Node.js vs Deno vs Bun: Which Should You Use in 2026?

The fastest way to lose a JavaScript runtime debate is to bring a benchmark to it. Node.js, Deno and Bun all run npm packages, all ship a package manager, and all now claim to be the fastest option on the table. But the number that should actually decide which one you pick in 2026 is not requests per second. It is who is still funding the project in three years, because a runtime you have to migrate off is far more expensive than a runtime that starts a few milliseconds slower.

The Benchmark Race Is Already Decided, and That's the Least Interesting Part

Start with what is not in dispute: Bun is fast. On its own site, Bun reports that a fresh install of a medium-sized project takes 1.41 seconds with bun install, against 18.12 seconds for the same project with npm. It also publishes an Express.js throughput test showing 48,243 requests per second against 25,181 for Node.js on the same hardware. Those are vendor numbers, so treat them as a ceiling, not a guarantee.

An independent test from the developer tools company Better Stack, using its own Express.js benchmark rather than Bun's, found a similar ordering but different magnitudes: Bun at 52,479 requests per second, Deno at 22,286, and Node.js at 13,254 in that specific scenario. The exact multiplier moves depending on who runs the test and which framework sits on top, but the ranking does not: Bun first, Deno second, Node third, in essentially every throughput test that gets published.

None of that tells you whether Bun is the right choice for your team. Plenty of production Node.js APIs are bottlenecked by a database query or a third-party call, not by the runtime's own request handling. If your service spends 200 milliseconds waiting on Postgres, shaving a few milliseconds off HTTP dispatch will not show up in your latency graphs.

npm Compatibility Is Where the Real Trade-off Lives

Node.js is the reference implementation of the API every npm package is written against, so compatibility there is not a question. The interesting comparison is what happens when Deno and Bun try to run the same code.

Deno spent its first few years as a deliberately Node-incompatible alternative, which kept its ecosystem small. Deno 2 reversed that: according to Deno's own site, it now supports npm specifiers (import express from "npm:express"), reads standard package.json and node_modules layouts, and can even read lockfiles from pnpm and yarn. That single change is arguably the most consequential thing that happened to Deno since its 2018 launch, because it removed the main reason teams avoided it.

Bun's compatibility story is different: it runs on JavaScriptCore (Safari's engine) rather than V8, and its own documentation is candid that "if a package works in Node.js but doesn't work in Bun, we consider it a bug in Bun," backed by running Node's own test suite before every release. That matters most for framework-heavy stacks: a project built on Next.js 16, for instance, still expects the underlying runtime to behave like Node in edge cases, so compatibility gaps show up as framework bugs, not runtime bugs. The gaps that remain are specific rather than vague: Bun does not support native Node.js addons (compiled .node files), has partial node:crypto support because it uses BoringSSL instead of OpenSSL, and stubs out some profiling and async-hooks APIs. If your dependency tree includes a native addon such as certain image-processing, database-driver or hardware-access libraries, that is a hard blocker, not a performance tax.

Anthropic Buying Bun Changes the Backing Calculus

On December 2, 2025, Anthropic announced it had acquired Bun, according to the official Bun blog and corroborated by independent coverage from TechCrunch. The announcement is explicit that Bun "stays open-source and MIT-licensed," that the same engineering team keeps building it in public on GitHub, and that its roadmap continues to focus on Node.js compatibility and replacing Node as the default server-side runtime. Anthropic's stated interest is infrastructure: Bun now underpins tooling like Claude Code, giving the runtime a well-funded corporate sponsor with a direct product incentive to keep investing in it, rather than relying on venture funding that eventually needs a return.

Deno took the more traditional path: the Deno Company was seeded with backing that included Mozilla Corporation, according to Deno's own announcement, and it has explicitly rejected an "open core" model, promising to keep the runtime itself permissively MIT-licensed rather than gating features behind a paid tier. That is a reasonable, well-precedented structure, but it still depends on a venture-funded company eventually finding a sustainable commercial product (Deno Deploy, its hosting platform, is that bet) rather than a large company treating the runtime as core infrastructure.

