The project is located in the China-Singapore Tianjin Eco-City, which is part of a large residential area. With a building area of 12000 ㎡, the project serves as the community business center. It includes small community commerce, apartments and supporting services. The tightly constrained site is located in the triangular area in the Northwest corner of the residential are. The main urban road adjacent to the North side of the project will be the most trafficked road. The light rail station overhead is separated from the road on the West side of the project. As a necessary stop for community residents on their way home from the light rail station, diverse services are provided. Therefore, we put forward the concept of "micro TOD" and "composite community" to build the project into the core place of community public activities. The building should be at least four floors, due to the constrained area and the required commercial and supporting services. This constraint is a great challenge for the commercial operations. Therefore we spread the building volume over the site to make the building as low as possible while conforming to the triangular site. Using the courtyard and inner street, we form an enclosed commercial and public space, which is conducive to a commercial atmosphere. A multi-level platform improves the value of the second and third floors. The light rail station hall floor is connected to the commercial 3rd level by an air corridor. This makes the project a “micro TOD” and introduces a large number of people to the courtyard to improve commercial vitality. The apartment section should be placed above the business and arranged as close to the street corner as possible to strive for better visibility and natural lighting from the South. The business area is separated from the residential area to avoid interference between the two. The roof is built into a circular roof three-dimensional garden providing a rich activity space for the community. On the facade of the building, the bottom layer creates a dynamic business atmosphere through staggered red brick blocks. The upper sections forms an overall rhythmic image with large and small folded perforated aluminum plates. Arc-shaped metal aluminum plates form a splendid architectural expression that varies per the changing lighting conditions throughout the day. The building has built a three-dimensional business street, a dynamic courtyard, a light rail connection layer, and a three-dimensional roof garden. These sections accommodate more public activity spaces, upgrading ordinary community commerce into a composite community center.