🆕
Modern .NET 9 from scratch
Unlike legacy Java-based signing tools, it was written from day one on an async/await architecture — a UI that never freezes, high throughput, easy maintenance.
✍️ Two Separate Electronic Signature Products ELPO e-Signature Solutions
ELPO e-Signature Solutions
Two Separate Products, Two Different Needs.
ELPO's two independent products in electronic signing. İmzacı — a modern desktop application for anyone who needs to sign documents. SignaturePro — a .NET library (SDK) for developers who want to embed electronic signing into their own software.
Separate products, separate users — both built by ELPO; supporting CAdES, XAdES, PAdES, ASiC standards with smart cards, USB tokens, mobile signing and timestamping. ETSI/eIDAS and Turkish Law No. 5070 compliant.
contract.pdf
PAdES B-LTA · long-term archive
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Signer · Qualified Certificate
Smart card · SHA-256 · RSA 2048
⏱️
Timestamp · KamuSM
RFC 3161 · failover active
✓ Chain & Revocation Check
OCSP + CRL · certificate trusted
🧭 Which One Fits You?
Two Separate Products — Which One Fits You?
İmzacı and SignaturePro are two independent products. Do you want to sign documents, or add signing capability to your own software? Choose the one that fits your need.
End User · Application
İmzacı
"I have a document and I need to sign it." Install it on your computer; sign PDF, XML, Word or any file with a smart card/USB token in a few clicks, verify it, and prepare e-Yazışma packages.
Desktop Windows · Linux · macOS Smart Card
Explore İmzacı
Developer · SDK / NuGet
SignaturePro
"I want to add electronic signing to my own application." A modular .NET library — pull only the package you need from NuGet, sign in a few lines of code, verify, and integrate mobile signing/HSM.
.NET 9 39 NuGet packages Mobile Signature · HSM
Explore SignaturePro
Desktop Signing Application İmzacı — Next-Generation Electronic Signature
Forget the old, slow, freezing signing tools. İmzacı is built from the ground up on .NET 9 and a modern UI stack, running natively on all three operating systems and detecting your smart card instantly. Drag in your document, insert your card, sign.
3
Operating Systems
4
Signature Standards
CLI
+ GUI
LTA
Archive Level
Supported Signature Profiles
CAdES BES · EPES · T · C · X · XL · A
CMS / PKCS#7 — binary document and data signatures
XAdES BES · T · C · X · XL · A
Structured signatures for XML documents and e-invoices
PAdES B-B · B-T · B-LT · B-LTA
Embedded inside the PDF, visible/invisible signatures
ASiC ASiC-S · ASiC-E
Packs the signature and documents into a single container
What legacy tools simply can't do
🖥️
Native Cross-Platform
Runs natively on Windows, Linux and macOS from a single code base. .NET 9 + Avalonia — no Java virtual machine required, lightweight to install.
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Event-Driven Smart Card
Detects a card the instant it is inserted or removed. Uses noticeably less CPU than legacy tools that constantly poll, and discovers the PKCS#11 library automatically.
⏱️
Multiple Timestamps + Failover
Automatic switchover and caching across KamuSM, TSE and RFC 3161 providers. If one TSA doesn't respond, signing doesn't stall — it falls through to the next.
📑
The Full Range of ETSI Profiles
CAdES (BES→A), XAdES (BES/T/C/X/XL/A), PAdES (B-B→B-LTA) and ASiC-S/E. All the way up to long-term archive (LTA) in a single application.
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e-Yazışma & Batch Signing
Official e-Yazışma v1.3 / v2.0 packages, KamuSM root certificate integration and folder-based batch signing — ready for enterprise document workflows.
⌨️
CLI + Scheduling (DevOps)
More than a UI; sign, verify and batch-process from the command line. With cron-like scheduling you can set up automated overnight signing pipelines.
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Plugin Architecture
Custom signer/verifier plugins can be loaded. An extensible design so an organization can add its own business rules without touching the core.
🛡️
Enterprise Network & Proxy
OCSP, CRL, TSA and repository access all run through the proxy. Works seamlessly behind a corporate firewall; plus certificate revocation checks via CRL/OCSP.
Developer SDK · NuGet SignaturePro — Signing Power for Your Software
Building electronic signing from scratch takes months; with SignaturePro it takes a few lines. A production-ready, modular .NET library: add only the signature standard, mobile operator or TSA provider you need as a separate package.
