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Ask HN: Are there any openly available software architecture documents?

by passenger on 1/10/20, 3:45 PM with 49 comments

• by davalapar on 1/11/20, 1:56 AM

  There are bunch of them, really.

  But for general structure, using your end-user's user experience path (from start to end) as a guide and avoiding buzzwords as much as you can usually help. Think of Stripe's documentation, you want something as easily digestible as that.

  - Software Design Patterns: https://en.wikipedia.org/wiki/Software_design_pattern

  - Azure Application Architecture Guide: https://docs.microsoft.com/en-us/azure/architecture/guide/

  - Azure Cloud Design Patterns: https://docs.microsoft.com/en-us/azure/architecture/patterns...

  - Azure Architecture Framework: https://docs.microsoft.com/en-us/azure/architecture/framewor...

  - Azure Cloud Adoption Framework: https://docs.microsoft.com/en-us/azure/cloud-adoption-framew...

  - Cloud Computing Patterns: https://www.cloudcomputingpatterns.org/

  - Microservice Architecture Patterns: https://microservices.io/patterns/index.html

  - Amazon's Builders Library: https://aws.amazon.com/builders-library/

• by claudiulodro on 1/10/20, 6:52 PM

  There are dozens at the Architecture of Open Source Applications ebook/site: http://aosabook.org/en/index.html

  As someone who only really gets exposure to web tech, it was fascinating how other types of software is architected, too.

• by Ididntdothis on 1/10/20, 5:14 PM

  Don’t do it like me and overthink it. Just write down all your thoughts informally. Make diagrams by hand. Only once you have most content then think about formatting and structure. A lot of people produce nicely looking docs without much content. I much prefer a bunch of simple notes that describe the thought process

• by blowski on 1/10/20, 4:43 PM

  C4 is pretty easy to learn, Arc42 has some sample documents that are very useful. They complement each other.

  https://c4model.com/

  https://arc42.org/documentation/

  PRINCE 2 documents also come with a 'decision log', if you want something in a formal template.

• by deepaksurti on 1/10/20, 4:39 PM

  The book `Documenting Software Architectures ...` [1] can help.

  [2] and [3] list a few example documents for Software Architectures, you can google further and find some more.

  I think reading through a few sample documents and based on the expectations at your current job, you can derive the necessary doc.

  [1] https://www.amazon.com/Documenting-Software-Architectures-Be...

  [2] https://projects.cecs.pdx.edu/attachments/download/3146/Soft...

  [3] https://www.voa.va.gov/DocumentView.aspx?DocumentID=188

• by zeko1195 on 1/10/20, 4:34 PM

  AWS has nice whitepapers on their software architecture.

  https://aws.amazon.com/whitepapers/?whitepapers-main.sort-by...

• by doctor_eval on 1/11/20, 8:02 AM

  I’m a huge fan of code as design [1], so I tend to do my architecture thinking at a high level - the objects and interactions between systems - and then write clear and simple code which expresses my intention. To this end, if the code is clear then it doesn’t need to be documented heavily.

  I’m also a big fan of DDD [2] and use his “box and line” drawings all the time. There are loads of resources for DDD but I’ve linked to the book, which is awesome. DDD has great concepts like Context Boundaries and Ubiquitous Language which may simplify the documentation process.

  It’s easy to think of architecture too abstractly or in terms of frameworks or other complexifying concepts, but simple is good, and that’s true from top to bottom.

  [1] http://www.developerdotstar.com/mag/articles/reeves_design_m...

  [2] https://www.goodreads.com/book/show/179133.Domain_Driven_Des...

• by EliRivers on 1/11/20, 11:43 AM

  I'd also have to document why certain decisions were taken.

  Yes please. So much this. With evidence, please, so that the decisions can be revisited in the future and changed when they no longer apply. Every day I open another source file on a system that was built over a decade by a rotating cast of mostly first job software engineers without adequate mentorship and (I wish I was making this up) having their C++ code reviewed by a C programmer who gave them comments such as "just turn all these functions into one-line macros", and someone who appeared to be mainlining late-nineties OOP hype like it was going out of fashion and needed to get it all on the page before someone beat him to death with an old Vic 20.

