What is the cheapest way to get error tracking as a solo founder?

Every tool on this page has a $0 plan: Sentry Developer, Bugsnag Free, Rollbar Free, LaunchDarkly Developer (where hosted highlight.io went), PostHog and Mushi Free Cloud. Sentry, PostHog and Mushi can also be self-hosted for free, and highlight.io's open-source repo documents a free hobby install. Bugsnag's on-premise edition is Enterprise-only, and Rollbar is cloud-only. The real cost is the afternoon you spend reading what they collected.

Which of these explain the bug instead of showing a stack trace?

Most now have something. Sentry's Seer is an add-on to Team, Business or Enterprise at $40 per active contributor per month. Rollbar Resolve (public beta) finds the root cause, writes a code change, runs your tests in a sandbox and opens a pull request, using AI credits the Free plan does not include. PostHog has a "Fix with AI" prompt on every error issue and, in open beta, draft pull requests for recurring errors: 3 a month free, then $15 each. Bugsnag's pricing page lists no AI feature; SmartBear's MCP server, in beta, offers AI fix suggestions in the IDE. Mushi writes a plain-English diagnosis on every plan: up to 50 a month on Free Cloud (a hard stop; later reports are kept but not diagnosed until next month), 500 included on Indie, and unlimited self-hosted with your own LLM key. Like the others, it is an AI reading and can be wrong. The report it starts from is what a user said and saw, not only what threw.

Do I have to rip out Sentry to try Mushi?

No. Mushi runs standalone or alongside Sentry: a Sentry issue-alert webhook sends errors into Mushi's queue on every plan, and with the outbound Sentry plugin (Indie and above, or self-hosted) merging the fix resolves the Sentry issue.

How current is this page?

Every number was read on 2026-09-21 from the vendor's own pages, linked under each tool's name. A value that cannot be confirmed on a review date is marked unverified instead of guessed. The next scheduled review is 2026-12-21.

Sentry alternatives for solo founders

If you are one person shipping an app to real users, the question is not “which error tracker is best”. It is “which one will I still be reading in month three”. This page compares six tools on the four things that decide that for a solo builder: what the free tier caps, whether you can run it yourself, whether it explains the bug or only reports it, and who each one is really for.

Mushi is on the list. We tried to describe the others in their own terms, and every number links to the page it came from.

Facts checked 2026-09-21 against the linked sources. Next review due 2026-12-21. Rows marked “unverified — check before publishing” could not be confirmed on that date.

The table

Tool	Free tier	Self-host	AI diagnosis / fix	Pick this if
Sentry source · Seer billing · self-host	Developer: 5k errors/mo, one user	Yes, getsentry/self-hosted (Docker; 4 cores / 16 GB RAM); no Seer	Seer: $40 per active contributor/mo, an add-on to Team ($26/mo), Business or Enterprise	You want the deepest error, tracing and release tooling and expect to grow into a team plan.
Bugsnag source · on-premise · MCP	Free: $0, 1 user, 7.5K events + 1M spans/mo, 7-day retention	Yes, an "On-premise" edition on the Enterprise plan only; price on request	None on the pricing page; SmartBear's MCP server (beta) offers AI fix suggestions in your IDE	You want error and performance monitoring free for one person, with a paid step from $20/mo (Select) and an on-premise option if you ever need one.
Rollbar source · Resolve · cloud-only	Free: 5,000 occurrences + 1,000 session replays/mo; Essentials from $9/mo for 10,000 occurrences	No, cloud-only	Rollbar Resolve (public beta): root cause, a code change tested in a sandbox, and a PR. Needs AI credits and the Rollbar GitHub App; the Free plan includes none	Your volume is low, you want a small replay allowance for free, cloud-only is fine, and you would pay for AI credits to get fix PRs.
highlight.io (now LaunchDarkly) source · LaunchDarkly pricing · self-host	Hosted highlight.io shut down on 2026-02-28. The hosted free path is LaunchDarkly Developer: $0, 5K session replays, 5K errors, 10M logs, 10M traces/mo	Yes, from the open-source repo: a one-line Docker hobby install for under 10k sessions and 50k errors/mo	None listed in the open-source README	You want replay, errors, logs and traces in one open-source box you run yourself at hobby scale, or you are happy to move to LaunchDarkly for the hosted version.
PostHog source · Fix with AI · PR pricing	5K replays + 100K exceptions + 1M events/mo, 500 AI credits, no card, 1 project	MIT open-source product available	"Fix with AI" prompt on every error issue; Self-driving (open beta) opens draft PRs for recurring errors, 3 free/mo then $15 per PR	You already want product analytics and replay, and error tracking can ride along.
Mushi Mushi source	Free Cloud: 50 diagnoses/mo (hard stop), 1 seat, 7-day retention, no card	Yes, free, AGPLv3 server on your own Supabase project, one command; bring your own Anthropic key	Included within the plan's diagnosis quota (50/mo on Free Cloud): plain-English diagnosis + fix prompt, which can be wrong; MCP into Cursor / Claude Code; optional agent-drafted PR	You did not write most of the code, your users tell you about bugs, and you want the fix in your editor.

