Any code or blog written by Adam is worth spending some time on.
It will be interesting to see how the tasks framework develops and expands. I am sad to see the great Django-Q2 lumped in with the awful Celery though.
It's okay till it's not. Everyone I know who had Celery in production was looking for a substitution (custom or third-party) on a regular basis. Too many moving pieces and nuances (config × logic × backend), too many unresolved problems deep in its core (we've seen some ghosts you can't debug), too much of a codebase to understand or hack. At some point we were able to stabilize it (a bunch of magic tricks and patches) and froze every related piece; it worked well under pressure (thanks, RabbitMQ).
Celery is great and awful at the same time. In particular, because it is many Python folks' first introduction to distributed task processing and all the things that can go wrong with it. Not to mention, debugging can be a nightmare. Some examples:
- your function arguments aren't serializable
- your side effects (e.g. database writes) aren't idempotent
- discovering what backpressure is and that you need it
- losing queued tasks during deployment / non-compatible code changes
There's also some stuff particular to celery's runtime model that makes it incredibly prone to memory leaks and other fun stuff.
Because it’s a seducer. It does what you need to do and you two are happy together. So you shower more tasks on Celery and it becomes cold and non-responsive at random times.
And debugging is a pain in the ass. Most places I’ve been that have it, I’ve tried to sell them on adding Flower to give better insight and everyone thinks that’s a very good idea but there isn’t time because we need to debug these inscrutable Celery issues.
I'm of the opinion that django task apps should only support a single backend. For example, django-rq for redis only. There's too many differences in backends to make a good app that can handle multiple. That said, I've only used celery in production before, and I'm willing to change my mind.
Template partials look good, which is one of the key reasons frameworks like React are as good and popular as they are, because you can reuse small segments of code.
Partialdef inline is the real win. Lets you define parts of a page without needing to place them in another file. Reduces the mental overhead of imagining how the inclusion will look because it’s already there.
The use case is mainly driven by htmx where you will have lots of these partials and the view code renders them as individual responses.
It's just syntactic sugar, making life a bit easier for HTMX users (cf. "htmx was the main motivation for this feature").
I'm using Unpoly and I just render the whole page and let Unpoly swap the content according to the target selectors, so no need for this. Not much difference in perf if you dont generate gigantic pages with heavy header/footer.
It makes me sad when a secondary meaning, which does not even overcome the main meaning in usage, becomes an obstacle for the normal use of a word. It's like seeing a rainbow as a sexualized symbol not fit for children, because it also happens to be used by LGBTQ+ community. (BTW, since you're a Brit: did people stop using the word "fag" to refer to a cigarette?)
I mean, it is sad. But unfortunately that is what happened with "master", "slave", "whitelist", and "blacklist". No reasonable person construed these as offensive or having any implications about the wider world. But there are people in our profession who are determined to take offense where none is given, and unfortunately they got their way.
That didn't stop people from throwing a fit over master-slave terminology in software (having nothing to do with slavery), going so far as to rename long-standing development branch names, as well as put significant effort into removing such terms from the code itself and any documentation.
Any code or blog written by Adam is worth spending some time on.
It will be interesting to see how the tasks framework develops and expands. I am sad to see the great Django-Q2 lumped in with the awful Celery though.
OP here, thanks for the praise!
Yeah, I mentioned Celery due to its popularity, no other reason ;)
You are a great writer - thanks for putting this together!
I’m currently stuck with the tech debt of Celery myself. I understand that! Does Django Tasks support async functions?
Why is celery awful?
> The Many Problems with Celery:
— https://steve.dignam.xyz/2023/05/20/many-problems-with-celer...
> The problems with (Python’s) Celery:
— https://docs.hatchet.run/blog/problems-with-celery
> Dramatiq motivation:
— https://dramatiq.io/motivation.html
Here are some alternatives:
Dramatiq: https://github.com/Bogdanp/dramatiq
RQ: https://github.com/rq/rq
Huey: https://github.com/coleifer/huey
Hatchet: https://github.com/hatchet-dev/hatchet
It's okay till it's not. Everyone I know who had Celery in production was looking for a substitution (custom or third-party) on a regular basis. Too many moving pieces and nuances (config × logic × backend), too many unresolved problems deep in its core (we've seen some ghosts you can't debug), too much of a codebase to understand or hack. At some point we were able to stabilize it (a bunch of magic tricks and patches) and froze every related piece; it worked well under pressure (thanks, RabbitMQ).