  Every day we stare at it and ask ourselves why. Why was it done like this? Was there a good reason back then? Does that reason still exist? If I rewrite it to remove all this horror, will something else break? Even, oh God, even "What is this actually meant to do?" I can see what it does do. What it does do makes no sense. Did it ever make sense?

  Even the occasional comment like "cheeky hack for performance" is often more hindrance than help when a quick test shows it actually makes performance worse. Did it ever improve things? Did the hardware change underneath it such that it no longer helps? Did other code change such that it no longer applies?

  Anyway, where this was going is that a decision recorded without evidence or even the factors considered might as well have been a coin toss to the software archaeologist having to maintain it in a decade's time. If the decisions and reasoning aren't recorded, you're forcing someone to attempt to reverse-engineer your state of mind, and that's an expensive and impossible job.

• by weitzj on 1/10/20, 6:08 PM

  Plantuml for drawing pictures together with the C4 Plantuml Plugin is helpful. i.e. you make high level overviews of your architecture and then „zoom in“

  For decisions a table with some explainatory comments why you have decided to use this one thing and which alternatives you have considered and why those did not make it, helps. You can look up ADRs. (Decision Records)

• by jupp0r on 1/10/20, 5:52 PM

  There is the excellent Architecture of Open Source Applications book, which is available online for free at http://aosabook.org/en/index.html

  It contains architecture overviews of many open source projects.

• by qznc on 1/10/20, 6:42 PM

  Our design decision documents have essentially four sections: Problem description, solution options, comparison of the options, and decision. I find it helpful to clearly distinguish what is part of the problem and what part of the solution. The size of the sections varies a lot.

  Meta information could be: Status, stakeholders, decision-makers, and rollout description. It also often has links to meeting protocols and tickets.

• by kejaed on 1/10/20, 6:02 PM

  This might initially look to be be a little too specific for military / aerospace, but it can act as a good guideline for a table of contents and examples of what might go in each section.

  https://github.com/VCTLabs/MIL-STD-498/raw/master/MIL-STD-49...

  The US Military came up with their own standard for systems and software development (MIL-STD-498), which as evolved into IEEE and ISO standards. The nice thing about the US Military's standards is that they came with Data Item Descriptions (DIDs) that specify exactly what goes in each document.

• by mindcrime on 1/11/20, 7:41 AM

  I am a fan of Phillipe Krutchen's[1] "4+1" model[2], or variants thereof. The book Software Systems Architecture: Working With Stakeholders Using Viewpoints and Perspectives[3] by Eoin Woods and Nick Rozanski is a really good overview of the overall mechanism.

  Also, while this bit is probably overkill for your current situation, you may find value down the road in looking at some of the various "architecture frameworks"[4] and reference models that are out there. Things like TOGAF[5], DODAF[6], MODAF[7], TRAK[8], etc.

  In any case, always remember the words of the immortal Bruce Lee:

  “Absorb what is useful, discard what is useless and add what is specifically your own”.

  [1]: https://en.wikipedia.org/wiki/Philippe_Kruchten

  [2]: https://en.wikipedia.org/wiki/4%2B1_architectural_view_model

  [3]: https://www.amazon.com/Software-Systems-Architecture-Stakeho...

  [4]: https://en.wikipedia.org/wiki/Enterprise_architecture_framew...

  [5]: https://en.wikipedia.org/wiki/The_Open_Group_Architecture_Fr...

  [6]: https://en.wikipedia.org/wiki/Department_of_Defense_Architec...

  [7]: https://en.wikipedia.org/wiki/MODAF

  [8]: https://en.wikipedia.org/wiki/TRAK

• by cgarvis on 1/11/20, 2:20 AM

  I found the 4+1 architecture docs very helpful when working with a recent client. https://en.m.wikipedia.org/wiki/4%2B1_architectural_view_mod.... What I like about it is that it separates the architecture into four views each for a different audience

• by lanstin on 1/10/20, 8:45 PM

  Most important thing to convey is the conceptual framework used and assumptions made to simplify things. e.g. "We will fix problems only by altering the base image, not the build system." "We will not change to 64-bit build as a part of this change." The sort of thing so that if someone really internalizes the perspective, they will be able to decide all the details on their own. Also a basic picture is always very popular. The details should be in git someway or another, but being able to use the details quickly is the job of the overview. I find it useful to document common change workflows ('To add another type of processor, add the class name to this map in this file, provide a jar implementing that class here, and add a new ID to the enum here.')

