# What changed in d3-hierarchy

> 13 changes in d3-hierarchy 2 to 3 from its official release notes, upgrade guides and advisories: 4 breaking, 5 new APIs and options. Each one cited. Sources checked 2026-11-08. HTML: https://unstale.sh/npm/d3-hierarchy/

To see which of these apply to a repository, run `npx @unstale/cli init` in it.

## d3-hierarchy 3

### Breaking changes

- The package now publishes an ES module bundle instead of separate source files. (3.1.3) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v3.1.3)
- The package now requires Node.js 12 or higher. (3.0.0) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v3.0.0)
- The package adopts type: module, changing its module interpretation for developers using it. (3.0.0) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v3.0.0)

## d3-hierarchy 2

### Breaking changes

- Drops support for older browsers, including IE; use d3-hierarchy 1.x or a transpiler for pre-ES2015 environments. (2.0.0) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v2.0.0)

### New APIs and options

- Nodes become iterable, allowing hierarchies to be traversed as iterables. (2.0.0) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v2.0.0)
- The callback now receives the traversal index. (2.0.0) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v2.0.0)
- The callback now receives the traversal index. (2.0.0) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v2.0.0)
- The callback now receives the traversal index. (2.0.0) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v2.0.0)
- Adds a method to find a node in a hierarchy. (2.0.0) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v2.0.0)

### Behavior and default changes

- Hierarchy APIs accept iterables. (2.0.0) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v2.0.0)

### Fixes and other changes

- Fixes behavior for huge circles. (2.0.0) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v2.0.0)
- Fixes a divide-by-zero bug. (2.0.0) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v2.0.0)
- Fixes a divide-by-zero bug. (2.0.0) — [release notes](https://github.com/d3/d3-hierarchy/releases/tag/v2.0.0)