Swastik Codes docs vs Swagger UI

Swagger UI is the page most developers first see for an API: FastAPI serves it at /docs by default, and swagger-ui-express, @nestjs/swagger and @fastify/swagger-ui add it to Node.js servers. The Swastik Codes docs packages (swastik-codes on PyPI and @swastik-codes/docs on npm) do the same job: your server reads its OpenAPI document and serves a page for it. This page compares the two as of November 2026. Swagger UI facts come from its documentation and the swagger-ui-dist 5.17 package; Swastik Codes facts come from the packages themselves.

Short verdict. Choose Swagger UI if you rely on its plugin system or OAuth 2 login flows, need it to be open source (Apache 2.0), or your team already knows it well. Choose Swastik Codes if you want a much smaller page, documentation that reads like a guide (introduction, sections, code samples in five languages), a separate page for sending requests that works like an API client, and an easy way to edit names, descriptions and grouping without changing your code.

At a glance

Page size

We loaded the files each page needs on 5 November 2026 and measured what the browser downloads.

The difference matters most on phones and slow connections, and for an API that is opened often by people inside a company. Both are cached after the first visit.

Documentation

Swagger UI lists operations under their tags. Each operation expands to show its parameters, request body (as an example or a schema model) and responses. The OpenAPI info.description sits at the top. It is a reference: compact and complete, and familiar to anyone who has used an API before.

Swastik Codes writes a documentation page. An introduction with the base URL and how to authenticate comes first, then sections and folders in the order you choose, then one section per request: what it does, its parameters and body fields as tables (nested fields indented), its responses, a code sample in the reader's language and an example response beside it. Extra Markdown pages (errors, pagination, webhooks) sit under the introduction. It reads more like documentation people write by hand, generated from the same OpenAPI document.

Sending requests

Swagger UI puts Try it out inside each operation: fill in fields, press Execute, and the response appears under the operation with a cURL command for what was sent.

Swastik Codes gives sending requests a page of its own at /swc/collection, laid out like an API client: every request in a folder tree on the left, a URL bar with Send, tabs for params, authorization, headers and body (JSON with beautify, form fields, file uploads), and a response panel with pretty JSON, headers, status, time and size. Each request keeps its edits while you move between requests, and Code shows the request as you have it in five languages. Run in Swastik Codes opens the whole API as a collection in the full app, where you can save requests, write tests and run them.

Both send requests from the reader's browser, so requests to another origin need that server to allow CORS.

Setup and configuration

FastAPI has Swagger UI built in, which is hard to beat: no install at all. In Node.js both need a package and a few lines.

Swagger UI is configured with options in code (swagger_ui_parameters in FastAPI, swaggerOptions in swagger-ui-express), and what the page says comes from your OpenAPI document, so changing a description means changing your code.

Swastik Codes reads an optional swastik-codes.json next to your app. It can rename the API, write the introduction in Markdown, list sandbox and production servers, set an accent colour, group tags into sections, rename or hide individual requests and add Markdown pages, all without touching your routes. The file is re-read when it changes, so you edit it and reload.

Where Swagger UI is the better choice

• OAuth 2 flows. Swagger UI can run an OAuth 2 authorization-code or implicit login in a popup and fill in the token. In Swastik Codes docs you paste a token you already have.
• Plugins. Swagger UI can be extended with plugins and custom layouts. Swastik Codes docs has no plugin system.
• Open source. Swagger UI is Apache 2.0, and you can change it as you like. The Swastik Codes packages are free but proprietary, and their branding stays.
• Zero install in FastAPI. Swagger UI is already there.

Using both

You don't have to choose. In FastAPI, mount(app) adds /swc/docs and /swc/collection and leaves /docs and /redoc alone, so you can try the Swastik Codes pages next to the ones you have. The same is true in Express or NestJS: both packages can be mounted at different paths.

Frequently asked questions

Is Swastik Codes docs a fork of Swagger UI?

No. It is written from scratch: plain TypeScript with no framework, which is why it is about a twentieth of the size. It reads the same OpenAPI 3.0, 3.1 and Swagger 2.0 documents.

Will my existing OpenAPI document work?

Yes. Nothing in your document has to change. Tags become folders, summary becomes the request's name, and descriptions, examples, enums, defaults, $refs and security schemes are all used.

Can I serve the Swastik Codes pages at /docs?

Yes. In FastAPI, create the app with docs_url=None and call mount(app, prefix=""); the pages are then at /docs and /collection. In Node.js pass prefix: '/'.

Related

• Product
• FeatureDocs for your server
• GuideFastAPI documentation beyond Swagger UI, in one line of Python
• GuideAPI documentation for Express, NestJS and Fastify, served by your own app
• FeatureAPI documentation

Spotted something out of date? Email support@swastik.codes and we will correct it.