Ably vs Windmill
Side-by-side trajectory, velocity, and editorial themes.
Ably is spinning up an AI-agent transport layer at 0.x speed
Ably is iterating hard on a new AI Transport SDK — four releases (0.2 through 0.5) in about a month — aimed at making agent conversations durable, resumable, and branchable over its realtime channels. Alongside it, the core Pub/Sub and Chat SDKs keep getting steady, mostly incremental maintenance: React hook ergonomics, presence reliability fixes, and better LiveObjects visibility in the dashboard.
The AI Transport line is the story. Each release layers on capability that matters for production agents — declarative codecs, external data hydration, and now durable execution that survives process restarts inside frameworks like Temporal and Vercel's WDK. Ably is positioning its realtime infrastructure as the transport substrate for AI agents, not just chat and pub/sub, while keeping the mature core SDKs stable. The frequent breaking changes signal a product still finding its API shape.
Expect the AI Transport SDK to keep its fast breaking-change cadence toward a 1.0 with a stabilized session/run API, and likely SDKs beyond JS as the surface settles. The entries don't yet indicate a GA date.
Windmill is quietly turning its orchestrator into a DuckLake-native data platform.
Windmill remains a script-and-workflow orchestrator, but its recent output has narrowed almost entirely to the data layer: DuckLake materialization, partitioned assets, freshness, and now schema contracts. The changelog reads less like a general automation tool and more like a managed lakehouse being assembled on top of the existing job engine, with most of the heavier machinery gated to Enterprise Edition.
The direction is a governed, self-maintaining data platform: fork-scoped data environments for isolated iteration, freshness SLAs with an auto-healing watchdog, scheduled compaction and retention, range backfills, and save-time schema validation between producers and consumers. Each release hardens a different operational corner of the DuckLake stack rather than adding breadth, so Windmill is deepening into data-ops rather than widening its surface.
Schema contracts shipped as non-blocking warnings, so the next likely move is to tighten that loop — enforceable contracts or richer lineage on the DuckLake graph. Continued Enterprise gating of the data-ops features (maintenance, freshness watchdog, range backfill) also points to a productized data-platform tier.
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