• by bvogelzang on 1/10/20, 7:07 PM

  I've found this to be a pretty great resource: https://github.com/joelparkerhenderson/architecture_decision...

• by NicoJuicy on 1/10/20, 7:31 PM

  ADR is made for this

  https://github.com/joelparkerhenderson/architecture_decision...

  There are multiple variants. Simple or detailed.

• by myrloc on 1/10/20, 5:00 PM

  PlantUML is useful for diagramming anything from sequences to system architecture to state machines. It's also widely supported in many modern text editors like emacs and VSCode. PlantUML components for AWS are widely available [1]. You may find RealWorldPlantUML a good place to start looking for examples [2].

  [1] https://github.com/milo-minderbinder/AWS-PlantUML [2] https://real-world-plantuml.com/

• by Geee on 1/11/20, 10:33 AM

  I've used the C4 model to draw an overall system architecture (container level + external systems). https://c4model.com

• by markmiro on 1/11/20, 6:28 PM

  I think it's worth looking at it like another product that you produce. I like to imagine someone seeing my code for the first time and trying to make sense of it.

  Architecture: this is often documented with some kind of diagram. I personally find them to be unhelpful.

  Flow: I'm guessing people aren't familiar with your UI. The best way to document would be to record a video, but that might be a little extra. I would make a powerpoint doc with screenshots to show the common flows.

  For me, it kinda looks like this:

  - Assume expertise in the individual technologies you've used

  - If you picked the tech, then write why you did, and link to resources to learn more about it

  - Write down which general constraints I placed on myself that might not be common. EX: naming patterns, cyclomatic complexity, using a functional approach, or being more point-free in a language where it's not common, choices around duplicate code

  - Make a nested list of the folder structure and describe what each folder is for (even if it feels obvious), and describe how the different parts interact with each other. The questions to answer are: what are the high-level dependencies between dirs? Are there any cyclical dependencies?

  - Find the knots (especially complex parts of the codebase) and make sure they're documented properly

• by nullandvoid on 1/10/20, 6:02 PM

  I agonized over the best way to do this stuff for a while also and the best framework I've used so far is the C4 model (as mentioned elsewhere).

  For documenting decisions on architecture this should be done as you go really but better late than never :). Using adr ( architecture decision records ) text / md files would be my approach. They will typically be kept alongside the code and source controlled

• by jankar on 1/11/20, 10:39 AM

  A little known, but powerful notation for description and documentation of architecture of Information Processing Systems is FMC http://www.fmc-modeling.org/ This site features a link to the Apache Modeling Project where a now outdated version of httpd was documented using this methodology.

• by Naac on 1/10/20, 5:25 PM

  I would also look at "The Architecture Of Open Source Applications", although it might be more detail than you're looking for.

• by bhamp0 on 1/10/20, 5:45 PM

  Archi software to draw Archimate diagrams.

• by harshulpandav on 1/11/20, 4:32 AM

  Making use of colors in architectural diagrams really add depth to the information. Often applications involve internal and external (out of scope) components. Using common colors for each group of components really helps in the readability.

• by TruffleLabs on 1/10/20, 5:14 PM

  If you only have a few weeks then there might not be any good results: you have to spend time learning the framework and also provide the relevant/ required info.

  It is an opportunity to learn and apply it forward to your new job.

• by mister_hn on 1/10/20, 9:48 PM

  GitLab has all of their docs online..I guess you can dig into them for inspiration

• by luxuryballs on 1/11/20, 6:29 AM

  Tell them the code is so good it documents itself.

• by mitchtbaum on 1/11/20, 2:38 AM

  import: English

  import: Diagram

  ok: Community

  see: https://www.drupal.org/project/project_module?f%5B2%5D=im_vi...

• by exabrial on 1/10/20, 5:06 PM

  Yikes, if you haven't been doing this as you go you've severely messed it up.