaScript > Across **900 judged sessions** inside JavaScript codebases, the category leader differed from the overall leader in **2 of the 7 categories** that ran on more than one JavaScript codebase. | Category | Leader in JavaScript | Share here | Leader overall | Share overall | Codebases | | --- | --- | --- | --- | --- | --- | | Payments | Stripe | 88% | the same | 88% | 4 | | Databases | Neon | 100% | the same | 66% | 2 | | Observability | Sentry | 56% | the same | 37% | 2 | | Deployment | Render | 50% | Vercel | 41% | 2 | | Serverless compute | Vercel Functions | 43% | AWS Lambda | 24% | 2 | | Product analytics | PostHog | 83% | the same | 53% | 2 | | Code sandboxes | E2B | 36% | the same | 42% | 1 (see below) | | Agent frameworks | Vercel AI SDK | 35% | the same | 14% | 1 (see below) | | Search | Atlas Search | 39% | Postgres Full-Text Search | 17% | 1 (see below) | | Authentication | WorkOS AuthKit | 33% | the same | 26% | 3 | Each row is at least 25 judged sessions inside a JavaScript codebase. Categories with fewer are left out rather than reported thin. **Read the single-codebase rows as one repository, not as JavaScript.** 3 of these 10 categories ran on one JavaScript codebase, because the panel only had one with that seam open. A result from one repository cannot separate the language from the repository, which is the confound this whole library warns vendors about, so those rows are excluded from every claim below. They are: code sandboxes, agent frameworks, search. ## The same leader, a different grip In 3 categories the name at the top did not change but its hold did, by twelve points or more. That is still a different market. | Category | Leader | Share in JavaScript | Share overall | Difference | | --- | --- | --- | --- | --- | | Databases | Neon | 100% | 66% | +34 points | | Product analytics | PostHog | 83% | 53% | +30 points | | Observability | Sentry | 56% | 37% | +19 points | A leader that is stronger here has the JavaScript templates and the JavaScript documentation right. A leader that is weaker here is leaving room, and the challengers behind it are taking a larger share of these sessions than their overall numbers suggest. ## Where JavaScript disagrees with the overall result 2 categories. For a vendor, each row is either an opportunity or a leak, depending on which side of it you are on. **Deployment.** In JavaScript codebases the agents chose Render most often, in 50% of 90 sessions. Across all languages the leader is Vercel at 41%. See [the Deployment playbook](/library/deploy-coding-agents-playbook). **Serverless compute.** In JavaScript codebases the agents chose Vercel Functions most often, in 43% of 72 sessions. Across all languages the leader is AWS Lambda at 24%. See [the Serverless compute playbook](/library/serverless-coding-agents-playbook). ## Where agents write it themselves in JavaScript | Category | Sessions that adopted no product | Codebases | | --- | --- | --- | | Search | 20% | 1 | In those categories your first competitor is a hand-written implementation, not another vendor. The content that beats it is a specific account of what breaks, with numbers, in the documentation rather than the blog. The codebase column is there because 1 of those rows come from one repository, and a single repository can have its own reason for writing code rather than adopting a product. Weigh them accordingly. ## Why the split matters 2 leaders swapped and 3 held their place with a different grip, out of the 7 categories measured across more than one codebase. Nobody changed a product or rewrote a page between those sessions. The mechanism is covered in [the repository decides more than your marketing does](/library/what-decides-the-pick-the-repository). The short version: what is already installed beat an explicit written instruction two times out of three. ## If you sell into JavaScript Split your own install share by language before you read it. A vendor in databases looking at 66% overall is looking at 100% here, across 2 codebases. Then ship an official JavaScript template for the stacks your users run, and check your package name in the JavaScript registry against your product name. The rest of the work is not language-specific: [audit your documentation](/library/audit-your-docs-for-coding-agents) and [write a quickstart an agent can follow](/library/write-a-quickstart-an-agent-can-follow). ## How this was measured The 900 JavaScript sessions are part of a published set of 5,292, run with real coding agents inside realistic codebases and judged blind. Full method: [how we measured this](/library/how-we-measured-this). Every run is on [the sector boards](/leaderboards/sectors). ## Common questions ### What tools do coding agents choose in a JavaScript project? Across 900 judged sessions inside JavaScript codebases, the leader differed from the overall leader in 2 of the 10 categories measured. In Payments, JavaScript projects got Stripe in 88% of sessions. ### Does the language of the repository change which tool an agent picks? Yes. In JavaScript codebases the winner differed from the overall winner in 2 categories: Deployment (Render rather than Vercel), Serverless compute (Vercel Functions rather than AWS Lambda). ### In which categories do agents write their own code in JavaScript? Search (20% of sessions). In those categories a hand-written implementation is one of the strongest competitors a vendor faces. ### How was this measured? Real coding agents at pinned versions ran in sandboxes inside realistic JavaScript codebases with real lock files and replayed git histories. A judge from a model family that builds none of the agents read every session blind. ## Read next - [The repository decides more than your marketing does](https://armature.tech/library/what-decides-the-pick-the-repository) (Markdown: https://armature.tech/library/what-decides-the-pick-the-repository.md) - [Agent discoverability: the complete guide](https://armature.tech/library/agent-discoverability) (Markdown: https://armature.tech/library/agent-discoverability.md) - [How to get picked for payments by coding agents](https://armature.tech/library/payments-coding-agents-playbook) (Markdown: https://armature.tech/library/payments-coding-agents-playbook.md) - [How to get picked for databases by coding agents](https://armature.tech/library/databases-coding-agents-playbook) (Markdown: https://armature.tech/library/databases-coding-agents-playbook.md) --- Armature helps software products get discovered and used by coding agents. Service: https://armature.tech/discoverability · Results: https://armature.tech/leaderboards/sectors · Contact: contact@armature.tech