MImicroflash·Apr 3, 2024Submission
Fern: Toolkit to generate SDKs and Docs for your API
2 points · Open discussionfern-api
fern
TypeScript2022–2024
fern-api / fern
fern
Input OpenAPI. Output SDKs and Docs.
7Distinct people
12Mentions
0Explicit recommenders
3.8KGitHub stars
What to know before exploring
What it is
Input OpenAPI. Output SDKs and Docs.
GitHub
Where it is used
No documented product use has been verified yet.
What people are saying
No recommendation phrase was found in the indexed comments.
No classified warning is attached to this page. Read the discussions before treating silence as approval.
Also in these discussions
No other repository is repeatedly linked in the same discussions.
This week on Hacker News
Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 12:54:37 PM UTC.
No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.
Mentions over time
HN mentions by month12 dated mentions
Observed mentions: 2022-06-30 04:07:33 UTC to 2024-04-03 16:10:26 UTC.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| Jun 2022 | 2022-06-01 00:00:00 UTC | 2022-07-01 00:00:00 UTC | 1 | 1 | 0 |
| Jul 2022 | 2022-07-01 00:00:00 UTC | 2022-08-01 00:00:00 UTC | 0 | 0 | 0 |
| Aug 2022 | 2022-08-01 00:00:00 UTC | 2022-09-01 00:00:00 UTC | 0 | 0 | 0 |
| Sep 2022 | 2022-09-01 00:00:00 UTC | 2022-10-01 00:00:00 UTC | 0 | 0 | 0 |
| Oct 2022 | 2022-10-01 00:00:00 UTC | 2022-11-01 00:00:00 UTC | 0 | 0 | 0 |
| Nov 2022 | 2022-11-01 00:00:00 UTC | 2022-12-01 00:00:00 UTC | 0 | 0 | 0 |
| Dec 2022 | 2022-12-01 00:00:00 UTC | 2023-01-01 00:00:00 UTC | 0 | 0 | 0 |
| Jan 2023 | 2023-01-01 00:00:00 UTC | 2023-02-01 00:00:00 UTC | 2 | 2 | 0 |
| Feb 2023 | 2023-02-01 00:00:00 UTC | 2023-03-01 00:00:00 UTC | 1 | 1 | 0 |
| Mar 2023 | 2023-03-01 00:00:00 UTC | 2023-04-01 00:00:00 UTC | 3 | 3 | 0 |
| Apr 2023 | 2023-04-01 00:00:00 UTC | 2023-05-01 00:00:00 UTC | 0 | 0 | 0 |
| May 2023 | 2023-05-01 00:00:00 UTC | 2023-06-01 00:00:00 UTC | 1 | 0 | 1 |
| Jun 2023 | 2023-06-01 00:00:00 UTC | 2023-07-01 00:00:00 UTC | 0 | 0 | 0 |
| Jul 2023 | 2023-07-01 00:00:00 UTC | 2023-08-01 00:00:00 UTC | 0 | 0 | 0 |
| Aug 2023 | 2023-08-01 00:00:00 UTC | 2023-09-01 00:00:00 UTC | 2 | 0 | 2 |
| Sep 2023 | 2023-09-01 00:00:00 UTC | 2023-10-01 00:00:00 UTC | 0 | 0 | 0 |
| Oct 2023 | 2023-10-01 00:00:00 UTC | 2023-11-01 00:00:00 UTC | 0 | 0 | 0 |
| Nov 2023 | 2023-11-01 00:00:00 UTC | 2023-12-01 00:00:00 UTC | 1 | 0 | 1 |
| Dec 2023 | 2023-12-01 00:00:00 UTC | 2024-01-01 00:00:00 UTC | 0 | 0 | 0 |
| Jan 2024 | 2024-01-01 00:00:00 UTC | 2024-02-01 00:00:00 UTC | 0 | 0 | 0 |
| Feb 2024 | 2024-02-01 00:00:00 UTC | 2024-03-01 00:00:00 UTC | 0 | 0 | 0 |
| Mar 2024 | 2024-03-01 00:00:00 UTC | 2024-04-01 00:00:00 UTC | 0 | 0 | 0 |
| Apr 2024 | 2024-04-01 00:00:00 UTC | 2024-05-01 00:00:00 UTC | 1 | 1 | 0 |
What Hacker News says
12 sourcesFern (YC W23) | Founding Engineer | New York City | $130k-$160k + 0.5-1.0% equity | Full Time | Open Source | https://buildwithfern.com
REST APIs underpin the internet but are still painful to work with. They are often untyped, unstandardized, and out-of-sync across multiple sources of truth. With Fern, we aim to bring great developer experiences to REST APIs.
Our stack is Next.js + Vercel, Express (Node.js) + FastAPI (Python), Postgres DB + Prisma ORM, and AWS CDK. We're open source: https://www.github.com/fern-api/fern
We closed a Seed this year from top-tier US investors, including Y Combinator, Abhinav Asthana (Postman CEO), Arash Ferdowsi (Dropbox co-founder), and Ian McCrystal (Stripe's Head of Docs).
