Helping founders evolve their brand as fast as their product

Illustration of three golden-yellow lines.

vision -> credibility -> growth through GTM strategy & thought leadership

  • Back Market logo with black background and white text
  • StackOne logo with a stylized cube icon and the text 'StackOne' in white on a black background.
  • Logo for Otta, a job search and employment platform, with a circular icon and stylized text.
  • Clue logo with a geometric symbol on the left and the word 'Clue' on the right, on a black background.
  • Logo for Core Angels featuring a stylized microscope as the letter 'O' in 'Core,' with the text 'ANGELS' underneath.
  • Blissgrowth logo with a stylized 'b' in a script font on a black background with white text.
  • Here We Flo logo on a black background with white cursive text.
  • Juniper logo with a stylized pink and white icon of three leaves and the word 'juniper' in lowercase white text on a black background.
  • The word 'beam' written in lowercase white letters against a black background, with a white underline beneath the word.

Our Services

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    Go to Market Strategy and Execution

    We help you research and define your market, sharpen your story and build a GTM motion that converts.

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    Founder and Executive Thought Leadership

    Translate your product and industry expertise into content that moves your prospects through the funnel, faster. 

  • A white funnel icon with arrows pointing downward on a red background.

    Full-Funnel Growth Execution

    We plug in as your fractional CMO, driving both strategic growth and execution at half the price of a full-time hire.

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    Events, PR and Earned Media

    We get you in front of the right audience, at the right time, with the right message through targeted channels.

Unlock Growth Through Founder-Led Marketing

Build trust and turn your founder story into scalable demand.

We’re your founding extension

Formed in the start-up trenches, we've lived the late nights, the pivots and the pressures of raising capital and delivering efficient growth fast. We're grounded in rigour, sharpened by discipline and flexible by nature. We slot in seamlessly to your team, handling your brand’s trust, visibility and momentum so you can stay focused on building.

We move fast, think sharp, and collaborate deeply, every step of the way. 

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Founder & Fractional Head of Marketing

ex-Otta, Here We Flo

Diandra Dumitru

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Fractional Marketing & Growth Manager

ex-Juniper, BlackRock

Camilla Guida

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Fractional Marketing & Growth Manager

ex-Planes, Idean UK

Imogen Lees

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How we help you succeed

Founder-Led Marketing

We help you turn your product insights and industry expertise into a marketing engine across Linkedin, podcasts, events, conferences and everything in-between. So you build authentic trust that accelerates sales cycles, attracts talent and wows investors. One playbook, built to last as your ambitions scale.

Full-Funnel Go-to-Market

We connect every awareness, consideration and conversion touch-point to one measurable pipeline: crafting messaging, wiring martech, launching experiments and tracking success that can your board can see in weeks. So growth compounds long before you’ve built a full team. 

  • “Citadelle has been an extension of our marketing team for nearly a year now, supporting us in telling a highly technical story to a complex prospect and customer base across the entire funnel. Diandra serves as our Head of Marketing and has quickly become a valuable resource for the business, collaborating effectively across our GTM and Product functions. She has recently supported us through our $20M Series A and has helped deliver over 500% growth on key LinkedIn channels, which have become a reliable source of leads.”

    Romain Sestier,

    CEO and Co-Founder at StackOne

  • We’ve been working with Citadelle on an expansive B2B2C Go-to-Market strategy for a new Product: from designing the market and stakeholder research, to developing the channel strategy and executing on key marketing channels, Diandra and Camilla have been extremely diligent, detailed and showed domain expertise from the very beginning. Their attention to detail and care for our mission and vision is inspiring and we’re glad to have been introduced at the ideal time!”

    Balint Veres,

    Chief Finance Officer at Clue

  • Camila brings a deeply thoughtful and strategic mindset to her work. She approached every challenge with a clear sense of purpose, and was methodical in the way she developed and implemented marketing strategies that aligned with our clinical goals. Her ability to understand complex healthcare topics and translate them into clear, engaging messaging was invaluable — particularly in the context of our preventative health and fertility services. She consistently was proactive in finding ways marketing could amplify our impact without compromising on integrity or accuracy. Her collaborative nature, combined with her clarity of thought, made her a real asset across functions.

    Stephanie Pryor,

    Clinical Services Lead at Juniper

  • “Diandra came in to support us while we recruited a full time brand and content lead. She was an absolute godsend, quickly grasping our challenges, sector and internal processes. She slotted right in. I appreciated her calm structured approach and the ideas she brought to the table. We worked together on an influencer campaign, a brand activation event and she led our LinkedIn strategy with great results. I highly recommend Diandra for anyone looking for someone who’s both strategic and operational - an extension of your marketing team!”

    Holly Coxell,

    Head of Marketing at London Women’s Clinic

How can we help? 

Every start-up is different. Whether you need strategic guidance or tactical execution, we're here to help you discover your untapped growth potential.

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