Node.js sits apart from both. It is governed by the OpenJS Foundation, formed in 2019 when the Node.js Foundation merged with the JS Foundation under the Linux Foundation, according to the Linux Foundation's own press release. Its member-supporters include IBM, Google, Microsoft, GoDaddy and Netflix. No single company can unilaterally redirect Node's roadmap or fold it into an unrelated product. That vendor-neutrality is slower and less exciting, but it is the reason Node has been a safe multi-decade bet for enterprises that cannot tolerate a single company's acquisition risk.

How We Chose What to Compare

This comparison is based on the runtimes' own official documentation and release pages (bun.sh, deno.com, nodejs.org), the primary announcement of the Bun acquisition, an independent throughput benchmark from Better Stack, and Linux Foundation press materials on Node.js governance. We did not run our own performance tests; where a number could not be confirmed against an official source or at least one independent reputable source, it was left out rather than repeated from aggregator blogs.

Which One Should You Actually Use

Use this as a decision rule rather than a ranking, since the three runtimes are not really competing for the same job anymore:

• Choose Node.js if: you are running an existing production codebase, you depend on native addons or obscure npm packages, or your organization needs a vendor-neutral runtime with no single company able to change the rules. Run the current Active LTS release (v24, "Krypton," as of September 2026) rather than the Current release (v26), which is still in its pre-LTS window.
• Choose Bun if: you are starting a new service, care about cold-start latency (serverless functions, CLIs, edge workers) and install/build speed in CI, and your dependencies do not include native addons. The Anthropic acquisition removes most of the "will this get abandoned" risk that used to be the main objection.
• Choose Deno if: you want TypeScript with zero build configuration, a default-deny security sandbox for running untrusted or third-party code, and you are comfortable with a smaller (though now npm-compatible) ecosystem and a venture-backed company behind it.
• Skip switching entirely if: your current runtime is not causing you a measurable problem. Migrating a working Node.js service to chase a benchmark number is a common way to spend two sprints solving a problem you did not have.

The Honest Counterpoint: Sometimes Speed Really Is the Point

The argument above downplays benchmarks, and that deserves pushback. For a narrow set of workloads, raw runtime speed is not a vanity metric: serverless functions billed per millisecond on the kind of managed platforms covered in our cloud hosting guide, command-line tools that users invoke hundreds of times a day, and build tooling that runs on every CI job all multiply small per-invocation savings into real time and cost. If your Lambda-style function's own cold start dominates its total latency, or your CI pipeline's install step is the slowest part of every pull request, Bun's install and startup advantages are not marketing, they are a legitimate operational win. The steelman case for choosing on speed alone is strongest exactly where the runtime itself, not a downstream API or database, is the bottleneck.

Where that argument breaks down is generalizing from those cases to "always pick the fastest runtime." Most backend services are not runtime-bound, and the migration cost, engineer ramp-up time, and compatibility debugging of switching a mature codebase off Node.js routinely exceeds any latency gain a switch would produce. Treat speed as a tiebreaker for new, narrowly-scoped services, not as the primary criterion for an existing system.

What to Watch Next

Watch two things over the next year. First, whether Anthropic's ownership visibly redirects Bun's roadmap toward AI-tooling use cases at the expense of general web backend features, since that is the risk implicit in any single company owning a general-purpose runtime. Second, whether Deno's npm compatibility actually closes real-world migration gaps in practice, or whether teams that try it still hit edge cases severe enough to send them back to Node. Both are answerable with a small pilot project rather than a full migration: pick one non-critical internal service, port it, and measure your own install times, cold starts and dependency failures before betting a production system on the switch. That kind of incremental, benchmark-your-own-workload approach is consistent with the broader shift we've tracked in what's actually changing in web development in 2026, where teams increasingly treat tooling churn as a cost to be managed rather than a trend to chase.

Sources

• Bun official site
• Bun licensing documentation
• Bun Node.js API compatibility documentation
• Bun blog: Bun is joining Anthropic
• TechCrunch coverage of the Anthropic-Bun acquisition
• Deno official site
• Deno blog: Announcing the Deno Company
• Node.js release schedule and version status
• Linux Foundation: Node.js Foundation and JS Foundation merge to form OpenJS Foundation
• Better Stack: Node.js vs Deno vs Bun comparison and benchmark