Development Agency
that excels in delivering
marketing & sales goals

Automation of administrative tasks

Goal

Automation of administrative tasks

Unlocking the potential of organic traffic

Goal

Unlocking the potential of organic traffic

Reducing lead acquisition cost

Goal

Reducing lead acquisition cost

Increasing user engagement

Goal

Increasing user engagement

Growth in conversion rate

Goal

Growth in conversion rate

Trusted by:

Hortex
Swiss Krono
Roche
+

dozens of lesser-known yet
equally remarkable SMEs

We understand your challenges like no one else.
We create digital products that address them.





Results-Driven Technology:

Results-Driven Technology:
Increased page speedHigher user engagementA/B testing of UX solutionsSEO & GEO optimizationReduced bounce rate

Not just functional, but beautiful:

Not just functional, but beautiful:
Boosts conversions and wins industry awardsEngages users effectivelyAligns seamlessly with brand communicationSkillfully leverages brand assets

Built with business understanding:

Built with business understanding:
Fixed-fee model availabilityGDPR complianceWCAG optimizationDemonstrating ROI on investmentExecutive summary for key stakeholders

Such a unique approach—at the intersection of marketing and technology—is possible thanks to the diverse expertise of our group

Web applicationseCommerceMobile applicationsUX/UI designWebsitesCustom software
Marketing strategy and advisoryAdvertising and creative conceptsSocial Media & ContentPerformance marketing & analyticsMedia buyingSEO & GEO optimization

Behind these competencies stand exceptional people. Our group consists of leading experts with over 13 years of market experience.

Michał Strześniewski

Michał Strześniewski

Lead Web Developer

Adam Kanigowski

Adam Kanigowski

Front-end Engineer

Aleksander Kożuchowski-Przybyszewski

Aleksander Kożuchowski-Przybyszewski

Head of Digital Products

500+

digital marketing projects within KERRIS. Communication strategies, creative concepts, and performance campaigns. These projects have given us a deep understanding of marketers' challenges.

120+

web & mobile implementations within 300.codes. From informational websites and engaging applications to advanced, tailor-made eCommerce solutions.

Why do our clients want to work with us?

1/20

300.codes development team, as a part of KERRIS, worked on Agronomist portal implementation. I am happy to admit that 300.codes has fulfilled its obligations with due dillegence, fully implementing the terms of the contract. The work went quickly and with high quality standards. I can recommend 300.codes as a proven and reliable partner.

Katarzyna Wielgosz
Katarzyna Wielgosz
BNP Paribas Bank Polska S.A.

They know what they were doing, were really professional but above all when we were at crucial moments of the project, they showed adaptability and understanding and were able to implement new changes so as to satisfy the Client and meet the highest expectations.

Paweł Oleszczuk
PwC

The team created a great atmosphere, making progress and delivering quality work while having fun along the way. They genuinely enjoy what they do and set a high bar for themselves. They listen closely to their partners and act accordingly, from the proposal stage through to development. Approachable, smart, and with a strong sense of ownership, they handle any obstacles on the road swiftly and effectively.

Klaudia Raczek
deepsense.ai

300.codes, as a part of KERRIS, was responsible for designing and implementing the Bonduelle Master app for professionals. I am pleased to confirm that 300.codes is not just a contractor, but a reliable partner who cares about developing useful, high-quality digital products.

Wioletta Bielecka
Bonduelle Food Service

We were most impressed by 300.codes’ innovative gamification in the LMS, boosting engagement and learning outcomes. Their excellent project management, timely delivery, and responsiveness ensured a smooth execution. Plus, their client-focused approach and proactive communication made the process seamless and highly satisfying.

Monika Szukalak
Global Healthcare Company

300.codes stands out as an impressive software development company due to their technical prowess, customer-centricity, transparency, and commitment to delivering exceptional results. Their unique blend of expertise and values makes them an invaluable and trusted partner for businesses seeking top-tier software development solutions.

Bartek Drozdz
Kuula

They have very professional design service standards, as well as a team of high-class specialists who deserve trust. Working with 300.codes you know that you are in good hands and your project will be delivered to the highest standards. I couldn’t expect more.

