This document is a community-maintained roadmap of the upcoming releases and features (at a high-level).
The document contains only estimations, no guaranteed feature / release dates. 

See also the time-based release model.

Last update: Apr 2, 2024

Next scheduled major/minor release: 1.20.0
Feature freeze (branch forking):  tbd
Code freeze (first voting RC):  tbd
Release date: TBD

¹ These releases were considered emergency releases connected to the Log4j Zero Day vulnerability (CVE-2021-44228; see related Flink Blog Post)

ARCHIVE

Past releases

Flink 1.1 (August 2016)

• Session Windows and Allowed lateness
• Table API and SQL on Calcite
• Metrics system
• Scala API for CEP
• Graph generators and new Gelly library algorithms
• Continuous File Sources
• Kinesis Connector
• Cassandra Connector

Flink 1.2

• Dynamic Scaling / Key Groups (FLINK-3755) (Design Doc)
• Rescalable Non-Partitioned State (FLIP-8)
• Backwards compatible savepoints (FLINK-4797)

• Integrate Flink with Apache Mesos (FLINK-1984) (Design Doc)

• Secure Data Access (FLINK-3930) (Design Doc)
• Queryable State (FLINK-3779)
• Async I/O (FLIP-12)
• Metrics in Webinterface (FLIP-7)
• Kafka 0.10 support (FLINK-4035)
• Table API: Group Window Aggregates (FLINK-4691, FLIP-11)
• Table API: Scalar Functions (FLINK-3097)

Flink 1.3

• (Large) State Handling / Recovery:

  • Incremental / lightweight snapshots for checkpoints (FLINK-5053)

  • Asynchronous snapshots for heap-based state backends (FLINK-6048, FLINK-5715)

  • Allow upgrades to state serializers (FLINK-6178)

  • Recover job state at the granularity of operator (FLINK-5892)

  • Fine-grained recovery (beta) (FLINK-4256)

• Streaming APIs:

  • Expose Broadcast Operator State through public APIs (FLINK-5991)

  • Side Outputs (FLINK-4460)

  • Extending AllWindow Function Metadata (FLINK-5157, FLINK-4997)

  • Access to Per-Window state in ProcessWindowFunction (FLINK-5929)

  • Add support for "Distributed Cache" in streaming applications (FLINK-6177)

• Deployment & Tooling:

  • Flink History Server (FLINK-1579)

  • Flink automatically manages TM network buffer (FLINK-4545)

  • Add Datadog HTTP metrics reporter (FLINK-6013)

  • Add watermark monitoring to JobManager web frontend (FLINK-3427)

• Table API / SQL:

  • Support for Retraction in Table API / SQL (FLINK-6047)

  • Support for non-windowed aggregations in streaming Table API / SQL (FLINK-6216)
  • Support for append, upsert and retraction StreamTableSinks (FLINK-6093)

  • Integrate time indicators for Table API & SQL (FLINK-5884)

  • Support for group windows in (batch + streaming) SQL (TUMBLE, HOP, SESSION) (FLINK-6261,FLINK-6011)
  • Support for OVER windows in streaming Table API and SQL (FLINK-4557)
  • Support for QueryConfig for streaming queries to specify state retention interval (FLINK-6491)
  • Support for user-defined aggregation functions (FLINK-5564)
  • Support for standard deviation and variance aggregation functions (FLINK-4604)

  • Support for TableSources with filter push down (FLINK-3849,

  • Support for external catalogs (FLINK-5570)

  • Add KafkaAvroTableSource (FLINK-3871)

  • Add HBaseTableSource (FLINK-2168)

  • Add CUBE/ROLLUP/GROUPING SETS operator in batch SQL (FLINK-5303)

  • Support for DISTINCT GROUP BY aggregates for batch SQL (FLINK-3849)
  • Add flink-table.jar to ./opt folder (FLINK-6247)
  • Support for more scalar functions (SIN, COS, TAN, DEGREES, PI etc.) (FLINK-6112)
• Connectors:

  • Elasticsearch 5.x support (FLINK-4988)

  • Implement rescalable non-partitioned state for Kinesis Connector (FLINK-4821)

  • Transparent shard discovery for Kinesis Consumer (FLINK-4577)

  • Allow Kinesis Consumer to start from specific timestamp / Date (FLINK-4523)

  • Allow setting custom start-offsets for the Kafka consumer (FLINK-3123)

  • Allow out-opt from offset committing for the Kafka consumer (FLINK-3398)

• CEP library improvements:

  • Make CEP operators rescalable (FLINK-5420)

  • Late element handling (FLINK-6205)

  • Support for quantifiers (*,+,?) to CEP's pattern API (FLINK-3318)

  • Support for different continuity requirements (FLINK-6208)

  • Add support for iterative conditions (FLINK-6197)

  • Clean up state whenever possible (FLINK-5174)
• Gelly Library:
  • Unified driver for running Gelly examples (FLINK-4949)

  • PageRank algorithm for directed graphs (FLINK-4896)

  • Add Circulant and Echo graph generators (FLINK-6393)

Flink 1.13

You can find a list of planned features for the 1.13 release in this Wiki page.