A mid-level developer, also known as a "senior" in some organizations, requires more technical knowledge than a junior developer. In addition to the technical skills required for a junior developer, a mid-level developer should also be familiar with:
- Advanced language features.
- Performance evaluation of code (i.e., not pulling one million records from a database into memory).
- Conscious usage of programming patterns (i.e., "I could use a singleton here instead of a normal class").
- Limited knowledge about commonly used third-party libraries and services, such as Redis, Elasticsearch, Kafka, etc.
- More knowledge about the software ecosystem and general scope.
- A focus on error prevention rather than error handling.
- Understanding the importance of error messages.
Learning capabilities are improved, and acquiring new skills takes less time. Soft skills are also further improved from the junior level:
- Better forethought about possible solutions.
- Improved ability to estimate the difficulty of assigned tasks.
- Improved ability to identify gaps in requirements.
- Better balance in asking for help.
In short, a mid-level developer can handle tasks independently, begin to look into other areas of development, and think about the bigger picture.
To reiterate, mid-level or senior developers require a higher level of technical knowledge and experience than junior developers. In addition to the technical skills required for junior developers, mid-level developers must be familiar with advanced language features, conscious usage of programming patterns, performance evaluation of code, and limited knowledge about commonly used third-party libraries and services. They must also have a deeper understanding of the software ecosystem and be able to anticipate and prevent errors.
Mid-level developers also have improved learning capabilities and soft skills compared to junior developers. They have better forethought about possible solutions, improved ability to estimate the difficulty of assigned tasks, and can identify gaps in requirements. They have a better balance in asking for help and can handle tasks independently while thinking about the bigger picture.
While junior developers require guidance and supervision in their day-to-day tasks, mid-level developers can handle tasks independently and have a deeper understanding of the software development process. With improved technical skills, learning capabilities, and soft skills, mid-level developers can anticipate and prevent errors, evaluate code performance, and use programming patterns more consciously. Therefore, it is essential for companies to have a clear understanding of the skills and knowledge required for each seniority level to ensure they hire the right candidates for the job and provide the necessary training to help them grow in their careers.