BUILT TO BE OPENED
Tax software you can actually change.
Professional tools should offer more ways to solve a problem than submitting a request and waiting. Open source is the intended direction for PrepReturns.
On this page
Private today. A more open future in mind.
PrepReturns is being developed privately. There is no public engine repository, announced license, or source download on this site. The possibilities described here depend on a future release and its actual terms.
The direction is deliberate. We want practitioners and engineers to have more ways to understand, adapt, and improve professional tax software. A firm should be able to address a specific workflow need without always depending on one vendor’s priority queue.
That ambition affects how we think about architecture now: distinguish evidence from established facts, keep calculations explicit, preserve prepared history, and make output explainable. Clear boundaries make both inspection and future extension more useful.
Inspect what matters
Source availability could let qualified reviewers examine how a calculation is implemented, what its tests cover, and which assumptions define its scope. An engineer investigating a surprising result could distinguish a fact-projection issue from calculation, saved-state, or rendering behavior.
Most practitioners would not need to read the code themselves. They could benefit from independent specialists, contributors, or a firm-appointed reviewer being able to investigate it.
Open code does not prove that a result is correct or that someone has reviewed it. It creates an opportunity for scrutiny. The product must still explain its behavior through useful workpapers, diagnostics, and visible output.
Adapt the workflow and build the connection
A future open release could allow a firm to change a review sequence, add an internal handoff view, customize a workpaper, or build an export suited to its systems. The firm could do the work itself, hire someone, or collaborate with other users.
Integration is especially important. Tax information needs context as well as values: source, period, owner, review status, and the distinction between current working facts and a saved preparation. A useful interface preserves that meaning.
Documented APIs and broader external integrations remain part of PrepReturns’ direction. Open source could make it possible to add an endpoint or adapter where the main product has not yet addressed a need. It would complement stable interfaces, not eliminate the need to design them carefully.
Fix, contribute, or maintain a different path
If a user identifies a defect, a future contributor could propose a concrete repair with supporting evidence and tests. A useful improvement could benefit the shared project rather than remain a workaround inside one practice.
The main project would still need maintainers and an intended scope. Not every change would belong in the core. Some work could fit better in an extension; some could remain a firm-specific variation. A fork could provide continuity when a user’s needs and the main project’s direction diverge, subject to the published license.
Those options carry maintenance obligations. Tax changes, dependencies, forms, security, and compatibility continue to require attention. The goal is greater agency, with the costs and responsibilities visible.
Modifiable does not mean ungoverned
Changes to tax logic need strong research, independently derived expectations, regression coverage, output inspection, and professional review. Matching one example is not enough to establish a rule or its boundaries.
Version identity matters too. A saved preparation should remain connected to the facts and software behavior that produced it. A customized implementation should be distinguishable from a main-project release. A later correction should not erase the original evidence or silently rewrite a historical package.
PrepReturns’ development process already treats calculations, source workflows, state, browser behavior, and visible PDFs as separate layers of review. An open-source future should invite more people into that discipline.
Help shape the direction
No release date or license is being announced here. The current work is the S-Corp Engine, Alpha 14 human testing, and the next major direction of Form 1040.
We welcome conversations about contribution models, tax-rule review, interfaces, independent qualification, documentation, and sustainable maintenance. Tax-software companies, practitioners, engineers, and researchers can each bring a useful perspective.
The larger idea is simple: professional tax software should be something professionals can help shape. Let’s compare notes.
A conversation worth having.
Product, practice, architecture, or a different idea about what comes next.