blobatar

Deterministic geometric blobatars from any string. No dependencies, ~4.4 KB gzipped.

bun add blobatar    # npm / pnpm / yarn all work too

Usage

A blobatar always stands for somebody — a user, a bot, a team, a repo — so the value it is generated from is that somebody's name: a username, a display name, an email, a handle, an id. Any string works, and the same string always renders the same blobatar.

React

bun add blobatar @blobatar/react

import { Blobatar } from "@blobatar/react";
<Blobatar name={user.email} size={48} />;

Everything but name is optional. Remaining props land on the underlying element, so className, alt and the rest behave as you would expect.

Vue

bun add blobatar @blobatar/vue

<script setup>import { Blobatar } from "@blobatar/vue";</script>
<template>  <Blobatar name="alain@example.com" :size="48" /></template>

The same props and the same behavior as the React adapter. Anything not declared as a prop lands on the underlying element, so class, style, alt and the rest behave as you would expect.

Svelte

bun add blobatar @blobatar/svelte

<script>  import { Blobatar } from "@blobatar/svelte";</script>
<Blobatar name="alain@example.com" size={48} />

Svelte 5 or newer. This package ships its component as source rather than as built JavaScript, because a .svelte file only becomes renderable code inside your own compiler — any toolchain that resolves the svelte export condition handles that with no configuration, and one that does not reports an unresolved import naming the package rather than handing your bundler a file it cannot execute. See ADR-0010.

Solid and Preact

bun add blobatar @blobatar/solid     # or @blobatar/preact

import { Blobatar } from "@blobatar/solid";
<Blobatar name={user.email} size={48} />;

The React section with the import swapped, which is the whole difference — each is compiled by its own framework's JSX transform rather than re-using React's, so solid-js reactivity and Preact's runtime both behave as they should.

React Native and Expo

bun add blobatar @blobatar/react-nativenpx expo install react-native-svg          # or bun add react-native-svg

import { Blobatar } from "@blobatar/react-native";
<Blobatar name={user.email} size={48} />;

Expo needs nothing beyond that install. An Expo app is a React Native app, and react-native-svg is the same library in both, so there is no @blobatar/expo and there is not going to be one.

Two differences from every other adapter, and both are the platform rather than the package:

size is required. On the web, omitting it lets CSS size the element and the viewBox scales to whatever the page decides. React Native has no such fallback, so an unsized blobatar is a blank square. Defaulting it here was the alternative and it is the one thing an adapter may never do: a default size is a default that changes the picture, and the core is the only place a default is written down.

There is no animate. Blobatar's idle motion is a stylesheet: motion.css, a root class, and a dozen seeded custom properties the CSS reads. React Native has none of the three. The prop is absent from the type rather than accepted and ignored, so passing it is a compile error instead of a blobatar that silently sits still.

expression does work, in full. A static pose bakes into the geometry, which is why it survives here for the same reason it survives in the string API. What is missing is only the morph between poses, which was always the part that needed CSS.

Everything else is the same: same names, same options, same blobatar. Anything not declared as a prop lands on the underlying <Svg>. title becomes the accessibility label rather than a <title> element, because react-native-svg has none. Without one the tree is hidden from screen readers, which is the same call aria-hidden makes on the web.

Flutter and Dart

flutter pub add blobatar

import 'package:blobatar/flutter.dart';
AnimatedBlobatar(  name: user.email,  size: 64,  animation: BlobatarAnimation.always,  options: const BlobatarOptions(    background: Backdrop.squircle,    expression: happy,  ),)

The official Dart/Flutter SDK lives in packages/flutter. It ports the generation-2 core rather than calling into JavaScript, renders native Canvas paths, and includes static and animated widgets. Its checked-in reference vectors pin blobatar 2.4.0; the seed-to-look mapping is unchanged. See the package README for parity evidence, supported platforms, reduced-motion behavior, and the pure Dart calculation API.

