OneSig Atlas

Tax readiness and deployment command center.

No tax transformation should run without one.

Audit-grade readiness, proven on your data.Audit-grade readiness, proven on your data.

Tax programs fail on data, requirements, and ownership.

Atlas finds what will break, assigns every fix, preserves every decision, and gives your ASP or SI a working implementation file.

E-invoicing today. Any data-driven tax mandate next.

Free · Limited sample · Brandable findings

Leading E-Invoicing Consultancy · July 2026

Built by ex

A rejected invoice is revenue you cannot collect.

The schema may pass. The platform may work.

But incorrect master data, missing rules, and unresolved decisions can still stop the invoice.

The mandate

Sets the deadline.

The ASP

Moves the invoice.

Atlas

Makes sure the data survives.

Why now

The mandate calendar is already booked.

Every wave is a new rule pack. Same engine.

2026

UAE FTA Phase 2

B2B e-invoicing live

Sep 2026

France

Reception mandatory · large enterprises issue

2027

Germany

Issuance mandatory for >€800k

2028

EU ViDA

Cross-border DRR framework

2029

HMRC e-invoicing rollout

Live rule pack UAE, France · In build Germany, Pillar Two, SAF-T, DAC7, ViDA, UK

Start with today’s mandate. The engine carries to the next one.

The product

See what will break before go-live.

Atlas turns your existing evidence into a live command center.

Evidence in

ERP extracts

Invoice samples

Master data

Mapping files

Documents

Workshops

Readiness out

Blockers

Owners

Decisions

Fixes

Approvals

Implementation handoff

The four questions

Four questions Atlas answers.

What will break?

Real records tested against the applicable rule pack.

Who owns the fix?

Every blocker gets an owner, action, and evidence.

What was decided?

Conflicts are surfaced. Decisions and approvals are preserved.

What hands off?

Scope, mappings, rules, test cases, actions, and open decisions.

Record → Rule → Owner → Evidence → Decision → Approval

The AI position

AI for coverage. Experts for judgment. Your data for proof.

Atlas uses AI agents to examine documents, records, requirements, and workshop evidence at scale.

Tax and implementation experts review material findings.

People approve every important decision.

Every finding traces to a record, a rule, and a registry response.

Nothing is invented.

The contrast

Not another readiness deck.

Traditional assessment

Atlas

Interviews and spreadsheets

Actual data and evidence

Static findings

Re-runnable command center

Recommendations

Owner-assigned actions

Decisions in meeting notes

Decisions and approvals preserved

Depends who shows up

Same engagement, any operator

Another implementation discovery

Working ASP and SI handoff

Proof on one field

The invoice passed validation. It still did not arrive.

The buyer TRN was correctly formatted, but one digit was wrong.

Atlas finding

Rule ID · CAN-R-03

Blocker

Buyer TRN fails verification

Source

Customer master

Owner

Master Data

Fix

Correct the registration record

Evidence

Source and verification result preserved

1,248

862

Readiness waterfall

Records that would fail on day one, cut by 31% after one Atlas re-run. 80% of leakage is in master data and tax logic.

One blocker. One owner. One fix.

Atlas applies the same investigation across every field, flow, system, and entity.

What implementation receives

A working implementation file. Not a findings deck.

Entity and transaction scope

Source systems and mappings

Data and tax-rule gaps

Test scenarios

Remediation owners and actions

Decisions and approvals

ASP and SI requirements

Start with your own data

Free account teardown.

Send a limited sample of invoice data, master data, or ERP extracts.

Receive

Selected blockers

Likely owners

Source of each issue

Brandable findings summary

The teardown identifies the problem. The full Atlas engagement defines the remediation, decisions, approvals, and implementation handoff.

Beyond e-invoicing

Every tax mandate creates the same engineering problem.

Scope → Map → Validate → Decide → Fix → Prove

Atlas uses one canonical model with swappable rule packs.

Start with e-invoicing.

Extend to tax-engine rollouts, ERP transformations, Pillar Two, SAF-T, DAC7, and future mandates.

E-invoicing

Tax-engine rollouts

ERP transformations

Pillar Two

SAF-T

DAC7

Built from both sides of the table

Experience developed at Amazon and Deloitte.

Our founders have built enterprise tax and compliance technology and led complex technology implementations.

Atlas was created so teams do not have to reconstruct requirements, decisions, owners, and approvals at go-live.

Amazon and Deloitte are former employers and do not endorse or sponsor OneSig Atlas.

For partners

Turn readiness into client and implementation revenue.

Atlas helps ASPs, ERP partners, systems integrators, and advisors turn readiness into client and implementation revenue.

You bring

The client relationship.

OneSig provides

The readiness engine.

You own

The work that follows.

Explore the partner model →