# pathway | Pathway | Knowledge Base | Instagit

Python ETL framework for stream processing, real-time analytics, LLM pipelines, and RAG.

GitHub Stars: 59.5k

Repository: https://github.com/pathwaycom/pathway

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## Articles

### [How Pathway Achieves Exactly-Once Processing Using Transaction-Based Semantics](/pathwaycom/pathway/pathway-exactly-once-processing-semantics)

Learn how Pathway implements exactly-once processing semantics with transaction-based commits and snapshot persistence for atomic data handling and reliable recovery. Discover the technical details.

- Tags: internals
- Published: 2026-03-06

### [Pathway Built-in Reduce Operators vs Custom UDFs: Architecture and Performance Differences](/pathwaycom/pathway/pathway-built-in-reducers-vs-custom-udfs)

Explore Pathway's built-in reduce operators versus custom UDFs. Understand the architecture and performance differences to choose the best option for your data processing needs.

- Tags: architecture
- Published: 2026-03-06

### [Schema Evolution in Pathway Data Pipelines: Versioned Metadata and the InnerSchemaField Abstraction](/pathwaycom/pathway/pathway-handle-schema-evolution)

Pathway tackles schema evolution with versioned metadata and the InnerSchemaField abstraction. Achieve backward-compatible changes in data pipelines without manual migrations.

- Tags: internals
- Published: 2026-03-06

### [Pathway Persistence Modes: RealtimeReplay, Batch, and SpeedrunReplay Use Cases](/pathwaycom/pathway/pathway-persistence-modes-use-cases)

Explore Pathway's persistence modes: RealtimeReplay for event-time testing, Batch for instant analytics, and SpeedrunReplay for fast CI validation. Understand unique use cases and characteristics.

- Tags: use-cases
- Published: 2026-03-06

### [How to Migrate Existing Batch ETL Processes to a Streaming Architecture Using Pathway](/pathwaycom/pathway/pathway-migrate-batch-etl-to-streaming)

Migrate batch ETL to streaming architecture with Pathway. Effortlessly switch connector mode retain transformation logic for real-time data processing.

- Tags: migration-guide
- Published: 2026-03-06

### [Pathway Monitoring and Observability Tools: OpenTelemetry, Prometheus, and Grafana Integration](/pathwaycom/pathway/pathway-monitoring-observability-tools)

Explore Pathway's seamless integration with OpenTelemetry Prometheus and Grafana for powerful pipeline observability with zero extra instrumentation. Gain deep insights now.

- Tags: how-to-guide
- Published: 2026-03-06

### [How to Implement Robust Error Handling and Retry Mechanisms in Pathway Pipelines](/pathwaycom/pathway/pathway-error-handling-retry-logic)

Implement robust error handling and retry mechanisms in Pathway pipelines. Learn how to use AsyncRetryStrategy and async_executor with back-off policies for automatic transient failure management.

- Tags: how-to-guide
- Published: 2026-03-06

### [Authentication and Authorization Methods for Pathway Connectors (S3, Azure): A Complete Guide](/pathwaycom/pathway/pathway-connector-authentication-authorization)

Explore Pathway's authentication and authorization methods for S3 and Azure connectors. Learn about credential-based access for S3 and account key authentication for Azure Blob Storage.

- Tags: how-to-guide
- Published: 2026-03-06

### [How Pathway Manages Backpressure and Optimizes Memory Usage in Streaming Dataflows](/pathwaycom/pathway/pathway-backpressure-memory-management)

Pathway optimizes streaming dataflows by managing backpressure and memory usage with a configurable max_backlog_size, preventing exhaustion and bounding RAM to specified capacity.

- Tags: internals
- Published: 2026-03-06

### [How to Implement Stateful Transformations Using Pathway Operators: Joins and Aggregations](/pathwaycom/pathway/pathway-stateful-transformations-joins-aggregations)

Learn to implement stateful transformations like joins and aggregations in Pathway. Explore how join contexts and grouped bucket reducers efficiently process streaming data with join, groupby, and reduce operators.

- Tags: how-to-guide
- Published: 2026-03-06

### [Pathway Rust Engine Underlying Architecture: How Differential Dataflow Powers Incremental Computation](/pathwaycom/pathway/pathway-rust-engine-differential-dataflow-architecture)

Explore Pathway's Rust engine architecture. Learn how Differential Dataflow powers incremental computation for low-latency stream processing. Discover the underlying DD collections.

