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- Kafka: Siege 31 waves · 7 free
- Redis: Voxel Defense 54 lessons · 6 free
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| Free free account Play | Full access €39 once Unlock | |
|---|---|---|
| Kafka: Siege | ||
01The LogHow partitions bound a consumer group, what the ISR, acks and min.insync.replicas promise about a write, when a commit turns a crash into lost or repeated work, and how batching and keys decide where load lands. The 7 waves in the syllabus |
Included | Included |
02OperationsRetention, compaction and tiered storage, and why erasing a user takes more than a delete. Rebalances, poison records, a lost zone, rolling restarts, a KRaft quorum without its majority, and a broker that is slow but alive. The 8 waves in the syllabus |
Not included | Included |
03Stream ProcessingKafka Streams with transactions and exactly-once, state stores and standby replicas, the poll loop and the KIP-848 protocol, schema compatibility, and share groups for work that outgrows its partitions. The 5 waves in the syllabus |
Not included | Included |
04The PlatformQuotas for a noisy tenant, replaying history without starving live readers, the cross-zone bill, TLS and ACLs, large messages and Kafka Connect, then an exam that brings them together. The 7 waves in the syllabus |
Not included | Included |
05ResilienceFailing a region over with MirrorMaker 2 and its offsets, then three exams: an acquired cluster with bad defaults, a bigger Black Friday, and a night of overlapping failures. The 4 waves in the syllabus |
Not included | Included |
| Redis: Voxel Defense | ||
01First serviceKeys, TTLs and cache-aside. What invalidation has to do, and what a stampede does to the database behind the cache. The 6 lessons in the syllabus |
Included | Included |
02Data and memoryWhich structure fits which job (hashes, sets, lists, sorted sets) and what eviction throws away when memory runs out. The 6 lessons in the syllabus |
Not included | Included |
03Latency and atomicityWhere latency comes from: round trips, hot keys, unbounded commands. What MULTI/EXEC, WATCH and functions do and do not guarantee. The 6 lessons in the syllabus |
Not included | Included |
04Durability and availabilityWhat replication, RDB, AOF and WAIT each promise, and how Sentinel decides it is allowed to fail over. The 6 lessons in the syllabus |
Not included | Included |
05Redis ClusterHow 16,384 hash slots route keys, why multi-key commands need hash tags, and what MOVED and ASK are telling the client. The 6 lessons in the syllabus |
Not included | Included |
06Messaging and workPub/Sub against Streams, consumer groups and pending entries, and why reclaimed work needs idempotent handlers. The 6 lessons in the syllabus |
Not included | Included |
07Documents and retrievalJSON documents, search schemas, and the trade between recall and cost in vector search. The 6 lessons in the syllabus |
Not included | Included |
08Specialized structuresGEO, bitmaps, HyperLogLog, Bloom filters and time series: when an approximate answer is the right one. The 6 lessons in the syllabus |
Not included | Included |
09Production operationsACLs and TLS, connection pooling and uncertain retries, upgrades, and how much headroom a failure needs. The 6 lessons in the syllabus |
Not included | Included |
| Tutorials added later | ||
Every new systemOne payment covers the tutorials we have not made yet. Vote for the next one on the home page. Vote for the next system |
Chapter 1 | Included |
| Playing | ||
Runs in your browserNothing to install and no code to write. A laptop is best; a phone works. |
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A free accountEvery tutorial needs you to sign in, the free chapters too. There is no password: Google, or a link by email. The unlock belongs to the same account. Sign in |
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Progress on every deviceYour progress is saved to your account as you play, so you can stop anywhere and carry on in another browser. |
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SubscriptionThere is none. You pay once and keep access. |
None | None |
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Is it a subscription?
No. You pay once and keep access. Tutorials added later are included.
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Access starts the moment you pay, at your request, so the 14-day right of withdrawal ends then. Chapter 1 of every tutorial is free, so try before you buy. If something goes wrong with the payment, Link handles refunds.
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