Marketing that evolves as fast as the product it's selling.

AI-Native Marketing & GTM support for Seed to Series A.

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  • 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.
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  • Clue logo with a geometric symbol on the left and the word 'Clue' on the right, on a black background.
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  • 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.
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Our bread and butter

  • AI-Native Marketing Systems

    We build AI systems that do the production work of a full marketing team, so you get senior output without the headcount.

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    Go to Market Strategy and Execution

    We refine your positioning, your messaging and the go-to-market motion to prove it, then execute with you every step.

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    Founder and Executive-Led Growth

    We turn your expertise into content and visibility that accelerate deals, attract talent and convince investors.

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    Embedded Marketing Leadership

    We lead your marketing end-to-end, with senior judgment at the table from the first campaign to your next raise.

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 amazing products.

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

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Marketing & GTM

ex-Otta, Here We Flo

Diandra Dumitru

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Operations & Investment

ex-Juniper, BlackRock

Camilla Guida

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Community & Agency Marketing

ex-Planes, Idean UK

Imogen Lees

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The marketing engine behind your next raise

AI-native production with senior judgment on every call that matters.

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How we help you succeed

Founder-Led Marketing

Positioning, founder-led narrative and board-level strategy stay with operators who've taken startups from Seed through Series A. You get the speed of software with the judgment of a senior hire.

Marketing that ships weekly

Positioning, founder-led narrative and board-level strategy stay with operators who've taken startups from Seed through Series A. You get the speed of software with the judgment of a senior hire.

  • A woman with curly dark hair, glasses, earrings, and a striped top smiling indoors.

    “Citadelle has been an extension of our marketing team for a year and a half, supporting us in telling a highly technical story to a complex prospect and customer base across the entire funnel. Diandra served as our Head of Marketing and quickly became a valuable resource for the business, collaborating effectively across our GTM and Product functions. She also supported us through our $20M Series A and 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

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    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

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    Camilla 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

  • A man with curly dark hair, glasses, and a beard, wearing a dark green sweater, sitting indoors in front of a white wall with a plant visible in the background.

    “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

  • "Working with Citadelle has been transformative for our marketing efforts. More than plugging resource gaps, they built a complete program for us. Over the last few months they audited our LinkedIn presence and designed thought leadership strategies for our executives that translated complex HR Tech themes into accessible insights. They led the creative and logistics around an important campaign, ran podcasts and webinars, producing content plans, registration pages and follow‑up sequences, and made sure our event calendar – from in-person dinners to industry conferences – had a clear narrative and outreach plan. We even developed a new ICP together so we could communicate effectively with the right stakeholders, and the team went above and beyond to introduce us to relevant contacts. By the end of the engagement we had a repeatable marketing engine, better brand recognition and a toolkit we can run with. Citadelle’s strategic thinking and hands‑on execution have given us confidence in our next stage of growth."

    Howard Flint, CEO of AMP Strategists

How can we help? 

Every startup 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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