When you are out on your own, or given more responsibility in regards to the way you approach software development tasks. At junior level you would mostly be working under others and contributing to projects through tasks assigned and delegated to you by a technical lead or more senior members of the team. At mid-level you would be involved much more in making critical decisions and given more autonomy in regards to the way you approach and solve software projects. You will be involved in decision making and have responsibility for being more autonomous than a junior level developer. You would be moving towards being a developer that gets things done regardless of the fact that decisions and pre-requisite steps are missing from the process when the task falls in your lap. Mid level developers use their skills to get things done by making critical decisions by themselves.

overuse of singleton is considered an antipattern...

Avoid global objects at all costs, don't be tempted to start using static classes, variables and methods either to mimic the use of global objects in code. Read about the perils of static classes, methods and variables here . Read about the code smell static cling here . Spend some time acquainting yourself with Object Orientated Programming best practices and Code smells. Global variables and objects are a code smell. What you need to think about is designing services in your application with Dependency Injection in mind so that you can manage the lifetime of these services effectively. Typically you would need to develop your application to be loosely coupled so that you can utilise Dependency Injection and a Dependency Injection Container to manage the lifetime of the services the application provides. This would normally involve a class with a method call called the composition root that composes all the objects in the application. The Dependency Injection Container if you choose to use one can be configured to deal with all the dependencies in the application and manage their lifetimes. Example Lifetime scopes are Singleton(Return a single instance of an object every time it needs to be used), Transient and others that take into consideration concurrency. If a Dependency Injection Container is too much complexity for your application you can compose and manage object lifecycles yourself in code. There should be no need for global variables or objects in an Object Orientated Application. To save you time and effort start thinking regarding the best practices of OOP from now on in the way you write and structure code: +SOLID principles +Clean Code and Architecture - Robert C Martin +Acquaint yourself with and learn about Code Smells and how to avoid them.

Depends on how much you will need to use these in your day to day responsibilities. I would say that if this is something that you will need to be using daily and requires deep understanding of then yes you should know the ins and outs of the graph algorithms. All in all knowing and understanding Algorithms and computer science best practices from the ground up will improve your skills as a developer. Algorithmic design involves complex problem solving and application of logic to achieve a goal. Learning and understanding algorithms thus improve and adds to your analytical repertoire as a Software developer/programmer.

All of the above in my eyes!

Hi, @maruru a good place to start learning about User Experience and user interface design is through Steve Krug's excellent and seminal books on Software Usability Design: Don't Make Me Think, Revisited: A Common Sense Approach to Web Usability (Voices That Matter) Rocket Surgery Made Easy: The Do-It-Yourself Guide to Finding and Fixing Usability Problems (Voices That Matter) I think it's important to realise that User Interface design doesn't have to be a mysterious activity. Realise that User Interfaces need to be people-centric, thus you design user interfaces and user experiences for people. Start from the perspective of your audience and how your audience use software, the best UI designs are self evident, simple and follow good conventions.

Interfaces are a critical part of Dependency Injection and will allow you to Mock the functionality defined by the interfaces during Unit testing. I completely disagree with the idea that they are redundant if you think one class will ever implement them. I have numerous applications where I have defined an interface and only have one class implementation of said interface. The power of interfaces lies in the ability to define abstractions in our programs and create dependancies on said abstractions to promote loose coupling. Interfaces aren't just used to achieve polymorphism. They allow for flexibility in your code...

Try established productivity techniques like Pomodoro, they feature working intensely and in a focused manner with breaks after each focused stretch...

As a rule I always run DML sql statements within a Transaction using BEGIN TRAN when Creating, Updating & especially Deleting data to make sure that any changes can be easily rolled back. Using DELETE should never be an issue as long as you are careful and allow for roll back and even backing up data in case something goes wrong.

I have to say that I haven't been good with this but am planning on developing this going forward. The majority of my learning initiatives have been on the job during working hours through tasks that I have been assigned. The best way tot learn is by doing, throwing yourself into a task and solving the problem of completing said task. I would say that I am lucky to have a computer science degree under my belt as it meant that I was taught from first principles. Key things that you should spend time on if you don't have a computer science degree: Data Structures and Algorithms: Core module that can and will develop proficiency as a developer. There are great books on this like the Addison-Wesley book available on Amazon. This subject is language agnostic and I would call it hard computer science in that it involves the design and creation of algorithms and understanding of data structures that underpin the fundamentals of programming. I can't express how important this subject is, even-though today many algorithms are encapsulated within programming languages and frameworks a strong and good grasp of data structures and algorithms is crucial in regards to being a good developer/programmer. Subjects like algorithmic time complexity are a must learn. I have started using Plural Sight for my learning and development goals. I am also taking it in bite size steps(1/2 hours a few days a week) and am planning on developing a number of my own personal projects. A good place to start is focus your learning and development initiatives on the fundamentals and to technologies that are relevant to you and what you are currently doing. You should consider starting personal projects and hosting these on something like Git Hub. Employers are impressed by physical evidence and examples of the way you are passionate about the industry. Collaborating in communities and using Git Hub to host projects is an excellent way to do this. In my experience I have been given advice that becoming an expert in all languages and frameworks is unrealistic. You are better off starting with exposure to a particular language or technology then building from that foundation. Exposure and experience in different technologies is better than trying and failing to be an expert in one. Its about being pragmatic and focused because the field is vast. I was also told when I started working that SQL and database skills are critical to ALL Technical professionals especially developers.