Product design & engineering agency

Design, launch and evolve
your digital products.

We design and develop your web and mobile applications, from product discovery to production. Entrust your project to our agency or embed our product, design and engineering expertise in your team.

Discuss your needsExplore our work
Product design and development·Embedded expertise·Audit and takeover

References

Engineering delivered for software companies, startups and SMEs.

Taking over live applications, building products, cloud architecture and AI integration. The names below represent our project experience.

BlisterrParktoMeduzViblyReavoxFantasy AlleyFred n' SoSur les traces d'UlariusKaptn

Studio Bidibou becomes Black Tide Studio.

Same team, new identity. Studio Bidibou SARL remains the legal entity operating Black Tide Studio.

Read our story

Two ways to work together

Build a product, or strengthen the team behind it.

Entrust us with your product or move your team forward with our expertise. We work according to your needs and organisation.

01

Product design and development

Your needs become a product designed, launched and supported.

Our agency takes care of product discovery, UX/UI design, architecture, development, launch and evolution. Entrust us with the whole journey or bring us in at the stage you need.

Explore product development

02

Expertise embedded in your team

Your organisation needs an additional skill or capacity.

We contribute within your product, design and engineering teams: discovery and prioritisation, UX/UI, mobile, web and backend, cloud and AI integration. Your priorities, standards and routines.

Explore embedded expertise

Audit and takeover

Move your existing application forward

A slow, fragile product or one left without a team: assess the existing system, prioritise risks and take over where it makes sense.

Explore audit and takeover

Two projects in detail

The need, our role, the decisions and the outcome.

Two representative engagements: taking over and evolving a live product, and auditing and stabilising an application before a fixed deadline.

Blisterr

Product evolution

Live auction platform · Ongoing since 2026

Business and user need
Sell collectibles live, with an auction that remains clear and reliable for both buyers and sellers throughout the broadcast. The product was already live and needed to keep running.
Our role
Take over the existing Flutter application and backend, then evolve them without service interruption.
Product and technical decisions
A progressive Strangler Fig migration instead of a rewrite: the application moves to hooks and Riverpod in phases while remaining live, and the backend moves from MongoDB to PostgreSQL 17 table by table. Streaming combines LL-HLS and LiveKit on infrastructure provisioned on demand.
Outcome
In production and under continuous iteration. Viewer latency stays below three seconds and the cost per viewer-hour is approximately six times lower than an all-WebRTC architecture. Backend migration is ongoing.
Read the full case

Parkto

Audit and takeover

B2C mobile application · One-month engagement

Business and user need
A B2C application opening to the public on a fixed date, with sign-up, payment and its core functionality reliable on launch day.
Our role
Take over the product after the original team’s engagement ended, four weeks before launch.
Product and technical decisions
Map the debt before fixing it, then decide what to stabilise and what to retain. Three critical journeys were isolated and secured with integration tests and Sentry monitoring; debt elsewhere was documented rather than hidden.
Outcome
Launched on the planned date, with stable critical journeys, documented technical debt and a remediation plan handed to the client. This was the schedule for this engagement, not a standard delivery time.
Read the full case
View all our work

Capabilities

What we bring together in one engagement.

These capabilities combine according to the product, your team and the chosen engagement model.

Discovery and prioritisation

Translate business needs and usage into a scope: priority journeys, value, effort and risk trade-offs, and success criteria. Deliverables: a discovery brief, prioritised scope and an appropriate roadmap.

Discovery · prioritisation · roadmap

UX/UI design and prototyping

Journeys, prototypes, interfaces and design rules. We work through usage decisions with you and deliver designs, components and specifications the development team can use.

Flows · prototypes · design system

UX/UI design

Web and mobile engineering

iOS and Android applications in Flutter or native Swift and Kotlin, web platforms, APIs and integrations with your existing systems.

Flutter · Swift · Kotlin · Next.js · NestJS

Product design and development

Cloud and operations

AWS architectures, PostgreSQL databases, automated deployments and monitoring. The scope described reflects what we operate in production.

AWS · PostgreSQL · Docker · Terraform

Cloud architecture and DevOps

Applied AI

Integrate language models into an existing product or process: feasibility, data access, quality, cost, latency and human oversight.

OpenAI · Anthropic · Mistral

AI and LLM integration

The technologies listed are used in the engagements presented in our portfolio.

Explore our services

Product method

Understand, prioritise, design, launch, evolve.

Deliverables and working arrangements are tailored to each engagement. Entrust us with the whole journey or join at the stage you need.

  1. 01 — Understand

    Understand the need, users and context.

    What the product needs to enable, for whom, in what context, and what remains an assumption. We start with the problem to solve, not a list of features.

  2. 02 — Prioritise

    Agree the scope before building.

    Priority journeys, expected value, effort and risk. Discovery produces a priced scope, success criteria and documented decisions with alternatives.

  3. 03 — Design and validate

    Design the journeys, then test the assumptions.

    Journeys, prototypes, interfaces and design rules. Assumptions are tested with users where the agreed scope provides for it.

  4. 04 — Build and launch

    Build, test and release.

    Architecture, development, code review, testing and continuous integration, followed by acceptance criteria, monitoring and operational preparation.

  5. 05 — Observe and evolve

    Observe real usage and decide what comes next.

    User feedback, available observations, prioritisation of future increments, maintenance and handover. Ongoing support is defined in the agreement.

Continuity

What stays with you after the engagement.

What we put in place during the engagement so your team stays in control. Support and handover arrangements are specified in the proposal.

Access to code and environments

Source code, repositories and environment access are with you during the engagement, not just at the end. You do not need to request a delivery to see the product’s progress.

Operational documentation

Architecture diagrams, data models, API contracts and deployment procedures are written during the engagement and versioned with the code. These are the materials another team needs to take over.

Priority reviews and handover

Priorities are reviewed at agreed intervals: what has shipped, what remains and what has changed. Handover to your team or another supplier is prepared throughout the engagement.

Frequently asked questions

Budget, collaboration and working arrangements.

Answers to the questions that come up before a first conversation.

What budget should we plan for a Black Tide engagement?

It depends on the service. A product is priced after discovery; our public reference ranges are €12–25k excluding VAT for a prototype, €35–70k for an MVP and €80–160k for an evolving product. Embedded expertise is priced by intervention days, based on our public €750 daily rate excluding VAT. In both cases, scope and risk determine the quote.

Product delivery or embedded expertise: how do we choose?

Entrust us with a project when you want to delegate its design and delivery. Choose embedded expertise to complement a team already steering its product.

How long does mobile application development take?

Timing depends on scope, integrations and the expected level of finish. Discovery helps define realistic increments and a delivery schedule.

Native or cross-platform: which should we choose?

We choose according to usage, platform constraints and available skills. Flutter shares one codebase; native development addresses certain specific needs.

How do you work with our team, remotely or on site?

We work remotely from Île d’Oléron, with travel depending on the engagement. We agree tools, responsibilities and checkpoints together.

Do we need a written specification?

No. Tell us about the need, users and constraints. Discovery turns those into a workable scope.

Next step

Let’s discuss your needs.

Describe the context, your team and your deadline. We’ll discuss feasibility and a suitable engagement model, or point you elsewhere if it falls outside our scope.

Discuss your needsEmail us
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