To be a successful computer programmer, both for freelance programming service or programming services, one needs to have a specific set of skills. Here are some of the key skills required for a computer programmer:

1. Technical skills: A programmer needs to have a strong understanding of the programming languages they work with, as well as an understanding of computer systems and architecture.
2. Problem-solving: A programmer needs to be able to analyze a problem, break it down into smaller parts, and find a solution.
3. Attention to detail : A programmer needs to be meticulous and pay close attention to detail, as small errors in code can cause significant problems.
4. Communication skills: A programmer needs to be able to effectively communicate with clients, team members, and other stakeholders.
5. Time management: A programmer needs to be able to manage their time effectively and prioritize tasks to meet deadlines.
6. Adaptability: Technology is constantly changing, and a programmer needs to be able to adapt to new technologies and programming languages as needed.
7. Passion for technology: Finally, a programmer needs to have a genuine passion for technology and a desire to continue learning and improving their skills.

In conclusion, these are some of the key skills required for a successful computer programmer, whether it's a full-time or freelance programming service. It's important for a programmer to continue developing these skills and expanding their knowledge of programming languages and technologies to remain competitive in this field.