Bun vs Deno vs Node.js: Speed, Compatibility and Which to Choose

Node.js remains the safest default for most production teams, Bun is the fastest option for npm-heavy workflows and all-in-one tooling, and Deno is the strongest pick when built-in security sandboxing and a zero-config TypeScript workflow matter more than raw npm-package coverage. That answer matters more than usual this month: Node.js 26 is scheduled to graduate to Active LTS status on October 28, 2026, and Node.js 27 enters its six-month Alpha phase the same month, the first release under Node's new one-major-per-year, every-version-becomes-LTS model. With the Node.js LTS line in flux, now is a reasonable moment to check whether Bun or Deno should replace it, or just sit alongside it, in a given project.

Why this comparison matters right now

Node.js 26.0.0 first shipped on May 5, 2026, and under Node's official release schedule it is due to become the Active LTS line on October 28, 2026, while Node.js 24 moves into Maintenance around the same time. This is the last release cycle to follow Node's old twice-a-year, even/odd pattern. As Pandromeda covered in its deep dive on the Node.js 26 LTS release date and the new yearly model, Node.js 27 enters Alpha this October and will be the first version released under Node's new annual cadence, where every major version eventually earns LTS status instead of only the even-numbered ones.

That transition is a useful trigger to re-run the Bun-vs-Deno-vs-Node question, because all three projects have shipped major updates recently: Node ships native TypeScript support without flags, Bun has pushed its all-in-one toolkit further with Bun.sql and a built-in HTTP router, and Deno 2.8+ has continued narrowing the npm-compatibility gap that used to be its biggest weakness.

Startup time and performance: what each vendor actually claims

Cross-runtime benchmarks are the most contested part of this comparison, and the three projects do not agree with each other. Treat every number below as a vendor-reported figure, not an independent or reproducible-by-us result; both Bun and Deno say explicitly that results vary by workload and hardware.

• Bun's own benchmark (run on Linux x64, AMD EPYC 9R14, median of three runs) has Bun's Express-based HTTP server handling 48,243 requests/second over HTTPS, versus 25,181 req/s for Node.js v26.7.0 and 19,243 req/s for Deno v2.9.5, with Bun also using less peak memory (105 MB vs. 142 MB for Node).
• Deno's own benchmark page shows the opposite ranking on its "real-world" and "hello-world" HTTP throughput and p99-latency charts, where it places Deno ahead of both Bun and Node, citing figures such as "2.1x lower p99 latency" and "1.5x faster cold start" since Deno 2.0. Deno's own charts do, however, concede that Bun has lower peak memory in its tests and a faster cold package install (4.9s for Bun vs. 5.3s for Deno).
• Node.js does not publish a competing head-to-head throughput benchmark against Bun or Deno on its official site; its release notes focus on correctness, security fixes and new APIs rather than comparative speed claims.

The honest summary: Bun and Deno each publish benchmarks showing themselves ahead of the other two, measured on their own hardware and workloads, and neither figure should be read as a settled, vendor-neutral result. What is consistent across both vendors' own numbers is that package installs and process startup tend to be faster on Bun and Deno than on Node with npm, because both ship custom installers and skip some of npm's resolution overhead.

Bun vs Deno vs Node.js comparison table

npm and Node API compatibility in practice

Node.js is, by definition, 100% compatible with npm and the Node API, since it is the reference implementation both were built against. Bun's own documentation says Node.js APIs, node_modules, and frameworks including Next.js, Remix, Nuxt, Astro and SvelteKit "work as-is," though Bun's own comparison table is careful to describe Node compatibility as "aiming to be a drop-in replacement" rather than a guarantee — a meaningfully different claim from "fully compatible." Deno's homepage describes itself as "a fast, open-source, fully Node-compatible JS runtime," and documents support for package.json, tsconfig.json, ESM, CommonJS, node:* imports and npm/yarn/pnpm lockfiles, while resolving packages from a global cache instead of a per-project node_modules folder by default.

In practice this means: if a project depends on obscure native npm modules or Node internals, Node.js itself is still the lowest-risk choice. If the stack is a standard web framework plus common npm packages, both Bun and Deno now claim broad enough coverage that migration is realistic, but neither vendor claims 100% parity, and edge cases (native addons, less common built-in modules) are where compatibility issues still turn up.

Built-in tooling: bundler, test runner and package manager

This is where Bun and Deno most clearly differentiate themselves from Node. Node.js ships a package manager (npm) and, since Node 20, a built-in test runner (node:test) with subtests, mocking, snapshot testing and multiple reporters — but no bundler; projects still reach for Vite, esbuild or webpack for that.

