Arize Phoenix OSS is MIT-licensed, free, unlimited. One Docker command to full observability. When you’re ready for production-grade monitoring, alerting, and enterprise controls, Arize AX picks up exactly where Phoenix leaves off. One company. One roadmap. Built for agents.
Arize vs. Langfuse
Same open-source DNA.
Same open-source DNA.
Different trajectory.
Trusted in production by
Open source that grows with you.
Langfuse
Open source, new ownership.
Langfuse built a strong open-source community and a solid tracing foundation. Then ClickHouse acquired them before they closed their Series A. The team is talented, the tooling is real, but the roadmap now belongs to a database company, and database companies optimize for what sells databases.
What AI builders are saying
from field interviews
We were hitting tooling gaps with Langfuse. Limited visibility into what was happening, too much manual debugging. We needed to see the full picture without stitching logs together ourselves.
Anonymous Engineer
Autonomous vehicle company
Langfuse worked fine early on, but we kept hearing from other teams that hit walls at scale. Arize’s database architecture is built for enterprise volume. That mattered when we started planning for production traffic.
Anonymous Engineer
Security platform
We have regulatory requirements and needed real SLAs. Langfuse’s support terms didn’t meet our bar. When you’re in a regulated industry, a 30-day SLA isn’t going to cut it.
Anonymous Engineer
Financial data platform
Where the architecture diverges
Open source is the starting line, not the finish
ROADMAP
Whose roadmap is it?
ClickHouse acquired Langfuse before the team closed their Series A. The stated rationale is infrastructure alignment – Langfuse v3 already runs on ClickHouse.
But infrastructure alignment means product priorities follow database strategy, not AI observability strategy. Arize is an independent AI company. Our roadmap is set by what AI engineering teams need, not what sells more database seats.
DATA INFRASTRUCTURE
General-purpose OLAP vs. purpose-built AI
ClickHouse is a strong analytics engine. It was designed for logs, metrics, and columnar queries at scale.
AI observability is a different problem – embeddings, agent decision trees, eval telemetry with high cardinality across sessions, spans, and tool calls. Arize built adb for exactly this workload. Purpose-built beats repurposed when your agents are in production.
THE UPGRADE PATH
From open source to enterprise - without switching vendors
Phoenix is MIT-licensed, free, unlimited. One Docker command. When you need production monitoring with automated alerting, SSO/RBAC, SOC 2 compliance, and Alyx – you upgrade to AX. Same platform, same data, same team.
Langfuse’s upgrade path now routes through ClickHouse’s enterprise sales motion. Different incentives, different priorities.
SELF-HOSTING
Open source shouldn't mean ops burden
Langfuse self-hosted requires Kubernetes, managed Postgres, Redis, S3, and a ClickHouse cluster. Teams report 40-80 hours of engineering setup and $3-4K/month in ongoing infrastructure costs. Docker Compose deployments lack HA and aren’t production-ready.
Phoenix runs with one Docker command. Arize AX handles the infrastructure so your team ships AI, not YAML.
When Langfuse is the right call
If you’re early-stage, self-hosting is a hard requirement, and you need basic tracing and prompt management to get started – Langfuse’s community and documentation are genuinely strong.
When your agents hit production and you need depth, scale, and a roadmap you can trust – we’ll be here.
Where the difference is most felt
Infrastructure at Scale
Trillions of data points. No tradeoffs.
Arize's purpose-built AI database (adb) handles trillions of data points with up to 100x cost advantage over traditional observability platforms. Open formats, no vendor lock-in. Iceberg and Parquet native.
Production Monitoring
First trace to full production visibility
Continuous real-time monitoring with automated alerting. Surface regressions before users notice. One system from first trace through enterprise scale.
Alyx
Find what you didn't know to look for
Alyx is a Cursor-like AI engineering agent that surfaces failure clusters, drift signals, and anomalous reasoning paths automatically. Closes the loop before you know it's open.
Enterprise VPC Deployment
One deployment. Total control.
One Kubernetes cluster. No outbound calls to third-party servers. Predictable K8s-native costs - no surprises. Your data, your infrastructure, your rules.
No ops burden
Arize AX is fully managed. No Postgres, Redis, S3, or ClickHouse clusters to wrangle. Your team ships AI, not infrastructure.
Predictable costs
K8s-native architecture means fixed, plannable infrastructure costs. No self-hosting sticker shock at scale.
Simpler operations
One Kubernetes cluster to manage. No split infrastructure, no multi-cloud coordination.
AI evolved from ML. So did we.
We’re Jason and Aparna.
We built the foundational ML infrastructure at Uber, Apple, and TubeMogul.
Before LLMs existed, we watched models break in production with nothing to fix them. So we started Arize to fix it.
Our mission since 2020: make AI work.
ML first. Then LLMs. We shipped the first open-source library for LLM evaluation: Phoenix.
Now agents.
That’s Arize AX — the Agent Experience.
