--- title: "SEO & Growth Hacking - José DA COSTA" description: "SEO and growth hacking, in my view, is the **cross-functional skill at the seam between marketing and engineering**. It covers technical SEO (Core Web Vitals, structured markup, sitemap, international" locale: "en" canonical: "https://portfolio.josedacosta.info/en/skills/seo-growth-hacking" source: "https://portfolio.josedacosta.info/en/skills/seo-growth-hacking.md" html_source: "https://portfolio.josedacosta.info/en/skills/seo-growth-hacking" author: "José DA COSTA" type: "skill" slug: "seo-growth-hacking" generated_at: "2026-04-26T21:14:36.427Z" --- # SEO & Growth Hacking Icon: 📈 ## My definition SEO and growth hacking, in my view, is the **cross-functional skill at the seam between marketing and engineering**. It covers technical SEO (Core Web Vitals, structured markup, sitemap, internationalisation), content SEO, link-building, SEM, SERP analysis, and the full growth toolbox (instrumentation, A/B testing, acquisition funnel). It is not a commercial add-on: an OSS published without an organic acquisition strategy never pays back the writing cadence. ### Context I run this competency in **2 complementary modes**. **Audit**: site diagnosis in less than 4 hours, 90-day action plan with measurable impact, technical baseline laid before content. **Run**: editorial calendar, community-driven link-building, paid when relevant. The skill was **forged at Celiane** (1999-2007) where the entire business model rested on the SEO of a network of **260 multilingual sites** monetised through affiliation, and kept sharp afterwards through ACCENSEO engagements and the published OSS (gradient-generator-css, tailwindcss-obfuscator). ### Relevance In 2026, SEO is going through its **biggest shift since the rise of Google** with the emergence of **GEO (Generative Engine Optimisation)**: optimising to surface **as a citation in ChatGPT, Perplexity, Claude, and Google AI Overviews answers**, no longer just to rank in the traditional SERP. AI-referred sessions **jumped 527% in five months in 2025**, and Search Engine Land details the mechanics in [Generative engine optimization (GEO): How to win AI mentions](https://searchengineland.com/what-is-generative-engine-optimization-geo-444418). The CTO or founder who misses the GEO 2026 transition silently loses a growing share of qualified traffic. ## My evidence ### From the Celiane SEO business model to the OSS gradient generator **Context:** My first real SEO learning was **Celiane**, the company I started at **18 in 1999**. For **9 years** the business model rested entirely on the **organic traffic** of a network of **260 multilingual sites** (15 languages, 5 countries), monetised through affiliate marketing. When Google penalised content farms in 2006-2007 the venture wound down - but the SEO discipline acquired across those years stuck. More recently, in January 2026, I wanted to verify that the muscle was still active on a developer OSS: the **CSS Gradient Generator** (Next.js 16 + React 19 + ~980 presets + AI generation through OpenAI). **Action:** I applied the same discipline as back then, modernised. On the technical side, **Core Web Vitals baseline** (strict TypeScript, optimised Tailwind 4, Next.js prerendering), **structured markup** SoftwareApplication + Article, auto-generated **sitemap**, clean internationalisation. On the content side, **semantic clusters** around CSS gradient search intents (linear, radial, conic, mesh) and an **editorial calendar** on color spaces (OKLab, OKLCH). On the distribution side, **community-driven link-building** through open-source publication and developer-focused channels. On Celiane back then, it was the same playbook - just with a weekly cadence and manual SERP tracking on Google + MSN + Voilà.fr. **Result:** On Celiane, **sustainable organic traffic across several years**, **TOP 10 France** for Carpediem affiliates, **PageRank 5-6/10** on the main sites, **roughly 500 K euros of cumulative net profit**. On the CSS Gradient Generator, **measurable organic acquisition** within the first week of release, fast indexation of the preset pages. **Value added:** 20-6 years after my first Celiane sites, SEO remains a **reproducible muscle** - the principles (intent-driven, technical baseline, structured content, link-building) survived every search-engine evolution. It is a background competency I now replay automatically on every ACCENSEO product I publish, and it differentiates me from pure-tech CTOs who must lean on a growth manager to even exist on the engine. ### Pushing tailwindcss-obfuscator into the SERP and into LLM answers **Context:** When I shipped **tailwindcss-obfuscator** to npm in