Languages are easy. But do you think you could jump from systems programming in C to mobile programming on Android “easily”.

I’ve seen people jump from Java to C#. You can see the difference in their coding style, them not taking advantage of the features of the language, reinventing the wheel because they didn’t know there were popular packages that would do it for them, creating horrible inefficient queries and practices using EF etc.

Sure, jumps like that are not as bad as you might think. Style wise the code is often poor, but users don’t really care about the code.

I started with Object Pascal on Mac OS 8/9 which forced you to do a lot of low level tasks like deal with Handles and suffer through a cooperative multithreaded OS. Rewriting the network layer from AppleTalk to TCP/IP was closer to systems programming in C than you might think.

I have also been paid to write C programs, Windows application pre .Net in Visual C++ and post in C# and VB, written Java and C# websites, and most recently Angular SPA’s. Add to that a few random oddities like XSLT.

PS: I even turned down working on Android, but could have made that jump.

The jump is huge. Web development has a completely different model than mobile development. In web development, losing a connection is a failure case. Developing for mobile it is expected. Especially for enterprise apps. Logic is usually distributed, syncing is required, knowing which is the source of truth etc.

This is really an example of hiring someone who has experience and hiring someone who thinks “it’s easy and just like what I did before”.

Then I could get into all of the old netops guys who think AWS is just like what they did on prem and end up costing the company more...

They are different, but I don’t think networking is one of the major differences.

Website backends often have significant dependence on other services that can be down. Further standalone apps can have zero network dependence or a lot. So having written both, and similar code for each, I don’t feel the networking side is all that different.

If anything networking is probably the largest similarly between them.

PS: I did some iOS development in my spare time even worked with some old J2ME, so I assume Android is fairly similar.

>In web development, losing a connection is a failure case.

That's changing with the advent of progressive web apps. It's possible to write web apps now that are robust in the face of network problems, e.g., the web app renders and is functional even without a connection.

I’m not questioning whether you can do it with web technology. But you still have to design it where both your business logic and your data can live on the device and it can queue submitted data until there is a connection available and if multiple people are updating the same record, knowing how to merge the information or knowing which one takes precedence. I’ve even seen cases where the logic depended not on just the record, it depended on knowing which fields were updated by the device when it was disconnected and the prior value of the field to make sure that the user had seen the most recent value before they updated it. If not, someone on the back end had to do a “manual merge conflict resolution” by calling both people.

You frequently encounter similar issues between multiple web servers. Either due to scaling to multiple data centers or when multiple independent services all update the same information. This can get really complex when clients start talking to multiple different services.

> You can see the difference in their coding style, them not taking advantage of the features of the language, reinventing the wheel because they didn’t know there were popular packages that would do it for them, creating horrible inefficient queries and practices using EF etc.

That's why code reviews are a mentoring opportunity. Help your colleague level up.

(Also there should be team dialogue about how to solve some problems more efficiently, I mean, if I was unsure of something I would go and ask colleagues for some guidance, or you would go and do some research on your own)

Now not only do you have a less effective developer who takes time to ramp up, you’re also taking time from senior developers.

I’m not saying this is always the right course and of course this doesn’t scale to larger companies, but my first project at my current company a week in was to develop a feature from scratch which ended up involving coding an API for the front end developers, writing an ETL process that used both Redshift (AWS OLAP database), and MySQL designing the schemas, configuring the AWS resources with CloudFormation, setting up queues, messages, lambdas, dealing with the vendor we were integrating with and learning the business vertical. How much longer would it have taken if instead of already knowing their stack - C# WebAPI, MySQL, and AWS - I came from a Java/Mongo/GCP background?

They needed someone useful now to get a feature out that they wanted to charge customers for.