Node.js Engineering at Tessian

Our Node.js team are building a scalable infrastructure for processing email traffic in real-time (and you can read about our building an email load tester in Node.js here). You’ll be an experienced software engineer with a strong interest in developing backend services in Node.js. Our stack includes core Node.js, Docker, AWS/Azure, and Postgres, amongst others and you’ll be helping to build a new generation of dependable AI-based enterprise security.

Unlike most Node.js roles we’re using this technology to execute some pretty low-level concepts and we’re drilling down to fundamentals. This isn’t an Express app or a full-stack web role; we’re building a core, high-performance backend to support Tessian’s cybersecurity platform. You’ll make a big impact in a small team, with opportunities to drive our future technology, mentor other developers and solve business-critical issues.

You’ll be a great thinker and have the ability to plan, question, suggest and explain – skills we value as highly as your ability to write solid, dependable code. As part of our team, you’ll be collaborating with our Data Scientists who are building new machine learning threat models, architecting our application to scale with our growing client base, diagnosing critical issues and contributing to planning and architecture discussions.

We believe in regular and continuous development and seek to create opportunities for all team members. We have regular cross-discipline tech talks and we encourage multi-disciplinary development. Dealing with massive datasets at scale requires ingenuity and strong analytical skills, and we build quickly, following both agile and continuous delivery paradigms. You’ll have a degree of autonomy to work on your various projects, and be a part of our regular round tables to bounce ideas around. We believe in continuous career development and will look to create opportunities for you to evolve both personally and professionally.

We’d love to meet someone who

-Is a backend software engineer with 5+ years of professional experience – Ideally with extensive knowledge of Node.js, and demonstrable experience of building multi-threaded/asynchronous engineering technology
-Has great knowledge of Node.js: knowing promises from callbacks and able to configure a package.json whilst asleep
-Experience with core Node.js (crypto, fs, net) is even better, and it’s useful to have knowledge of the basics of Docker and why containerisation is useful
-Knows how to code on non-trivial software projects
-Understands how open-source projects work (if you have existing projects or contributions that’s perfect- please do send us links in your cover letter!)
-Is able to apply software best-practices with regards to application security, including issue tracking, testing and code reviews
-Loves writing server-side software, and thinks it’d be great to work with the benefits of a highly efficient platform
-Is interested in email technologies, protocols, problems and threats
-Is willing to learn, build and contribute

Why we think you’ll love it here

-You’ll work alongside amazing, high-performing colleagues with a real dedication to best practices and programming excellence
-You’ll be working on non-trivial projects, at the cutting edge of the current usage of Node.js
-We offer a competitive salary which will depend on your specific experience, with annual benefit and salary reviews
-Equity options are offered with every role
-Everyone gets 25 days of paid annual leave (33 days including bank holidays)
-Company contributions are made towards your pension
-You’ll get to choose your own kit: laptop & OS
-Flexible morning-start times on the Engineering team
-We have a communal company lunch twice a month, and regular team socials and activities
-There are plenty of office snacks including fruit, nuts, bread, and cereals, and amazing coffee
-We offer a cycle to work scheme, eyecare vouchers and childcare vouchers
-Weekly yoga sessions in the office
-If you’re coming from abroad, we’ll provide relocation assistance including flights, accommodation in an AirBnB for 3 weeks, and salary payments to an international bank. Over 25% of the company is international and we’re always as supportive as we can be in helping people make the move


Tessian is a machine intelligent email security platform to automatically prevent cybersecurity threats like spear phishing, misaddressed emails, unauthorized emails (data loss) and non-compliance.

We’re a team of mathematicians, data scientists & engineers building breakthrough machine learning and natural language technology to analyse, understand & protect enterprise email networks.

We’ve just announced our raise of £9m ($13m) in a Series A round led by Balderton Capital and Accel Partners. Last year our business grew 400% and our team expanded from 13 to 50 people; we have ambitious growth plans for the next year, spanning all areas including our product offerings and our sales & marketing divisions. We’re excited about where this next phase of our growth will take us – we hope you are too, so we encourage you to apply today to be part of the next leg of the Tessian journey.

We’re backed by world-leading venture capital funds who’ve invested in companies like Facebook, Slack, Dropbox, Improbable & Transferwise & we’ve been named on the prestigious Forbes 30 Under 30 list, crowned the “Best Security Startup” by WIRED magazine, and awarded “Best Innovation in Data Protection & Privacy” by CogX.

Our team

You can check out some photos of our team on our Instagram, look at our company page. You can also find us on Glassdoor.

Equality & diversity

Tessian is an equal opportunity employer, committed to equality and diversity amongst both our employees and prospective applicants. You can read our equality and diversity statement here. We’re also a corporate member of the WISE Campaign for gender equality in STEM, with a staff member on the WISE Young Women’s Board.

How to apply

Please click on the ‘Apply for this Job’ button to be taken to the application form which will collect all the necessary information.

Want to make your application stand out? We value well thought-out, Tessian-specific cover letters; you can write yours in the ‘Additional Information’ section of the application form.

Important notices

Please note that we do not accept applications or résumés from recruiters.

By submitting your application to Tessian, you consent to Tessian contacting you about future job opportunities, that may be of interest, for up to 2 years in accordance with our Privacy Policy

Please note, that any job offers will be subject to the candidate passing background screening checks.

Tagged as: backend, engineering, Node.js