Zdjęcie przedstawiające Macieja Karnickiego
Maciej Karnicki Jr.
SWISS KRONO Group

Working with the project manager was satisfying. Projects were always delivered on time, and there was a quick response time in crisis situations. With my hand on my heart, I can recommend this person for coordinating projects in large companies.

Zdjęcie przedstawiające Mateusza Abramczyka
Mateusz Abramczyk
CEDC International

300.codes is a really engaged partner that I can count on in business and technical areas. It is really rare on the market and some kind of their USP – 300.codes is not only a contractor and technical vendor, it is also your business partner.

Piotr Sztenkiel
MyGift

300.codes’ work helped the client redefine their company’s strategic goals by refreshing their visual identity. The team strictly adhered to the established timeline and budget, making for a seamless workflow. They impressed with their professionalism and receptiveness to client input.

Dorota Nieroda
Obsessive

What is really impressive about 300.codes is that they really care about your business. 300.codes model rely on business approach and I can confirm it is visible during cooperation. You can find a lot of contractors on the market but if you want to find a partner, 300.codes is certainly the right choice.

Jakub Łączkowski
Pozamiatane

What sets 300.codes apart is their ability to seamlessly integrate design and development. Moreover, their dedication to understanding our brand and translating it into the digital space was commendable. Commitment to our project and their genuine interest in our success made it feel like they were an extension of our team rather than an agency.

Zdjęcie przedstawiające Kacpra Raszkiewicza
Kacper Raszkiewicz
Epinote

Definitely demonstrated enthusiasm, professionalism, and flexibility. From the beginning, 300.codes was determined to deliver a result that meets our expectations. That is not easy to observe on the market.

marcin_adamczyk
Marcin Adamczyk
BNP Paribas Bank Polska S.A.

Working with 300.codes means having a committed partner. I am pleased to admit, the 300.codes team are professionals, focusing on close dialogue and achieving business goals.

Marcin Owsiany
SWISS KRONO

What is really special about 300.codes is their boutique service. They put a lot of emphasis on understanding business goals and working according to them. Moreover, I can assure you that their customer service is top-notch.

Kamila Dryjańska
SWPS University

The integration project was a success. 300.codes was able to meet the client’s demands promptly and effectively. The team showcased their superb professionalism as they heavily focused on transparency and clear communications between the two parties.

Adam Czeczuk
Think Beyond

300.codes was very focused on efficient communication and process transparency. That allowed us to have a great workflow between both teams. In everyday contact we used emails, Slack and Jira. Their communication is consistent with the actual business model. 300.codes is a listener that cares for your business first, which is rare on the market.

Rafał Grudowski
Grupa Insight

The client is delighted with the new site, describing it as more premium-looking. 300.codes is a reliable partner — they deliver quality services in a timely and budget-friendly manner. The team is also dedicated to each task, and they communicate regularly to ensure both sides are always in sync.

Marcin Szychowski
Veoli Botanica

300.codes emphasizes its boutique approach to software delivery by focusing on close personal interactions, transparency, business care, and a proactive approach. I have to admit that they honestly stick to the communicated values.

tomasz gierat
Tomasz Gierat
SWISS KRONO

300.codes provided us a great IT support, especially in the range of front-end development works. Cooperating with 300.codes in a long distance deserves special attention. Our company is based in Singapore, however there haven’t been any communication problems despite different timezones or business cultures. We firmly believe 300.codes is more than capable to run complex digital projects for companies located anywhere in the world. We would highly recommend them.

Paweł Kuźnicki
Capital Match (Singapore)

We showcase our quality through numerous awards and valuable partnerships.

Award-Winning Team:

Recognized Business:

Partnerships:

What do we specialize in?

eCommerce web development services

Mobile applications development

Web applications developers

Web design and development services

Technological Expertise

Front-end

  • React.js
  • Vue.js

Back-end

  • Symfony
  • Cake
  • Laravel
  • Zend
  • Python

eCommerce

  • WooCommerce
  • Sylius

Mobile

  • Native Script
  • Quasar

CMS

  • WordPress

Others

  • Three.js

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