Fix problems with a web app, then maintain on an on-going basis

We're a small, forward-thinking hospitality business that provides a chores and errand-running service for our customers. We're big on quality and providing the best service that we can. What we're looking for is part-time help to update and maintain our web app which has been created in Ruby Rails. Firstly, there are some minor problems that need fixing now. Secondly, we are looking for on-going reliable maintenance, updates, emergency fixes, and advice in helping us achieve our goals. Thirdly, going forward, we want to make bigger changes, such as making the app quicker, more user-friendly, provide better and more services, and link the app to our other software. The initial project may be 10 hours of work. On-going will likely be 1 hour per week for maintenance and updates. Then the bigger projects of adding more services and linking to other software - time required? To be determined. This position would be on a casual basis working on projects as required. Work will not occur in our office but be from the successful applicant's home. You will need to self-manage your timesheet, timing and progress of each project, and be an excellent communicator. There will be flexibility but you will need to be reliable and finish projects by agreed deadlines.