late 2025, I knew technical quality was not enough: in such a competitive niche (first Tailwind v4-compatible package), if nobody found it, the package would die in obscurity. The 2025-2026 SEO novelty was **GEO** (Generative Engine Optimisation): showing up in ChatGPT, Claude, Perplexity answers when a developer asks a technical question - now as important as ranking on Google. **Action:** I built the **SEO + GEO** strategy in parallel with the code. Classic SEO: **on-page optimised product page** (title, meta, **SoftwareApplication schema**), **long-form** content on Babel AST + PostCSS to rank on precise technical intents ("how to obfuscate Tailwind v4 classes", "Tailwind v4 mangle plugin"), **VitePress** for indexable documentation, clean **sitemap**. GEO: structuring explanations by clear intents, detailed code examples, explicit comparisons with the incumbent. I test **every quarter** the appearance in LLM answers on 5 key intents. **Result:** **External team adoption** within the first weeks after release, **organic mentions** in several tech newsletters, top positions on the specific queries (Tailwind v4 + obfuscation), surfacing in LLM answers on the clearest search intents. **Value added:** From this package I built a **reproducible SEO/GEO framework** that I now replay on every ACCENSEO OSS release. It is my differentiator against pure-tech competitors: an OSS without SEO/GEO strategy does not pay back the writing cadence, and that is exactly what makes a **content-led / product-led growth** strategy thinkable on the next CTO scale-up role without depending solely on a paid budget. ## My self-critique ### Mastery level Level **Confirmed**. Production exposure rests on two registers: founder SEO at [Celiane](/en/journey/cto-founder-directeur-technique-celiane), where organic traffic stood in for the entire business model for 9 years, and recent OSS growth SEO on gradient-generator-css and tailwindcss-obfuscator. Solid mastery on technical SEO (Core Web Vitals, structured markup, sitemap, internationalisation), correct on semantic strategy and community-driven link-building. What still needs strengthening: **GEO** (Generative Engine Optimisation) in sustained practice, and large-scale paid SEM. ### Importance in my profile High-leverage complement to Strategic Vision. It closes the gap between the technical decision and the acquisition metric: an OSS shipped without an SEO/GEO strategy never pays back the writing cadence. For a B2B SaaS scale-up CTO role, it is what makes a *content-led / product-led growth* strategy possible without depending solely on a paid budget. Not a primary axis, a multiplier. ### Acquisition speed **Self-taught learning** kicked off at **18 (1999)**, no theoretical training. 9 years of Celiane reverse-engineering Google, MSN and Voilà.fr in parallel of running the 260-site network - this competency was forged in the field, not in a certification. ### Advice (for myself and others) To myself: stay close to GEO developments in 2026, test every quarter the appearance in LLM answers (Perplexity, ChatGPT, Claude). To others: - do not wait for content to set the **technical baseline** (Core Web Vitals, URL structure, sitemap) - invest in **authorship and proven expertise** (E-E-A-T) rather than keyword stuffing - measure in **attributed revenue**, not raw visitors ## My evolution in this skill ### Role in my professional project SEO and growth are **what turns an ACCENSEO product into organic revenue**. In the 24-month plan, they fund the first acquisition phase of a new B2B SaaS without depending solely on a paid budget, and they make the published OSS tools (gradient-generator-css, tailwindcss-obfuscator) profitable in developer attention. Without them, every new product starts from zero. ### Mid-term target level Not a Senior bump axis. the goal is to **stay audit-grade**: diagnose a site in less than 4 hours and propose a 90-day action plan with measurable impact. The main effort goes to the **GEO extension** (Generative Engine Optimization), the most moving terrain of 2026 SEO. ### Current training ACCENSEO customer engagements as continuous training, application on the published OSS tools (gradient-generator-css, tailwindcss-obfuscator). Monthly follow of Google Search Console and Bing Webmaster Tools evolutions. ### Future training Formal **GEO** certification as soon as a recognized training emerges (HubSpot, Ahrefs, Semrush are close). Advanced Content Marketing training (Animalz / [Marketing Examples](https://marketingexamples.com/)) targeted 2026 if the content axis becomes a priority. Interactive version with navigation: https://portfolio.josedacosta.info/en/skills/seo-growth-hacking