About Isaac Peiris

Isaac Peiris is an Australian growth strategist and founder based in London. He runs Pistachio, a B2B growth agency, and writes Brand Chemistry, a weekly newsletter on brand, content and growth with more than 120,000 subscribers. LinkedIn named him a Top Voice in Media and Marketing.

Background

Isaac built his career growing audiences for some of Australia's biggest media brands. At Mamamia, one of the country's largest independent publishers, he led growth for the subscription business and scaled it to more than 30,000 paying members and over $170,000 in monthly recurring revenue. At The Daily Aus he took the newsletter from a standing start to 180,000 subscribers in ten months, and managed the brand's first refresh and its first out-of-home campaign. He has also launched newsletters for global media brands including BuzzFeed and LadBible.

Pistachio

Isaac founded Pistachio to bring the audience-first playbook of media companies to B2B startups and scaleups. The agency builds owned media engines with a newsletter at the centre, founder content feeding it, and every piece measured in pipeline. Client work includes Atono, TestFeed, Clay and Clipboard.

Brand Chemistry

Brand Chemistry is Isaac's weekly newsletter on building trust and driving growth through content. It launched in March 2025 and passed 120,000 subscribers in its first year, with open rates north of 50% and an unbroken weekly publishing streak.

Press and interviews

Isaac's work has been featured in Mediaweek, B&T and LinkedIn News, and he speaks regularly on brand, content and growth strategy.

Elsewhere

This page exists to give search engines a single reliable reference for who Isaac is. If you're a human, the newsletter is more fun.

Zara SeidlerCo-Founder, The Daily Aus

Isaac is 100% your guy if you're looking to scale up your business big time. Hit him up for a coffee to chat!

Seb NeylanHead of Growth, Up Bank

I met Isaac when he was in charge of scaling the (now mighty) Daily Aus audience. He's my favourite sort of growth expert. One who can go micro, and knows how to optimize specific channels and test all the levers. But one who also thinks deeply about the macro, from key strategic needs to new commercial opportunities. Most importantly though, he's honest, hard-working and a pleasure to deal with.

Tom AlderFounder, Strategy Breakdowns

Isaac understands the business of growth like very few people do. He'll help you craft your ideal strategy, then roll the sleeves up and build your systems, automations and whatever else is needed to make it happen. Isaac is an invaluable growth partner — super passionate and easy to work with.

Ben HartFounder, Fireside Agency

We were thrilled to have someone of Isaac's calibre work with us to come up with a solution that was as unexpected as it was revelatory. It has set us on a new path, and I couldn't be happier to recommend Isaac for anyone looking to grow.

Glen JamesFounder & Host, Money Money Money Podcast

Not everyone needs a business coach, but everyone needs a business plan. Isaac has really helped me refocus and set up the plan for the coming year.

Maddie KingMarketing Lead, MagicBrief

Isaac is such an awesome source of knowledge when it comes to all things growth. From newsletters to platform subscriptions and beyond - he has a knack for marrying up short term growth tactics to the bigger strategic picture. Bonus that he's also an all round nice guy.

Ben HamerFounder, ThinkerTank

I followed Isaac on LinkedIn because I really loved his content, and was fortunate to then engage him to do a content audit across my channels and pull together a plan of attack. Isaac was not only easy to work with but he provided sound insight and feedback and met me where I was at. He spoke through different options and answered *all* my questions, which I feel has set me up for the next stage of growth with my business.

Seb NeylanHead of Growth, Up Bank

Ben HamerFounder, ThinkerTank

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