About us
We’re an early stage fintech company building a better way to pay. We’re a small team where engineers work closely with product, design, and business, and where clear thinking and clear communication matter as much as the code itself.
What you’ll work on
- Backend services in Go, from data model and schema design through deployment and operation.
- Systems that coordinate multi-step processes and need to stay correct and recover cleanly when individual steps fail.
- Design proposals and technical documents that help the team make good decisions.
- Reviewing others’ designs and code, and having your own reviewed in turn.
- Improving reliability over time, and making the case for addressing tech debt before it slows us down.
Who we’re looking for
- You’ve worked as a backend engineer in a professional setting and can talk in detail about services you built, how they held up in production, and what you learned from them.
- You’re strong in Go and relational database design, and you understand the trade-offs that come with distributed systems.
- You explain complex ideas simply, in writing and in conversation, to engineers and non-engineers alike.
- You ask for feedback on your work, take it seriously, and can point to times it changed your approach.
- You pick up unfamiliar tools and domains quickly, and you’re comfortable being productive before you know everything.
- You can take a goal and run with it independently, while keeping others informed without being asked.
Nice to have
- Business level Japanese (N2+)
- Experience taking a product from zero to production.
- Experience with workflow orchestration systems such as Temporal or AWS Step Functions.
- Experience in payments, banking, or other domains where correctness is a priority.
- Experience at an early-stage company, or a clear reason you want to be at one now.
- Familiarity with frontend or mobile development, enough to collaborate comfortably across the stack.
Our stack
Go, ConnectRPC/Protobuf, Temporal, PostgreSQL, AWS, Terraform
You don’t need experience with all of these. We’d love to talk to someone who has gone deep on a few and learns the rest quickly.
What it’s like here
- Direct access to decision makers. Good ideas get heard and acted on quickly.
- Real ownership of your work, with support from the team when you need it.
- A culture of open, honest feedback in both directions.
How to apply
Along with your resume, send a short written note about a technical problem you solved at work. Tell us what the constraints were, what you tried that didn’t work, and what you’d change today. We’d love to hear this in your own words, since how you explain your thinking matters to us as much as the problem itself.
About Jamm
Jamm enables online customers to make digital payments directly from their bank account. Their service is compatible with over 300 financial institutions, including major Japanese banks.
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