Viriditas is a focused, discussion-based workshop geared towards coalescing a practical plan for a sustainable settlement on Mars. We will back out approaches and designs that can be implemented in the first crewed missions to Mars circa 2050. We see many parallels between a sustainable Mars and sustainable Earth and will bias discussion toward efforts that support the long-term interests of both planets. We encourage anyone interested in having an in depth and rigorous discussion about actionable biological solutions to ISRU. Please send a brief description of your interests and expertise.