Emil Lundberg
Software Engineer at Yubico
Stockholm, Stockholm County, Sweden
Summary
🤩
RockstarEmil Lundberg is a pragmatic software engineer in Stockholm with 12 years of experience building robust back-end systems and improving developer tooling. Comfortable across Java, Rust and Python, he has contributed to high-profile open-source projects—implementing Ed25519 support and TPM attestation in Yubico’s WebAuthn server, refining libgit2 Rust bindings, and hardening Syncthing’s API and auth flows. He blends a physicist’s attention to correctness with a tinkerer’s curiosity, often driving refactors, test automation, and performance benchmarks (notably in the time-rs crate). Emil’s work shows a focus on security-sensitive features and core library internals rather than surface polish, making him effective at solving subtle correctness and interoperability challenges.
12 years of coding experience
Stackoverflow
7,308reputation
2.8mreached
75answers
20questions
javascript
top-5%
Github Skills (57)
git10
benchmark10
libgit210
docker10
test-driven-design10
github-ci10
python10
quickcheck10
api-design10
testing10
underscorejs10
authentication10
user-authentication10
benchmarking10
dockers10
Programming languages (28)
Github contributions (5)
Yubico/java-webauthn-server
Aug 2017 - Jan 2023
Server-side Web Authentication library for Java https://www.w3.org/TR/webauthn/#rp-operations
Role in this project:
Back-end Developer
Back-end DeveloperContributions:98 releases, 23 reviews, 2286 commits in 5 years 5 months
Contributions summary:Emil primarily worked on core functionality of the Java WebAuthn server library, including the creation of test data, and the implementation and testing of new features. They were responsible for adding support for the Ed25519 signature algorithm, and integrating it with existing COSE and key import functionality. Their work also included adding policy tree validation for TPM attestation, along with general improvements to the core library and code quality.
authorizationpasskeywebauthnweb-authenticationfido-u2f
Yubico/yubikey-manager
Sep 2017 - Sep 2021
Python library and command line tool for configuring any YubiKey over all USB interfaces.
Role in this project:Back-end Developer & Test Automation Engineer
Back-end Developer & Test Automation EngineerContributions:1 release, 2 reviews, 617 commits in 4 years
Contributions summary:Emil primarily contributed to the PIV (Personal Identity Verification) and OATH (Open Authentication) functionalities of the YubiKey Manager. Their work involved breaking out integration tests for RSA2048 key generation and modifying code to prevent RSA key generation on affected YubiKeys. The user also added functionality related to FIDO 2, including FIPS support. Furthermore, they made changes to OATH to improve credential listing and code generation, indicating a focus on improving the user experience and security.
command-line-toolpython-librarypythonyubikeypiv
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