FlagShark vs Uber Piranha

Same AST cleanup.
Different operating model.

Uber Piranha is genuinely excellent open-source software. If you have the engineering budget to operate a JVM CLI inside your CI, configure rule files, and own the integration, use Piranha and save the money. If you don't, we manage it for you.

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See the matrix →

▶ Uber Piranha

Open-source CLI from Uber. Apache 2.0. You run it.

Battle-tested at Uber-scale. 11 languages via Polyglot Piranha. Free as in beer and free as in speech. The trade-off: you operate the tool, write the rule files, run the CLI, ship the PRs yourself.

▶ FlagShark

Managed service with PR comments. We run it for you.

Same AST-based cleanup approach. Pre-tuned rules for every major flag SDK. Inline PR comments instead of CLI output. Runs on GitHub Actions infrastructure: no JVM, no rule file maintenance, no operational burden.

The honest math

Piranha is free. Operating it isn't.

The Apache 2.0 license costs nothing. The engineering time to make Piranha part of your daily workflow does. Real numbers from teams who have done both:

Initial integration & rule configuration8–16 hours
Monthly maintenance (rule updates, edge cases)4+ hours / month
Per-cleanup-cycle: identify flags, run CLI, review PRs2+ hours / week
Year 1 total engineer cost~$8,000–$12,000

FlagShark Team is $49/mo = $588/year. If your engineer time is worth more than $600/year, the math favors a managed service. If you genuinely enjoy operating dev infrastructure, Piranha is the better fit.

Side by side

Capabilities, compared honestly.

	OPEN SOURCE CLI Uber Piranha	★ MANAGED SERVICE FlagShark
License	Apache 2.0	SaaS · free Action MIT
Cost	$0 software · $8-12k/yr eng time	$0 (3 repos) · $49/mo (Team)
Languages	11	12
Setup time	8–16 hours (rules, CI integration)	30 seconds (8 lines of YAML)
JVM required	●	●
Runs automatically on every PR	●	●
PR comment inline with findings	●	●
Pre-tuned rules for major flag SDKs	●	●
Org-wide dashboard	●	●
Slack digest / weekly summary	●	●
Conservative on ambiguous removals	●	●
Deterministic output	●	●
Vendor-agnostic (multiple flag SDKs)	●	●

Honest take

When Piranha is the right call.

We'd rather you use Piranha than mis-sell you FlagShark. If your situation matches the below, save the $49/mo.

→You have a platform engineering team with capacity to operate CLI tools.
→You already run JVM-based infrastructure in your CI pipelines.
→Your organisation has a strong preference for self-hosted, vendor-agnostic OSS.
→You're cleanup-volume heavy enough that you want full control over rule files and edge-case handling.

Switch to FlagShark when: you don't have platform engineers to spare, you want PR-comment UX instead of CLI output, or you want a managed service that ships updates without you upgrading a JVM tool.

Common questions

Things OSS-aware teams ask.

Can I use both Piranha and FlagShark?

Yes. If you already have Piranha integrated, you can use FlagShark for detection, lifecycle tracking, and analytics while keeping Piranha for the actual removal. Most teams find FlagShark's integrated removal simpler.

Does FlagShark use Piranha under the hood?

No. FlagShark uses tree-sitter for flag detection plus custom AST transformation logic. We've invested heavily in post-processing to produce cleaner output than raw Piranha.

What if I already have Piranha integrated?

You can migrate gradually. Start using FlagShark on new repositories and benefit from the dashboard immediately. Over time, deprecate the Piranha setup as FlagShark handles more cleanup.

Is Piranha really free?

The software is free (Apache 2.0). But setup takes 8-16 hours, maintenance takes 4+ hours/month, and identifying flags to remove takes 2+ hours/week. At $150/hour engineer time, that's $8,000+ in year one.

Same cleanup. Less ops.

30s install. Free for 3 repos. No JVM, no rule files, no operational burden.

Start Free

View pricing

Piranha is free. Operating it isn't.

The Apache 2.0 license costs nothing. The engineering time to make Piranha part of your daily workflow does. Real numbers from teams who have done both:

Initial integration & rule configuration8–16 hours
Monthly maintenance (rule updates, edge cases)4+ hours / month
Per-cleanup-cycle: identify flags, run CLI, review PRs2+ hours / week
Year 1 total engineer cost~$8,000–$12,000

Capabilities, compared honestly.

	OPEN SOURCE CLI Uber Piranha	★ MANAGED SERVICE FlagShark
License	Apache 2.0	SaaS · free Action MIT
Cost	$0 software · $8-12k/yr eng time	$0 (3 repos) · $49/mo (Team)
Languages	11	12
Setup time	8–16 hours (rules, CI integration)	30 seconds (8 lines of YAML)
JVM required	●	●
Runs automatically on every PR	●	●
PR comment inline with findings	●	●
Pre-tuned rules for major flag SDKs	●	●
Org-wide dashboard	●	●
Slack digest / weekly summary	●	●
Conservative on ambiguous removals	●	●
Deterministic output	●	●
Vendor-agnostic (multiple flag SDKs)	●	●

When Piranha is the right call.

We'd rather you use Piranha than mis-sell you FlagShark. If your situation matches the below, save the $49/mo.

→You have a platform engineering team with capacity to operate CLI tools.

→You already run JVM-based infrastructure in your CI pipelines.

→Your organisation has a strong preference for self-hosted, vendor-agnostic OSS.

→You're cleanup-volume heavy enough that you want full control over rule files and edge-case handling.

Things OSS-aware teams ask.

Can I use both Piranha and FlagShark?

Does FlagShark use Piranha under the hood?

No. FlagShark uses tree-sitter for flag detection plus custom AST transformation logic. We've invested heavily in post-processing to produce cleaner output than raw Piranha.

What if I already have Piranha integrated?

You can migrate gradually. Start using FlagShark on new repositories and benefit from the dashboard immediately. Over time, deprecate the Piranha setup as FlagShark handles more cleanup.

Is Piranha really free?

Same AST cleanup.Different operating model.

Open-source CLI from Uber. Apache 2.0. You run it.

Managed service with PR comments. We run it for you.

Piranha is free. Operating it isn't.

Capabilities, compared honestly.

When Piranha is the right call.

Things OSS-aware teams ask.

Same cleanup. Less ops.

Same AST cleanup.Different operating model.

Open-source CLI from Uber. Apache 2.0. You run it.

Managed service with PR comments. We run it for you.

Piranha is free. Operating it isn't.

Capabilities, compared honestly.

When Piranha is the right call.

Things OSS-aware teams ask.

Same cleanup. Less ops.

Same AST cleanup.
Different operating model.

Same AST cleanup.
Different operating model.