Staxly

Inngest vs LangSmith

Durable functions + event-driven workflows for modern apps
vs. LLM observability, testing & evaluation — by LangChain

Inngest websiteLangSmith website

Pricing tiers

Inngest

Free
$0. 50K steps/mo + 1K concurrent executions. 7-day log retention. 1 environment.
Free
OSS (self-host)
Free forever. Inngest Dev Server + self-hosted Inngest runtime. Apache 2.0.
$0 base (usage-based)
Starter
$20/mo. 250K steps/mo. 5K concurrency. 14-day retention. 3 envs.
$20/mo
Pro
$75/mo. 1M steps/mo. 10K concurrency. 30-day retention. Priority support.
$75/mo
Enterprise
Custom. SSO, HIPAA, dedicated clusters, self-host with Inngest Enterprise.
Custom
Inngest website

LangSmith

Developer (Free)
Free forever. 5,000 traces/month. 14-day retention. 1 seat. Basic evaluations.
Free
Plus
$39/seat/month. 10k base traces included ($2.50 per 1k overage). Full evaluations, custom dashboards, email support.
$39/mo
Enterprise
Custom. Self-host option, SSO, custom retention, dedicated support.
Custom
LangSmith website

Free-tier quotas head-to-head

Comparing free on Inngest vs developer on LangSmith.

MetricInngestLangSmith
No overlapping quota metrics for these tiers.

Features

Inngest · 14 features

  • AgentKitBuild AI agents as durable Inngest functions.
  • Auto RetriesConfigurable retries with exponential backoff.
  • Concurrency ControlsPer-function and per-user concurrency limits.
  • Cron TriggersScheduled functions via cron syntax.
  • DebounceCoalesce rapid-fire events into one execution.
  • Dev ServerLocal Inngest runtime for dev.
  • Durable Stepsstep.run, step.sleep, step.waitForEvent.
  • Event SystemTyped events with schemas.
  • Fan Out / BatchingProcess many events in parallel with batch control.
  • Priority LanesRoute premium customers to faster execution.
  • Rate LimitingThrottle events per key.
  • RealtimeStream function output to clients.
  • ReplayRe-run past functions with new code.
  • Self-HostOSS runtime — run your own Inngest.

LangSmith · 14 features

  • AlertsThreshold alerts on latency, cost, eval metrics.
  • Annotation QueuesHuman-review workflows for trace quality rating.
  • Custom DashboardsAggregate metrics dashboards per project/tag.
  • DatasetsCollect examples → use as eval sets or training data.
  • EvaluationsLLM-as-judge, embedding similarity, custom Python evaluators, offline batch eval
  • LangChain IntegrationAuto-trace any LangChain/LangGraph run with env var.
  • LangGraph IntegrationFirst-class trace + eval for LangGraph agents.
  • LLM TracingAutomatic trace every LLM call + tool call + chain step.
  • OpenTelemetry ExportExport traces as OTLP to Datadog/Honeycomb/etc.
  • PlaygroundTest prompts + models inline before deploying.
  • Prompt CanvasVisual prompt editor with live test + eval.
  • Prompt HubPublic + private prompt library with versioning.
  • Self-Hosted (Enterprise)Docker + k8s deployment in your infra.
  • Threads + SessionsGroup traces into conversational sessions.

Developer interfaces

KindInngestLangSmith
CLIinngest-cli (dev server)LangSmith CLI
SDKinngestgo, inngest (Python), inngest (TS/Node)langsmith-js, langsmith-python
RESTInngest REST APILangSmith REST API
MCPInngest MCPLangSmith MCP
OTHERInngest Cloud DashboardLangSmith Dashboard
Staxly is an independent catalog of developer platforms. Outbound links to Inngest and LangSmith are plain references to their official websites. Pricing is verified against vendor pages at publication time — reconfirm before buying.

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