- Tags: architecture
- Published: 2026-03-06

### [How Pathway Implements Windowing Operations: Tumbling, Sliding, and Session Windows](/pathwaycom/pathway/pathway-windowing-operations)

Learn how Pathway implements tumbling, sliding, and session windows using the unified Table.windowby() API. Understand temporal bucketing and aggregation for efficient data processing.

- Tags: internals
- Published: 2026-03-06

### [How to Optimize Pathway Performance for High-Throughput Real-Time Streaming Data](/pathwaycom/pathway/pathway-optimize-high-throughput-streaming)

Optimize Pathway performance for high-throughput real-time streaming data. Learn to tune connectors, scale horizontally, use Rust UDFs, and manage memory for peak efficiency.

- Tags: performance
- Published: 2026-03-06

### [Debugging and Troubleshooting Pathway Pipelines: Best Practices and Tools](/pathwaycom/pathway/pathway-debugging-best-practices)

Master Pathway pipeline debugging with best practices like tagged probes and schema verification. Troubleshoot efficiently and ensure reliable dataflow with expert tips and tools.

- Tags: best-practices
- Published: 2026-03-06

### [How Pathway External Vector Index Integrations Work: USearch and Qdrant Explained](/pathwaycom/pathway/pathway-external-vector-index-integration)

Discover how Pathway integrates USearch and Qdrant for unified vector search. Learn about the Rust trait abstraction powering seamless backend operations via the Python API.

- Tags: internals
- Published: 2026-03-06

### [How to Deploy and Manage Pathway Pipelines Using Kubernetes: Complete Guide](/pathwaycom/pathway/pathway-kubernetes-deployment)

Deploy and manage Pathway pipelines on Kubernetes. Containerize Python code, configure args via PATHWAY_SPAWN_ARGS, and orchestrate with StatefulSets for distributed execution and persistent state.

- Tags: how-to-guide
- Published: 2026-03-06

### [Key Differences Between Batch and Streaming Processing Modes in Pathway: A Complete Guide](/pathwaycom/pathway/pathway-batch-vs-streaming-modes)

Explore the key differences between batch and streaming processing in Pathway. Understand how static and streaming modes impact data ingestion, processing, and output for your applications.

- Tags: deep-dive
- Published: 2026-03-06

### [How to Configure Snapshot Intervals and State Checkpointing in Pathway for Durability](/pathwaycom/pathway/pathway-configure-snapshot-intervals-checkpointing)

Configure Pathway snapshot intervals and state checkpointing to ensure durability. Learn how to set snapshot intervals and access modes for reliable data persistence.

- Tags: how-to-guide
- Published: 2026-03-06

### [How Pathway's Incremental Computation Model Enables Real-Time Data Processing](/pathwaycom/pathway/pathway-incremental-computation-model)

Discover how Pathway's incremental computation model achieves real-time data processing by updating only changed data with its efficient Rust-based Differential Dataflow engine.

- Tags: internals
- Published: 2026-03-06

### [What Persistence Backends Does Pathway Support for State Recovery and Fault Tolerance?](/pathwaycom/pathway/pathway-supported-persistence-backends)

Discover Pathway's state recovery and fault tolerance options. Explore support for Filesystem, Amazon S3, Azure Blob Storage, and a Mock backend for robust applications.

- Tags: api-reference
- Published: 2026-03-06

### [How to Implement Custom Connectors in Pathway for Unsupported Data Sources](/pathwaycom/pathway/pathway-implement-custom-connectors)

Learn to implement custom connectors in Pathway for unsupported data sources. Subclass ConnectorSubject, use self.next(), and wrap with read() for streaming data.

- Tags: how-to-guide
- Published: 2026-03-06

### [At-Least-Once vs Exactly-Once Consistency Guarantees in Pathway: A Complete Guide](/pathwaycom/pathway/pathway-at-least-once-vs-exactly-once-consistency)

Understand at-least-once vs exactly-once consistency guarantees in Pathway. Prevent data loss or ensure no duplicates even after crashes. Learn about Pathway's delivery options.

- Tags: deep-dive
- Published: 2026-03-06

### [How Pathway Handles Late-Arriving Data and Out-of-Order Events in Streaming Pipelines](/pathwaycom/pathway/pathway-handle-late-data-out-of-order-events)

Pathway tackles late-arriving data and out-of-order events in streaming pipelines with ignore_late and postpone operators

- Tags: how-to-guide
- Published: 2026-03-06