Celery is great and awful at the same time. In particular, because it is many Python folks' first introduction to distributed task processing and all the things that can go wrong with it. Not to mention, debugging can be a nightmare. Some examples:
- your function arguments aren't serializable - your side effects (e.g. database writes) aren't idempotent - discovering what backpressure is and that you need it - losing queued tasks during deployment / non-compatible code changes
There's also some stuff particular to celery's runtime model that makes it incredibly prone to memory leaks and other fun stuff.
Honestly, it's a great education.
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Because it’s a seducer. It does what you need to do and you two are happy together. So you shower more tasks on Celery and it becomes cold and non-responsive at random times.
And debugging is a pain in the ass. Most places I’ve been that have it, I’ve tried to sell them on adding Flower to give better insight and everyone thinks that’s a very good idea but there isn’t time because we need to debug these inscrutable Celery issues.
https://flower.readthedocs.io/en/latest/
Computer, load up Celery Man please.
I'm of the opinion that django task apps should only support a single backend. For example, django-rq for redis only. There's too many differences in backends to make a good app that can handle multiple. That said, I've only used celery in production before, and I'm willing to change my mind.
With that logic, the Django orm should only support one database.
Template partials look good, which is one of the key reasons frameworks like React are as good and popular as they are, because you can reuse small segments of code.
The most obvious value here is for HTMX, which requires a lot of partial templates.
Key benefit for reusability and composability in React is IMHO that they don't use templates at all, but everything is a function.
Exactly. There are a few libraries to achieve a similar thing in Python:
* https://htpy.dev/
* https://pypi.org/project/fast_html/
* https://fastht.ml/ (different to above, I think)
* https://github.com/volfpeter/fasthx
Probably others. I strongly prefer this to templating, but I find it makes dyed in the wool Django people squirm.
React allows for encapsulation of state in a reusable component, its more than just templating.
They're a neat design. I started using them on my blog the other day as part of trying out Django 6: https://github.com/simonw/simonwillisonblog/blob/faec3532183...
Amazing that Django didn't have this until 2025
But you could already reuse templates in Django by including them. What am I missing?
Check out the HTMX example in the blog, this helped me better understand how it could be used
https://adamj.eu/tech/2025/12/03/django-whats-new-6.0/#rende...
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Partialdef inline is the real win. Lets you define parts of a page without needing to place them in another file. Reduces the mental overhead of imagining how the inclusion will look because it’s already there.
The use case is mainly driven by htmx where you will have lots of these partials and the view code renders them as individual responses.
It's just syntactic sugar, making life a bit easier for HTMX users (cf. "htmx was the main motivation for this feature").
I'm using Unpoly and I just render the whole page and let Unpoly swap the content according to the target selectors, so no need for this. Not much difference in perf if you dont generate gigantic pages with heavy header/footer.
indeed the vintage templating was a logical bottleneck
How is it different from include? Just less files from my perspective
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There've been a variety of open source attempts at this idea. Is this official one now the best to use, or are the others still compelling?
https://django-cotton.com/ is component-based. I used it a bit, it's nice if you're used to the ways of front-end frameworks, I guess.
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Template Partials and HTMX seems like the Django equivalent of View Components and Stimulus for Rails, which is nice.
Also, good to see first class support for Tasks, among a lot of other niceties!
If I understood correctly, to use Tasks in production right now you need to use this as well:
https://github.com/RealOrangeOne/django-tasks
Is that correct?
More discussion: https://news.ycombinator.com/item?id=46153116
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Well, https://en.wikipedia.org/wiki/Nonce_word
It makes me sad when a secondary meaning, which does not even overcome the main meaning in usage, becomes an obstacle for the normal use of a word. It's like seeing a rainbow as a sexualized symbol not fit for children, because it also happens to be used by LGBTQ+ community. (BTW, since you're a Brit: did people stop using the word "fag" to refer to a cigarette?)
I mean, it is sad. But unfortunately that is what happened with "master", "slave", "whitelist", and "blacklist". No reasonable person construed these as offensive or having any implications about the wider world. But there are people in our profession who are determined to take offense where none is given, and unfortunately they got their way.
2 replies →
We don't need to bring this kind of thing up. We're not school children and most of us are technology professionals, so the meaning is clear.
These guidelines are relevant here:
Eschew flamebait. Avoid generic tangents. Omit internet tropes.
Please don't pick the most provocative thing in an article or post to complain about in the thread. Find something interesting to respond to instead.
Please don't complain about tangential annoyances—e.g. ... name collisions ... . They're too common to be interesting.
https://news.ycombinator.com/newsguidelines.html
American hegemony, and all that.
In the US they spell it as nonze.
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https://en.wikipedia.org/wiki/Context
That didn't stop people from throwing a fit over master-slave terminology in software (having nothing to do with slavery), going so far as to rename long-standing development branch names, as well as put significant effort into removing such terms from the code itself and any documentation.