Hook0

Hook0 is an open-source Webhooks-as-a-Service platform for delivering webhook events from an API call, with retries and security controls. Configurable two-phase retries handle delivery attempts, and a dead letter queue can hold events that use their retry budget. Payloads receive HMAC-SHA256 signatures and timestamps to help subscribers detect replay attacks. Delivery logs show requests, responses, status codes, and latency, and events can be replayed from the dashboard or API. A subscriber portal lets customers manage endpoint URLs, secrets, and event filters. Developers can use a REST API, Python and Node.js SDKs, and an MCP server for AI assistants. Hook0 says it connects with more than 3,000 apps through Zapier and also describes Integromat as an integration option. Its cloud service is hosted in France and keeps customer data in Europe; a self-hosted option is also listed. The free Developer plan allows 100 events per day and blocks excess events. Paid Cloud plans bill excess events instead. Startup costs €59/mo excl. VAT, and Pro costs €190/mo excl. VAT.

Hook0 combines delivery controls, inspection, and replay with both hosted and self-hosted deployment options. Check the free plan’s daily event cap and the paid plans’ stated prices and excess-event billing.

Hook0 may suit developers and teams that need webhook delivery, retry handling, event inspection, and replay. It offers both a hosted cloud service and a self-hosted option.

Hook0 is an open-source webhooks-as-a-service platform for teams that need to deliver, inspect, and replay events. It is best suited to SaaS and engineering teams that want delivery controls alongside a choice of hosted or self-hosted deployment. Its strongest case is the combination of retries, security, and operational visibility; check the free plan’s tight daily cap and paid plans’ event overage charges before committing.

Overview

Hook0 handles webhook delivery from an API call, with configurable two-phase retries and a dead letter queue for events that exhaust their retry budget. That gives teams a defined path for failed deliveries rather than leaving them to disappear after repeated attempts. Delivery logs show requests, responses, status codes, and latency, and events can be replayed from the dashboard or API—useful when diagnosing failures or recovering from a subscriber-side issue.

Payloads are signed with HMAC-SHA256 and timestamps, helping subscribers verify authenticity and detect replay attacks. Customers can manage endpoint URLs, secrets, and event filters through the subscriber portal. Hook0 also provides a REST API, Python and Node.js SDKs, and an MCP server for AI assistants.

Key features

• Delivery recovery: Configurable two-phase retries and a dead letter queue provide a practical way to handle exhausted delivery attempts.
• Inspection and replay: Request and response details, status codes, and latency help pinpoint delivery problems; replay is available through both dashboard and API.
• Subscriber controls: Customers can manage their own endpoint URLs, secrets, and event filters, reducing the need to handle every change centrally.
• Integrations: Hook0 says it connects to more than 3,000 apps through Zapier and also describes Integromat as an integration option.
• Security posture: Hook0 says it signs a DPA, discloses subprocessors, encrypts hourly backups, and restricts production access behind a two-factor VPN. Its cloud infrastructure is hosted by Clever Cloud in France, whose SOC 2 and ISO 27001 audits Hook0 cites.

Pricing

The free Developer plan is a narrow starting point for one developer and one application: it allows 10 event types, 10 subscriptions, and 100 events per day, with seven days of data retention and community support. Events above the daily cap are blocked, so it is a poor fit for production traffic that must not be dropped.

The free Self-hosted plan lets teams run their own instance under SSPL-1.0. It includes community support, but infrastructure scaling, 99.9% uptime, and managed updates are not included; the zero-price entry therefore shifts meaningful operating work to the customer.

Startup costs €59 /mo excl. VAT. It includes 25 developers, one application, 50 event types, 300 subscriptions, and 30,000 events per day, then charges €0.003/event. Fourteen days of data retention and email support with a three-day response make this the more bounded paid option for a team that can work within one application and its quota.

Pro costs €190 /mo excl. VAT, or €1,824/yr excl. VAT (20% off). It removes limits on developers, applications, event types, and subscriptions, raises the daily allowance to 100,000 events, and charges €0.0001/event above it. Thirty days of retention, priority email support with a three-day response, and static source IPs on demand make it the stronger fit for larger or more demanding integrations. Enterprise has custom pricing per year, with custom daily event volume and retention, a custom SLA and dedicated support, enterprise security and compliance, and static source IPs on demand.

Platforms

Hook0 is available on the web, with both hosted cloud and self-hosted deployment options. Its cloud service is hosted in France, and Hook0 says customer data stays in Europe. Teams choosing self-hosting should account for the infrastructure and operational responsibilities that the free plan leaves to them.

Who it's for

Hook0 suits teams building SaaS customer notifications, e-commerce workflows, IoT services, data synchronization, or communication between internal services. It is particularly compelling when delivery recovery, inspectable logs, replay, and subscriber-managed settings matter. A small project can start free, but the daily cap and blocked over-limit events call for caution; teams that need dependable production volume should assess the paid quotas and per-event charges.

Pros and cons

• Pro: Retries, a dead letter queue, detailed delivery logs, and replay address several stages of diagnosing and recovering from failed webhooks.
• Pro: HMAC-SHA256 signatures with timestamps and a subscriber portal give teams security and endpoint-management controls in the same service.
• Pro: Hosted and self-hosted options let teams choose between a managed service and running their own instance.
• Con: The free Developer plan blocks events beyond 100 per day, making it unsuitable for traffic that cannot tolerate drops.
• Con: Paid plans charge per event beyond their daily quotas, so usage above the included volume adds variable cost.
• Con: The free self-hosted option excludes scaling, 99.9% uptime, and managed updates, leaving those operational concerns to the team.

Alternatives

For a broader comparison, see Webhook Management Software. Consider Dispatch if its free plan’s 10,000 events per month and three-day history fit better than Hook0’s 100-event daily free cap; Dispatch drops over-limit events at ingress and limits the free tier to two members and public projects.

Hookdeck is another freemium webhook option. Hookdeck Outpost is worth comparing if an Apache-2.0 self-hosted option distributed as a Go binary and Docker container is a priority. Repost offers a free plan with a 50K events/month hard cap, one seat, three buckets, and 30-day history. Svix is an alternative with a listed Basic plan at $20 a month, including a 99.9% uptime SLA and 30-day payload retention. Webhook Management is another freemium option. RelayHQ is also worth comparing. Kiosk is a free, open-source PDF reader rather than a webhook-management service.

Verdict

Choose Hook0 if your team needs webhook delivery controls, replayable event records, and the flexibility to use hosted or self-hosted deployment. The recovery and inspection toolkit is its clearest advantage; look elsewhere if the free daily limit is too restrictive, or if you need to avoid overage billing and self-hosting responsibilities.