Jessamy has nearly twenty years’ experience developing and delivering voluntary sector partnerships. Across the past eight years she built and delivered a grant strategy at Treebeard Trust, identifying, managing and monitoring a large portfolio of partnerships focused on violence against women and girls, refugees and asylum seekers, criminal justice and the environment. She also supported the Trust's emerging impact investment activity. Prior to this, Jessamy spent ten years as fundraiser in youth mental health and education charities working across trust, corporate and statutory partnerships, most recently at Teach First where she led the Corporate Partnerships team to secure and deliver major strategic corporate partnerships and corporate volunteering programmes.

Joining Hestia's board and Finance and Fundraising sub-committee in November 2024, Jessamy is also a Trustee of her local youth club in Suffolk and sits on the Project Forum committee of Lighthouse Pedagogy Trust.