add fosdem 2025 talk and update video links

ydb/docs/en/core/public-materials/_includes/conferences/2023/HighLoad.md

@@ -6,7 +6,7 @@ Implementing a distributed database with strong consistency isn’t difficult; e
 
 [{{ team.ivanov.name }}]({{ team.ivanov.profile }}) ({{ team.ivanov.position }}) discussed the architecture of YDB, demonstrated its high performance through benchmark results, and compared YDB with its competitors.
 
-@[YouTube](https://youtu.be/iMjq96GQTHQ?si=moMbI3Je90s3zY60)
+@[YouTube](https://youtu.be/84t_6jV2m5E?si=z3YrrRaCvifSo6JN)
 
 The presentation will be of interest to developers of high-load systems and developers of platforms for various purposes.
 

ydb/docs/en/core/public-materials/_includes/conferences/2024/TechInternals.md

@@ -12,7 +12,7 @@ We'll conclude our talk by presenting performance results from the TPC-C benchma
 
 [{{ team.ivanov.name }}]({{ team.ivanov.profile }}) ({{ team.ivanov.position }}) discussed best high-performance benchmarking practices and some pitfalls found during TPC-C implementation, then demonstrated TPC-C results of PostgreSQL, CockroachDB, and YDB.
 
-@[YouTube](https://youtu.be/LlqfqzPtLD0?si=YYDcXkUZFsLJRJEY)
+@[YouTube](https://youtu.be/PYkVo8ApuAE?si=1HQFzWp3UGgNGFAP)
 
 The presentation will be of interest to developers of high-load systems and developers of platforms for various purposes.
 

ydb/docs/en/core/public-materials/_includes/conferences/2024/coscup.md

@@ -4,7 +4,7 @@
 
 PostgreSQL is an implementation of SQL standard with one of the most vibrant ecosystems around it. To leverage all the tools and libraries that already know how to work with PostgreSQL, emerging database management systems that bring something new to the market need to learn how to mimic PostgreSQL. In this talk at [COSCUP 2024](https://coscup.org/2024/en/session/XZ98GN) [{{ team.blinkov.name }}]({{ team.blinkov.profile }}) ({{ team.blinkov.position }}) explores possible approaches to this and related trade-offs, as well as reasoning why YDB chose a unique approach to bring serializable consistency and seamless scalability to the PostgreSQL ecosystem.
 
-{% include [no_video](../../no_video.md) %}
+@[YouTube](https://youtu.be/84t_6jV2m5E?si=z3YrrRaCvifSo6JN)
 
 The presentation is suitable for people interested in trade-offs during implementation of PostgreSQL-compatible DBMS.
 

ydb/docs/en/core/public-materials/_includes/conferences/2025/fosdem.md

@@ -0,0 +1,15 @@
+## Designing YDB: Constructing a Distributed cloud-native DBMS for OLTP and OLAP from the Ground Up {#2023-conf-hl-serbia-scale}
+
+{% include notitle [database_internals_tag](../../tags.md#database_internals) %}
+
+Distributed systems offer multiple advantages: they are built to be fault-tolerant and reliable, can scale almost infinitely, provide low latency in geo-distributed scenarios, and, finally, are geeky and fun to explore. YDB is an open-source distributed SQL database that has been running in production for years. Some installations include thousands of servers storing petabytes of data. To provide these capabilities, any distributed DBMS must achieve consistency and consensus while tolerating unreliable networks, faulty hardware, and the absence of a global clock.
+
+In this session, we will provide a gentle introduction to the problems, challenges, and fallacies of distributed computing, explaining why sharded systems like Citus are not always ACID-compliant and how they differ from truly distributed systems. Then, we will dive deep into the design decisions made by YDB to address these difficulties and outline YDB's architecture layer by layer—from bare metal disks and distributed storage to OLTP and OLAP functionalities. Finally, we will briefly compare our approach with that of Calvin, which originally inspired YDB, and Spanner.
+
+[{{ team.ivanov.name }}]({{ team.ivanov.profile }}) ({{ team.ivanov.position }}) discussed the architecture of YDB, focusing on building a unified platform for fault-tolerant and reliable OLTP and OLAP processing.
+
+@[YouTube](https://youtu.be/fMR6zQVchgE?si=ru-xdaY8p1MpLus4)
+
+The presentation will be of interest to developers of high-load systems and platform developers for various purposes.
+
+[Slides](https://presentations.ydb.tech/2025/en/fosdem/designing_ydb/presentation.pdf)

ydb/docs/en/core/public-materials/videos.md

@@ -7,6 +7,11 @@ Video recordings from conferences and webinars. The materials are divided by cat
 
 {% list tabs %}
 
+- 2025
+
+  {% include [FOSDEM](./_includes/conferences/2025/fosdem.md) %}
+
+
 - 2024
 
   {% include [IndiaFOSS](./_includes/conferences/2024/indiafoss.md) %}