<h1 id="api-compatability">API Compatability<a aria-hidden="true" class="anchor-heading icon-link" href="#api-compatability"></a></h1>
<p>The need to maintain backward and forward compatibility appears in many <a href="/notes/vutujFFWxQu6TshWVuMpI">distributed</a> systems</p>
<ul>
<li><em>Backward compatibility</em> is making new code compatible with existing data. </li>
<li><em>Forward compatibility</em> is making existing code compatible with new data.</li>
</ul>
<p>Backward compatibility is straightforward. It’s the ability to open old documents in new versions of the program.</p>
<p>Forward compatibility, the ability to open documents in formats invented in the future, is rarer. We can see forward compatibility in web browsers, which are written so the features added to HTML won’t break the ability to render new sites in old browsers.</p>
<p>The publisher of an API must balance their desire to make changes against their customers' reluctance to change something that works for them.</p>
<ul>
<li>The result is strong pressure to preserve backward compatibility over time, often across many versions.</li>
</ul>
<p>An API publisher can intuit that an endpoint can respond with additional data, trusting existing clients to ignore it, but not require additional data in requests, because existing clients won’t know to send it. </p>
<p>Stripe <a href="https://stripe.com/blog/api-versioning">solved this problem</a> by building a middleware system through which all requests and responses to its API travel. It translates between the latest version of the Stripe system and the API version that the client is using. As a result, Stripe developers don't have to worry as much about nuances with old API versions, since the middleware ensures the old version will be converted to comply with the latest version. When Stripe developers want to create a new API version, they just need to add a new stack to the middleware.
<img src="/assets/images/2022-03-18-13-01-30.png"></p>
<h2 id="tools">Tools<a aria-hidden="true" class="anchor-heading icon-link" href="#tools"></a></h2>
<ul>
<li><a href="https://github.com/inkandswitch/cambria-project">Cambria</a>
<ul>
<li>helps us achieve campatability between schema versions— You specify (in YAML or JSON) a lens, which specifies a data transformation.</li>
<li>takes lessons from Stripe's middleware approach to compatability (described above)</li>
<li><a href="https://www.inkandswitch.com/cambria/">Intro and overview of Cambria</a></li>
</ul>
</li>
</ul>
<h2 id="e-resources">E Resources<a aria-hidden="true" class="anchor-heading icon-link" href="#e-resources"></a></h2>
<p><a href="https://www.inkandswitch.com/cambria/">https://www.inkandswitch.com/cambria/</a></p>
<hr>
<strong>Backlinks</strong>
<ul>
<li><a href="/notes/WQoMTf6VXBaxCgksXAVsj">Kafka</a></li>
</ul>

API Compatability

tech

This Dendron vault of tech knowledge is organized according to domains and their sub-domains, along with specific implementation of those domains.

For instance, Git itself is a domain. Sub-domains of Git would include topics like `commit`,
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The goal of the wiki is to present data in a manner that is from the perspective
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from a specific domain. For instance, if a user wants to use postgres functions
and hasn't done them in a while, they should be able to query
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that have been employed in the past.

This wiki has been written with myself in mind. While learning each of these
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insights as they arose. I have refrained from capturing information that I
considered obvious or otherwise non-beneficial to my own understanding.

As a result, I have allowed myself to use potentially arcane concepts to help
explain others. For example, in my note on [[unit testing|testing.method.unit]],
I have made reference to the [[microservices|general.arch.microservice]] note.
The ability to analogize between different concepts captured in different notes
allows an opportunity to build strong generalized understandings. Given that
you'd have to understand microservices to be able to draw that same parallel
that I've already drawn, these links won't work for everyone. Since these notes
are written for myself, I have been fine with taking these liberties and leaning
on them heavily.

What I hope to gain from this wiki is the ability to step away from any
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whatever my goals are within a short period of time. Of course this is all
vague sounding, and really depends on the domain along with the ends I am
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To achieve this, the system should be steadfast to:
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This Dendron notebook is the sister vault to the general [Second Brain](https://tech.kyletycholiz.com).

## Tags
Throughout the garden, I have made use of tags, which give semantic meaning to the pieces of information.

- `ex.` - Denotes an *example* of the preceding piece of information
- `spec:` - Specifies that the preceding information has some degree of *speculation* to it, and may not be 100% factual. Ideally this gets clarified over time as my understanding develops. I try to go back after I have better understood the topic and clear out the notes of `spec:` tags
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## Resources
### UE (Unexamined) Resources
Often, I come across sources of information that I believe to be high-quality. They may be recommendations or found in some other way. No matter their origin, I may be in a position where I don't have the time to fully examine them (and properly extract notes), or I may not require the information at that moment in time. In cases like these, I will add reference to a section of the note called **UE Resources**. The idea is that in the future when I am ready to examine them, I have a list of resources that I can start with. This is an alternative strategy to compiling browser bookmarks, which I've found can quickly become untenable.

### E (Examined) Resources
Once a resource has been thoroughly examined and has been mined for notes, it will be moved from *UE Resources* to *E Resources*. This is to indicate that (in my own estimation), there is nothing more to be gained from the resource that is not already in the note.

### Resources
This heading is for inexhaustible resources. 
- A prime example would be a quality website that continually posts articles.  - Another example would be a tool, such as software that measures frequencies in a room to help acoustically treat it.
