Kafka

⚡ 142,830 events/secoffset: 9,847,231partitions: 12⚠ consumer lag: HIGHthroughput 98.4%

Master the Stream. Certify the Skill.

Hands-on Kafka and Flink labs for engineers who need to debug consumer lag, build real-time pipelines, and pass certification — before the migration deadline.

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No credit card · First lab always free · 94% certification pass rate

ConsumerLagFix.java — Lab 3

✓ Tests passing

// Lab 3: Fix Consumer Group Lag
const consumer = new KafkaConsumer<String, Event>(props);
 
// ⚠ consumer lag: 8,420 messages behind
consumer.subscribe(List.of("events"));
 
// ✓ Fix: tune poll records + commit interval
props.put("max.poll.records", 500);
props.put("auto.commit.interval.ms", 1000);
// lag resolved in 4.2s ✓

● Live cluster connectedkafka:9092 | flink:8081

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94%

first-attempt pass rate

CCDAK Certification

Confluent Certified Developer for Apache Kafka — recognized by 80% of Fortune 500 companies.

CCDAKCCAAKFlink Ops

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Live completions

Riya P.earnedFlink Certification12 min ago

Marcus T.earnedCCDAK28 min ago

Sofia L.earnedCCAAK41 min ago

David K.earnedFlink Certification1 hr ago

Priya S.earnedCCDAK1 hr ago

James W.earnedCCAAK2 hrs ago

Elena R.earnedFlink Certification2 hrs ago

Amir H.earnedCCDAK3 hrs ago

Yuki T.earnedCCAAK3 hrs ago

Chen W.earnedFlink Certification4 hrs ago

Nadia M.earnedCCDAK4 hrs ago

Tyler B.earnedCCAAK5 hrs ago

Riya P.earnedFlink Certification12 min ago

Marcus T.earnedCCDAK28 min ago

Sofia L.earnedCCAAK41 min ago

David K.earnedFlink Certification1 hr ago

Priya S.earnedCCDAK1 hr ago

James W.earnedCCAAK2 hrs ago

Elena R.earnedFlink Certification2 hrs ago

Amir H.earnedCCDAK3 hrs ago

Yuki T.earnedCCAAK3 hrs ago

Chen W.earnedFlink Certification4 hrs ago

Nadia M.earnedCCDAK4 hrs ago

Tyler B.earnedCCAAK5 hrs ago

Certified engineers now working at

Stripe

Uber

Airbnb

Confluent

Netflix

Shopify

Datadog

live lab environment

Real clusters. Real problems.
Not toy examples.

L01BeginnerFREE

Build Your First Producer

Configure a KafkaProducer, publish events to a partitioned topic, and observe offset commits in real time.

JavaKafka APITopics⏱ 25 min

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L03Intermediate

Debug Consumer Group Lag

Diagnose a consumer group 8,420 messages behind. Tune max.poll.records and commit intervals. Watch the lag gauge drop to zero.

Consumer GroupsLagTuning⏱ 40 min

Unlock with Pro

L07Advanced

Deploy Flink on Live Streams

Write a stateful Flink job consuming from Kafka, apply a sliding window aggregate, and checkpoint to S3.

FlinkWindowingCheckpoints⏱ 55 min

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certification tracks

Pick your track.
Ship before the deadline.

Compare Certification Tracks →

CCDAK

Kafka Developer

Confluent Certified Developer for Apache Kafka

Duration

4 weeks

Labs

18 hands-on

Level

Mid-level

01Kafka Architecture

02Producers & Consumers

03Kafka Streams API

04Schema Registry

05Consumer Group Tuning

06Exam Prepexam

completion rate94%

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CCAAK

Kafka Administrator

Confluent Certified Administrator for Apache Kafka

Duration

3 weeks

Labs

14 hands-on

Level

DevOps / SRE

01Cluster Setup

02Monitoring & Alerting

03Security & ACLs

04Performance Tuning

05Disaster Recovery

06Exam Prepexam

completion rate94%

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FLINK

Flink Stream Processing

Real-time stateful stream processing at scale

Duration

5 weeks

Labs

22 hands-on

Level

Advanced

01Flink Architecture

02DataStream API

03Windowing & Watermarks

04State & Checkpointing

05Kafka + Flink Pipelines

06Production Deploymentsexam

completion rate94%

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1M+

Engineers trained

across 140 countries

94%

First-attempt pass rate

CCDAK & CCAAK combined

$95K

Median salary post-cert

US Kafka professionals

20min

To first pipeline

lab environment spins up instantly

I was handed a Confluent cluster with zero documentation. After the CCAAK track, I tuned it for 3x throughput in a week. The labs are the real thing — not toy examples.

Marcus T.

Senior DevOps Engineer, Stripe

✓ CCAAK

Our team needed CCDAK certification before a platform migration deadline. Six engineers passed on first attempt. The consumer lag lab alone was worth the subscription.

Priya S.

Platform Engineering Lead, Airbnb

✓ CCDAK

I spent two years in batch thinking. The Flink windowing lab clicked something — I rebuilt our entire analytics pipeline in a weekend. Backpressure gauge finally hit zero.

David K.

Senior Backend Engineer, Datadog

✓ Flink

your topology. online. certified.

Every node lighting up green.
Start with Lab One. Free.

No form. No credit card. Click once, land in a live Kafka lab environment. Your first pipeline in under 20 minutes.

Start Lab One Free View all 54 labs

✓94% pass rate✓18 Kafka labs✓22 Flink labs✓Live clusters included

Master the Stream. Certify the Skill.

Real clusters. Real problems.Not toy examples.

Build Your First Producer

Debug Consumer Group Lag

Deploy Flink on Live Streams

Pick your track.Ship before the deadline.

Kafka Developer

Kafka Administrator

Flink Stream Processing

Every node lighting up green.Start with Lab One. Free.

Real clusters. Real problems.
Not toy examples.

Pick your track.
Ship before the deadline.

Every node lighting up green.
Start with Lab One. Free.