Program.cs
# A single package is enough for PDF signing
dotnet add package SignatureProNet.PAdES
var signer = new PAdESService();
var signature = await signer.SignAsync(
pdf, certificate, level: SignatureLevel.BLTA);
// verify the signature
var result = await signer.VerifyAsync(signature);🧩
Truly Modular — 39 Packages
Install only what you need. Signing PDFs only? SignatureProNet.PAdES is enough. No bloat, minimal dependencies.
🌍
Global Standards Support
European ETSI/eIDAS (CAdES/XAdES/PAdES/ASiC) in production; US FIPS, China GM/T, Russia GOST, Brazil ICP and India eSign are on the roadmap. Full Turkish Law 5070 compliance.
📱
Mobile Signature — 3 Operators
Turkcell, Vodafone and Türk Telekom mobile signature, each as a separate package. Start with a phone number, let the user approve, complete the signature.
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Smart Card, USB Token & HSM
Smart card/USB token via PKCS#11 and Windows CNG. Modular integration for cloud HSM (AWS, Azure, Google) and network HSM (enterprise) providers.
🕓
11+ Timestamp Providers
KamuSM, GlobalSign, DigiCert, Sectigo, Entrust, FreeTSA and more. Each TSA is a separate package — you only reference the one you use.
✅
Full Certificate Validation
RFC 5280 chain validation, CRL, OCSP, Delta CRL and offline validation. Bank/government-grade trust chain verification.
🔐 Signing Hardware & Services
From smart cards to cloud HSM — signs anywhere
SignaturePro doesn't care where the signing key lives: a USB token in your pocket, an enterprise HSM, or the cloud. Each provider is a separate, independent package.
💳
Smart Card & USB Token
Windows CNG + PKCS#11 — no third-party middleware required
AKİSSafeNet / eTokenGemalto / ThalesOberthur / IDEMIAAladdin / EutronFeitian / RockeyYubiKeyNitrokeySafeSignCryptoPro / RuToken
🏛️
Network HSM
High-volume signing with enterprise hardware security modules
Thales LunaUtimaco SecurityServerEntrust nShield (nCipher)
☁️
Cloud HSM
Keys in the cloud, backed by hardware assurance
AWS CloudHSM / KMSAzure Key Vault HSMGoogle Cloud KMS
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Mobile Signature
Qualified signing via the phone SIM — each operator a separate package
TurkcellVodafoneTürk Telekom
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Timestamping (TSA)
RFC 3161 — each provider a separate package, automatic failover
KamuSMGlobalSignDigiCertSectigoEntrustFreeTSA
Brand names belong to their respective owners; SignaturePro interoperates with these devices/services through PKCS#11, CNG and the relevant APIs.
Performance
Typical signing/verification times measured on reference hardware.
~12 ms
CAdES signing (1 MB)
~18 ms
XAdES signing (1 MB)
~145 ms
PAdES signing (10 MB PDF)
~8 ms
CAdES verification
🛡️ Foundation of Trust
Full Standards Compliance
Both products — İmzacı and SignaturePro — are independently compliant with national and international electronic signature standards. Your signatures stay valid today and years from now.
ETSI EN 319 122/132/142/162
CAdES · XAdES · PAdES · ASiC European standards
eIDAS (EU) 910/2014
European electronic identification and trust services
Turkish Law No. 5070
Compliance with Turkey's electronic signature legislation
TÜBİTAK compliant
Aligned with national crypto/signature reference algorithms
RFC 3161 / 5652 / 6960
Timestamp · CMS · OCSP protocols
KamuSM integration
Root certificate and official TSA connectivity
⚡ Why ELPO?
6 things that set ELPO apart in e-Signature
A modern, fast, fully standards-compliant alternative to the heavyweight signing tools used for years — and one you can get as both an application and an SDK from a single source.
🇹🇷
Local engineering, local support
A product built with ELPO engineering that understands local needs like KamuSM/e-Yazışma and provides on-the-ground support.
🤝
Two products, one vendor
İmzacı for the end user, the SignaturePro library for the developer — two separate products, but a single point of contact, one support line, one invoice.
📚
Full standards compliance
ETSI profiles from BES all the way to long-term archive (LTA/A) — your signatures stay verifiable years down the line.
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Modular & extensible
39 independent packages on the SDK side, a plugin architecture on the application side. Scale as needed, carry no dead weight.
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Integrated into the ELPO ecosystem
Shares the same signing infrastructure with ELPO products like e-Belge, SmartERP and Cortex — end-to-end signing across enterprise processes.
Take Your Signature Digital
Whether you sign your documents with İmzacı or embed the SignaturePro SDK into your software — the ELPO team is with you from setup to integration.