HackerReposA FIELD GUIDE TO OPEN SOURCE
ProSponsor the shelf♧ 0
← Back to top all-time
sebbekarlsson
fjb
C2021–2021
sebbekarlsson / fjb

fjb

fast javascript bundler :package:

2Distinct people
3Mentions
0Explicit recommenders
109GitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

fast javascript bundler :package:

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, 3:56:07 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 month3 dated mentions

Observed mentions: 2021-02-06 21:29:14 UTC to 2021-09-21 19:30:44 UTC.

012021-02-01 00:00:00 UTC to 2021-03-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 commentsFeb 20212021-03-01 00:00:00 UTC to 2021-04-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2021-04-01 00:00:00 UTC to 2021-05-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2021-05-01 00:00:00 UTC to 2021-06-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 commentsMay 20212021-06-01 00:00:00 UTC to 2021-07-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2021-07-01 00:00:00 UTC to 2021-08-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2021-08-01 00:00:00 UTC to 2021-09-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2021-09-01 00:00:00 UTC to 2021-10-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 commentsSep 2021

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
Feb 20212021-02-01 00:00:00 UTC2021-03-01 00:00:00 UTC101
Mar 20212021-03-01 00:00:00 UTC2021-04-01 00:00:00 UTC000
Apr 20212021-04-01 00:00:00 UTC2021-05-01 00:00:00 UTC000
May 20212021-05-01 00:00:00 UTC2021-06-01 00:00:00 UTC000
Jun 20212021-06-01 00:00:00 UTC2021-07-01 00:00:00 UTC000
Jul 20212021-07-01 00:00:00 UTC2021-08-01 00:00:00 UTC000
Aug 20212021-08-01 00:00:00 UTC2021-09-01 00:00:00 UTC101
Sep 20212021-09-01 00:00:00 UTC2021-10-01 00:00:00 UTC101

What Hacker News says

3 sources
esbuild is the current darling leading the pack, but there are also various other projects in the space (swc[0] is written in Rust, fjb[1] is written in C, bun[2] is written in zig, leveraging JavascriptCore's engine). The most significant performance-oriented effort in this space still leveraging JS that I know of is kataw[3], and while that's quite fast compared to babel, it's still within an order of magnitude from babel. Kataw itself is a CST-based implementation that was created to outperform seafox (a AST-based parser by the same developer), which itself is an iteration over several other perf-oriented parser projects. Babel gained popularity due to the crazy amount of churn in grammar over the past few years, but more and more I think the dust is settling, and flexibility is no longer the name of the game, making an AST-based imple
Read the rest
mentation less appealing. The Rome team must be feeling the heat if the data structure design choices are being informed by performance. I highly doubt someone will be able to compete in performance using a JS implementation in today's landscape. [0] https://github.com/swc-project/swc [1] https://github.com/sebbekarlsson/fjb [2] https://bun.sh/ [3] https://github.com/kataw/kataw
In Rome will be written in Rust
Nice write-up. I have explored different repo strategies quite a bit myself in the course of a few efforts that I've been involved with. On one, we originally had a monolythic framework and everything the article said about cons is pretty spot on. However, I'll qualify by saying that I think the problems come less because of the nature of monolyths in general and more because of lack of experience with modular design. We wrote a new framework from scratch using a monorepo approach, with separate packages via Lerna. The problem here was tooling. Dependent builds were not supported and I've had to delete node_modules more times than I'd ever cared to count. The article talks about some github specific problems (namely, the issues list being a hodge-podge of every disparate package). We tried zenhub, it works ok, but it's a hack and it kinda
Read the rest
shows. I've seen other projects organize things via tags. Ultimately it comes down to what the team is willing to put up with. We eventually broke the monorepo out into multi-repos, and while that solved the problem of managing issues, now the problem was that publishing packages + cross-package dependencies meant that development was slower (especially with code reviews, blocking CI tests, etc). Back to a monorepo using Rush.js (and later Bazel). Rush had similar limitations as Lerna (in particular, no support for dependent tests) and we ditched it soon afterwards. Bazel has a lot of features, but it takes some investment to get the most out of it. I wrote a tool to wrap over it[0] and setup things to meet our requirements. We tried the "multi-monorepo" approach at one point (really, this is just git submodules), and didn't get very good results. The commands that you need to run are draconian and having to remember to sync things manually all the time is prone to errors. What's worse is that since you're dealing with physically separate repos, you're back to not having good ways to do atomic integration tests across package boundaries. To be fair, I've seen projects use the submodules approach[1] and it could work depending on how stable your APIs are, but for corporate requirements, where things are always in flux, it didn't work out well. Which brings me to another effort I was involved with more recently: moving all our multi-repo services into a monorepo. The main rationale here is somewhat related to another reason submodules don't really fly: there's a ton of packages being used, a lot of stakeholders with various degrees of commit frequency, and reconciling security updates with version drift is a b*tch. For this effort we also invested into using Bazel. One of the strengths of this tool is how you can specify dependent tasks, for example "if I touch X file, only run the tests that are relevant". This is a big deal, because at 600+ packages, a full CI run consumes dozens of hours worth of compute time and we see several dozens commits a day. The problem with monorepos comes largely from the sheer scale: bumping something to the next major version requires codemods, and there's always someone doing some crazy thing you never anticipated. With that said, monorepos are not a panacea. A project from a sibling team is a components library and it uses a single repo approach. This means a single version to manage for the entire set of components. You may object that things are getting bumped even when they don't need to, but it turns out this is actually very well received by consumers, because it's far easier to upgrade than having to figure out the changelog of dozens of separate packages. I used a single repo monolyth-but-actually-modular setup for my OSS project[2] and that has worked well for me, for similar reasons: people appreciate curation, and since we want to avoid willy-nilly breaking changes, a single all-emcompassing version scheme encourages development to work towards stability rather than features-for-features-sake. My takeaway is that multi-repos cause a lot of headaches both for framework authorship and for service development, that single repos can be a great poor-mans choice for framework authors, and monorepos - with the appropriate amount of investment in tooling - have good multiplicative potential for complex project clusters. YMMV. [0] https://github.com/uber-web/jazelle [1] https://github.com/sebbekarlsson/fjb/tree/master/external [2] https://mithril.js.org/
In From a Single Repo, to Multi-Repos, to Monorepo, to Multi-Monorepo

MAKE YOURSELF AT HOME

A few shortcuts

/
Search the collection
?
Open this guide
Esc
Close dialogs and navigation

Your saved repositories and interests stay in this browser.