Apogee Architectural Lighting is a local company based in Long Island. They are mainly known for their work on fixtures for MTA, however they are a full operational shop in terms of architectural lighting. We took a look at their Silhouette fixture. It is a linear LED fixture with no visible diodes that can be either surface mounted or recessed. The unique thing about the fixture is that it is all field cuttable in 2" increments including the extrusion and the lens. The extrusion can even be cut at an angle for custom installations. They do not have a mud-in flange, but you can install it as a millwork installation.
They partner up with New Mat and other materials on a lot of their fixtures and can do custom installations ranging from back-lit surfaces to unique back-lit luminaires. For the back-lit fixtures, they will typically use LED boards from other manufacturers, however if the fixture requires it, they can make their own boards to fit. With their recessed back-lit fixtures, they can either do trimmed or trimless. They usually only will need 2-3" of depth but it will depend on the material you are lighting.
Their website does not feature all they are capable of doing so it is best to reach out to them with an idea and see if they can do it. All of their fabrication is done in house and they thrive off of custom work. They have multiple extrusions to offer including several coves. A great thing about Apogee is that most of their fixtures can come with an emergency battery if required.