Learn more: https://www.buildwithfern.com/careers
In Ask HN: Who is hiring? (November 2023)You can recommend it in what context, from openapi (as they claim https://github.com/fern-api/fern#starting-from-openapi ) or from their ... special ... definition schema?
For those wanting less talk, moar code: https://github.com/fern-api/fern-java/blob/0.4.2-rc3/example... -> https://github.com/fern-api/fern-java/blob/0.4.2-rc3/example...
Regrettably, I wasn't able to readily find a matching openapi example, likely cause they really seem to believe their kid-gloves format is the future (or lock in, depending on how bitter one is feeling)
---
confusingly, their repo has a "YCombinator 2023" badge on it that just links to the badge itself. Some Algolia for Launch HN didn't cough up anything, but there was a Show HN I found: https://news.ycombinator.com/item?id=34346428
In tRPC – Build and consume typesafe APIs without schemas or code generation:wave: Hey Mark -- I'm one of the primary contributors to Fern.
+1 to your comment about how needing to support multiple languages results in not being able to leverage certain language specific features. We've tried the best to manage the trade-offs here, but there's a limit to what you can do.
If you have feedback on how we can improve the TypeScript client, feel free to comment here or create an issue on our repo (https://github.com/fern-api/fern)!
In tRPC – Build and consume typesafe APIs without schemas or code generationI'm one of the builders of an open source project (https://buildwithfern.com/docs) to improve API codegen. We built Fern as an alternative to OpenAPI, but of course we're fully compatible with it.
The generators are open source: https://github.com/fern-api/fern
We rewrote the code generators from scratch in the language that they generate code in (e.g., the python generator is written in python). We shied away from templating - it's easier but the generated code feels less human.
Want to talk client library codegen? Join the Fern Discord: https://discord.com/invite/JkkXumPzcG
In OpenAPI v4 (aka Moonwalk) ProposalShow HN: An auto-generated OpenAI Node SDK that's better than the official one
Some part of the OpenAI API can stream events, like the “chat completion” endpoint that’s used by ChatGPT to type out its response. However, the official OpenAI Node SDK doesn’t natively support streaming [1] (though it’s the most requested feature [2]). The recommended approach [3] is kind of a nightmare.
I used Fern [4] to generate an SDK for the OpenAI API. It makes it a lot easier to stream responses! https://github.com/fern-openai/openai-node#streaming
There’s some other niceties of the Fern-generated SDK:
- Endpoints organized by resource, e.g. client.audio.transcribe(...)
- Properties are camelCase to match JS/TS convention (they are snake_case in OpenAI’s SDK)
- The file upload endpoints support Node.js ReadStream, rather than just File
[1] https://github.com/openai/openai-node
[2] https://github.com/openai/openai-node/issues?q=is
Read the rest
Fern: A cross-language alternative to tRPC
5 points · Open discussionShow HN: Stop writing untyped express routes
Hey HN --
We were tired of writing untyped code for our APIs so we started building Fern (https://github.com/fern-api/fern). We just launched our express integration, check out the demo here: https://www.loom.com/share/31f4243c4d824c54938bdc4840fbb8ba.
1 points · Open discussionShow HN: Get notified in Slack for each GitHub star
I wrote a Zap on Zapier to get notified when someone stars your repo. I use it on our open-source repo and it's helpful.
Fern: https://github.com/fern-api/fern
4 points · Open discussionShow HN: Fern, a language for defining REST APIs that compiles into OpenAPI
Hi HN, this is Danny, Deep, and Zach.
We built Fern after our previous ed tech startup failed. We were frustrated with how much time we spent writing “API code” instead of working on the actual product. We tried to use OpenAPI but we were underwhelmed - the generated code wasn’t idiomatic and it still required manual work (custom templates, scripts, manually publishing SDKs to registries).
The Fern compiler takes your API as input and invokes generators that output things like: SDKs, server code, a Postman collection, and an OpenAPI spec.
Some technical highlights about the compiler + generators:
- The compiler (available as a CLI) handles syntactic + semantic validation. It also includes a linter that encodes best practices. If your API Definition compiles, you can have high confidence that the SDKs will generate correctly.
- After all t
Read the rest
he parsing and validation, the compiler outputs an intermediate representation that gets handed off to the generators. This prevents each generator from re-implementing the same parsing and validation logic.
- Each generator is implemented in the language it is targeting - e.g. the Python generators are written in Python, the TypeScript generators are written in TS. It makes the SDKs more idiomatic because every programming language generally has the best tooling/libraries for generating code in itself. We also think it’ll make community involvement + contribution easier.
- The generators can output the code to disk, but also push the code to a Github repo and publish the SDK directly to registries (e.g. npm, Maven).
We are looking for devs to use Fern for API development. If you have any feedback about the process, compiler, or the generated code, we’d love to hear it.
"Plant Store" example: https://github.com/fern-api/plantstore-api
Generated repos:
- https://github.com/fern-api/plantstore-node
- https://github.com/fern-api/plantstore-java
- https://github.com/fern-api/plantstore-postman
- https://github.com/fern-api/plantstore-openapi
Fern keeps your docs and SDKs in sync with your API
1 points · Open discussionFern – An Alternative to OpenAPI
3 points · Open discussion