How to read it

Free tiers. All six have a $0 plan. For highlight.io that now means LaunchDarkly’s Developer plan: LaunchDarkly bought highlight.io in April 2025 and shut the hosted service down on 28 February 2026. The caps are measured in different units (errors, events, occurrences, spans, replays, diagnoses), so compare them against your own volume rather than each other. A side project with a few hundred users rarely reaches any of these limits.

Self-hosting. Sentry, PostHog and Mushi publish a free self-hosted path, and highlight.io’s open-source repo still documents a one-line Docker hobby install sized for small projects (the limits are in the table). Sentry’s needs a real machine (4 cores, 16 GB RAM per its docs) and leaves out Seer. Mushi’s deploys with one command onto your own Supabase project (the free tier works) and includes the diagnosis when you bring your own Anthropic key. Bugsnag sells an on-premise edition on its Enterprise plan, priced on request. Rollbar is cloud-only.

AI diagnosis and fixes. Most of these now have something; what differs is the price and where it starts. Sentry’s Seer is an add-on to Team, Business or Enterprise, priced per active contributor (Sentry’s pricing docs ). Rollbar Resolve , in public beta, finds the root cause, writes a code change, runs your tests in a sandbox and opens a pull request; it runs on AI credits, and the Free plan includes none. PostHog puts a “Fix with AI” prompt on every error issue, and its Self-driving beta opens draft pull requests for recurring errors, with a small free allowance each month and a price per PR after that . Bugsnag’s pricing page lists no AI feature; SmartBear’s MCP server, in beta, offers AI fix suggestions in the IDE. highlight.io’s README lists none. Mushi’s diagnosis and fix prompt run on every plan, including free and self-hosted with your own key, and they start from what a user reported and the screen they were on.

Who it is for. Sentry, Bugsnag and Rollbar were built around error monitoring, and each has a free plan a solo developer can use. PostHog was built around product analytics, with replay and error tracking alongside; highlight.io was built around replay. Mushi was built for a builder who did not write most of the code and hears about bugs from users; the output is the diagnosis and the fix, in the editor.

What this page does not claim

It does not claim Mushi is cheaper at scale, and it does not claim feature parity with Sentry on tracing, profiling or platform coverage. If you need those, Sentry is the right answer and Mushi runs alongside it: a Sentry issue-alert webhook sends errors into Mushi’s queue, and with the outbound Sentry plugin (Indie and above, or self-hosted) merging the fix resolves the Sentry issue. See Sentry vs Mushi.

Start free — 50 diagnoses/mo, no card

Frequently asked questions

What is the cheapest way to get error tracking as a solo founder?: Every tool on this page has a $0 plan: Sentry Developer, Bugsnag Free, Rollbar Free, LaunchDarkly Developer (where hosted highlight.io went), PostHog and Mushi Free Cloud. Sentry, PostHog and Mushi can also be self-hosted for free, and highlight.io's open-source repo documents a free hobby install. Bugsnag's on-premise edition is Enterprise-only, and Rollbar is cloud-only. The real cost is the afternoon you spend reading what they collected.
Which of these explain the bug instead of showing a stack trace?: Most now have something. Sentry's Seer is an add-on to Team, Business or Enterprise at $40 per active contributor per month. Rollbar Resolve (public beta) finds the root cause, writes a code change, runs your tests in a sandbox and opens a pull request, using AI credits the Free plan does not include. PostHog has a "Fix with AI" prompt on every error issue and, in open beta, draft pull requests for recurring errors: 3 a month free, then $15 each. Bugsnag's pricing page lists no AI feature; SmartBear's MCP server, in beta, offers AI fix suggestions in the IDE. Mushi writes a plain-English diagnosis on every plan: up to 50 a month on Free Cloud (a hard stop; later reports are kept but not diagnosed until next month), 500 included on Indie, and unlimited self-hosted with your own LLM key. Like the others, it is an AI reading and can be wrong. The report it starts from is what a user said and saw, not only what threw.
Do I have to rip out Sentry to try Mushi?: No. Mushi runs standalone or alongside Sentry: a Sentry issue-alert webhook sends errors into Mushi's queue on every plan, and with the outbound Sentry plugin (Indie and above, or self-hosted) merging the fix resolves the Sentry issue.
How current is this page?: Every number was read on 2026-09-21 from the vendor's own pages, linked under each tool's name. A value that cannot be confirmed on a review date is marked unverified instead of guessed. The next scheduled review is 2026-12-21.