Bun bundles all four roles into a single binary: bun run as the runtime, bun install as the package manager, bun test as a Jest-compatible test runner, and bun build as a bundler with a dev server and hot module reloading, plus a --compile flag that produces single-file executables. Bun's own positioning is that it can replace Node plus npm/yarn/pnpm plus Jest/Vitest plus esbuild/Vite/webpack, or be adopted one piece at a time.

Deno ships a comparably broad toolbox — package management, a test runner, a formatter, a linter, a task runner, a type checker, a coverage tool, a workspace manager, a benchmarking tool and a documentation generator — but deliberately omits a bundler, arguing it isn't needed because TypeScript and JSX run directly from source. Deno's standout built-in feature outside the standard toolchain is its permissions system: file, network and environment access are blocked by default and must be explicitly granted with flags like --allow-net, which has no direct equivalent in Node or Bun.

TypeScript support compared

All three runtimes now run TypeScript without a separate tsc compile step, but the depth of support differs. Node.js added native type-stripping, stable without a flag since Node 22.18.0: it removes "erasable" TypeScript syntax — type annotations, interfaces, type aliases, import type — and executes the resulting JavaScript, but it does not type-check the code, ignores tsconfig.json at runtime, and cannot strip syntax that generates runtime behavior, such as enum, parameter properties or namespaces with runtime code; those still need a separate transpile step.

Bun's own comparison table describes its TypeScript support as "first-class, including paths, enum, namespace," meaning it handles the syntax Node's type-stripping cannot, directly, with no build step and no ts-node. Deno runs TypeScript and JSX "straight from source" as well, and additionally offers full type-checking on demand through deno check, something neither Node's type-stripping nor Bun's transpilation performs automatically at runtime.

Licensing and governance

All three runtimes are released under the MIT license, so licensing itself is not a differentiator for most teams. Governance is where they diverge. Node.js is a project of the OpenJS Foundation, a vendor-neutral foundation whose Cross Project Council coordinates technical governance across hosted JavaScript projects, and whose board includes elected community members and member-company representatives — a structure designed so no single company controls Node's roadmap.

Bun is MIT-licensed at its core, though its binary statically links Apple's JavaScriptCore/WebKit engine, which is LGPL-2 licensed; Bun's own licensing docs explain how to relink the binary with a modified JavaScriptCore to stay compliant. Development happens in the open on GitHub under the oven-sh organization. Deno is also MIT-licensed and developed by Deno Land Inc., the company that also operates the commercial Deno Deploy hosting product — a more conventional single-company-plus-open-source model than Node's foundation structure.

Which JavaScript runtime should you choose?

There is no universally correct answer, but the trade-offs are fairly consistent across all three projects' own documentation:

• Pick Node.js for existing production codebases, teams that need the broadest possible npm and hosting-platform compatibility, regulated environments that favor foundation governance over a single vendor, and anyone who wants to ride out Node 26's move to Active LTS without taking on migration risk.
• Pick Bun for new projects where install speed and an all-in-one toolchain (runtime, package manager, test runner, bundler) matter, especially if the team is comfortable relying on a single project's own published benchmarks rather than independently verified numbers.
• Pick Deno for security-sensitive workloads where sandboxed permissions are valuable, for teams that want type-checked TypeScript without extra tooling, or for projects already deployed on Deno Deploy.

It's also common to mix runtimes by task: using Node.js in production for compatibility while using Bun locally for faster installs and test runs, for example. None of the three require an all-or-nothing commitment, and all three can read the same package.json-based projects to varying degrees.

What next

The most concrete near-term date is October 28, 2026, when Node.js 26 becomes Active LTS — the version most production teams should standardize on going forward, as detailed in Pandromeda's coverage of the Node 26 LTS timeline. Teams evaluating Bun or Deno should treat vendor benchmarks as directional rather than definitive, run their own workload-specific tests before migrating, and check npm/package compatibility against their actual dependency tree rather than general compatibility claims. For teams juggling multiple language runtimes alongside their JavaScript stack, Pandromeda's guide to containerizing applications with Docker covers one common way to run Node, Bun or Deno services side by side without conflicts, and keeping toolchains current matters here too — see Pandromeda's recent look at what's new in Git 2.56 and how to update for one example of staying current on the rest of the development toolchain.

Written byFelix Moreau

Felix Moreau writes Pandromeda's software coverage and how-to guides. He covers Windows, macOS and Linux updates, the apps people rely on, emulators and developer tools, and turns official documentation into clear, numbered steps that work on the current version.

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