shadcn/ui

The registry serves shadcn's Avatar with a blobatar as the fallback for a missing profile image:

npx shadcn@latest registry add @blobatar=https://blobatar.dev/r/{name}.jsonnpx shadcn@latest add @blobatar/avatar

Or straight from this repository, without registering anything:

npx shadcn@latest add Alain00/blobatar/avatar

That reads main, so it is the current composition rather than the last released one. Both forms copy the same file.

import { Blobatar } from "@/components/ui/blobatar";
<Blobatar name={user.email} src=https://raw.githubusercontent.com/Alain00/blobatar/main/%7Buser.avatarUrl%7D />;

That Blobatar is not the adapter's — it takes a src alongside the name, and everything the adapter takes goes in a blobatar prop. A project using both imports one of them under another name.

It is also all that gets copied into your project: the composition, which you own and edit. The generator stays in blobatar and @blobatar/react, installed as ordinary dependencies — a copied-in generator would be pinned to whichever generation you took it from, and the whole point is that a name renders the same picture everywhere.

Five more items are interface built out of that avatar, each one a composition you own after installing it:

npx shadcn@latest add @blobatar/presence-avatarnpx shadcn@latest add @blobatar/agent-listnpx shadcn@latest add @blobatar/user-tablenpx shadcn@latest add @blobatar/password-fieldnpx shadcn@latest add @blobatar/group-chat

presence-avatar is a face with a presence dot and an unread badge, animated, plus a thinking state that adds a three-dot loading indicator. agent-list is the aside an agent runner needs, built on it. user-table is a table of people with a static blobatar per row. password-field is a password input with a face that watches the caret while you type and goes sleepy when you reveal what you typed, which is the one item built on blobatar/gaze. group-chat is a thread with consecutive messages grouped under one face. All five are rendered, with the command that installs each, at blobatar.dev/components.

Anywhere else

blobatar() returns SVG markup as a string, and blobatarUri() wraps it in a data: URI for <img src> or background-image:

import { blobatar } from "blobatar";import { blobatarUri } from "blobatar/uri";
blobatar("alain@example.com"); // '<svg xmlns="..." viewBox="0 0 100 100">…'
el.style.backgroundImage = `url("${blobatarUri(user.id)}")`;

The main entry also carries the palette and trait utilities. If all you do is render, import the renderer on its own and save about a kilobyte:

import { blobatar } from "blobatar/blob";

Configuring

Options are the same across every adapter and the string API. background, hue and tone cover the common cases; traits pins any individual axis as the 0–1 position the hash would otherwise have produced:

<Blobatar name={user.email} background="circle" hue={210} size={48} />;
// Always a sun with wide eyes — colour and everything else still per name.blobatar(user.email, { traits: { shape: 0.95, "eye.ratio": 0 } });

Keys you leave out still come from the name — lock the two things that carry your brand, and every user still gets their own creature. Pin everything and the name stops mattering, which is how you build one fixed blobatar.

Every value those options take, and what each one draws:

Animation and expressions

Both are opt-in. animate idles the blobatar — breathe, bob, blink, glance — and expressions are imported as values so you ship only the poses you use:

import { Blobatar } from "@blobatar/react";import { happy } from "blobatar/expression";import "blobatar/motion.css"; // required — nothing animates without it
<Blobatar name={user.email} animate="hover" expression={happy} size={64} />;

The same props work in every adapter — only the component import changes. The one exception is React Native, which has no animate. See that section above.

The eyes can also follow the cursor. That layer is the one piece of the motion system that needs JavaScript, so it is a separate entry point and a second stylesheet you opt into:

import { useGaze } from "@blobatar/react/gaze";import "blobatar/gaze.css";
const { ref } = useGaze({ travel: 3, lookAt: "pointer" });<Blobatar ref={ref} name={user.email} animate="always" size={200} />;

Every adapter has it, under the shape its framework reaches an element with — same options, same targets, same layer:

useGaze({ travel: 3, lookAt: "pointer" })          // React    → refuseGaze({ travel: 3, lookAt: "pointer" })          // Preact   → elementRefuseGaze(blobRef, { travel: 3, target: "pointer" }) // Vue      → takes your refcreateGaze({ travel: 3, target: "pointer" })       // Solid    → is the refgaze({ travel: 3, target: "pointer" })             // Svelte   → {@attach}

Each package's README has the two-line integration. Anywhere else, gaze(svgEl) is the same thing without the binding.

npx shadcn@latest add @blobatar/password-field is a worked example of it.

Coming from blobatar/react or blobatar/vue

Those subpaths still work and render exactly the same component — the packages above re-export them. They are deprecated and go in v3. Move whenever it suits you:

bunx blobatar-codemod .bun add @blobatar/react   # and/or @blobatar/vue

animate changes the rendering mode: a static blobatar is a single <img>, an animated one is inline SVG. Use "hover" in a grid and "always" for the single-blobatar case. Motion respects prefers-reduced-motion.

Over HTTP

No install and no build step — a URL that renders one:

<img src="https://blobatar.dev/avatar/alain00?size=48" width="48" height="48" alt="">

The path segment is the name, percent-encoded, and the query string is the options under the names the library gives them — size (or s), background, hue, tone, expression, title, gen:

https://blobatar.dev/avatar/alain%40example.com?size=64&background=squirclehttps://blobatar.dev/avatar/team-rocket?expression=smug

Gravatar's d, f and r are accepted and ignored, so an existing Gravatar URL becomes a blobatar by changing the host and nothing else:

- https://www.gravatar.com/avatar/<hash>?s=200&d=identicon+ https://blobatar.dev/avatar/<hash>?s=200&d=identicon

The hash is used as the name. It is one-way, so the email cannot be recovered — but it is itself derived from the email, so each person still gets one stable blobatar of their own. It will not be the same one /avatar/<email> gives: pick one scheme per application.

gen picks the shape vocabulary. New silhouettes cannot be added without reshuffling existing ones — the thresholds partition a single range — so they arrive as a new generation instead:

An unversioned URL follows the current package major and now renders gen 2. Pin ?gen=1 on existing URLs that must keep the original six shapes:

https://blobatar.dev/avatar/alain00?gen=1https://blobatar.dev/avatar/alain00?gen=2

A generation that has appeared in a URL keeps answering. The list only ever grows: gen=1 will not be retired, redirected to a newer vocabulary, or answered with a placeholder, because a URL that renders someone's face is usually written down somewhere its author no longer controls. That is what naming a generation buys, and it is why a pinned URL earns a year-long immutable cache rather than a day — it cannot come back different. The cost falls on the endpoint, which depends on every frozen package major it still serves; the library itself carries only the current one.

GET /avatar/ returns the whole parameter list as plain text, which is the reference this section is a summary of.

Deploy your own

blobatar.dev/avatar is free to use, but it is one small Worker rather than something you have an agreement with, and it is rate-limited. If avatars are load-bearing for you, run the endpoint yourself. The button clones apps/api into your GitHub or GitLab account and deploys it to your Cloudflare account — no configuration, no card, about a minute — and you get:

https://blobatar-api.<your-subdomain>.workers.dev/avatar/<name>

Attach your own hostname afterwards in the Cloudflare dashboard, or as a routes entry in wrangler.jsonc, and every push to your clone redeploys.

It stays inside the Workers free plan for anything short of real scale: 100,000 requests a day, and a blobatar costs 12µs of CPU against the 10ms allowed per request and 357 gzipped bytes to send. There is no database, no bucket and no state — the avatar is a pure function of the URL, which is also why every cache between you and it does the actual work.

Full docs — options table, guarantees, and how it works →

Workspace

bun installbun dev        # tuning grid   → localhost:3001bun site       # landing page  → localhost:3000bun api        # the endpoint  → localhost:8787/avatar/alainbun test       # library testsbun run check  # tests + size budgetsbun run media  # redraw the README images (needs Chrome + ImageMagick)

CONTEXT.md is the glossary — worth two minutes before changing anything, since shape and the name/seed split mean specific and easily-confused things here. Architectural decisions live in docs/adr/.